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• Creating dynamic plots

  - by geoff92

  I'm completely new to web programming but I do have a programming background. I'd like to create a site that allows users to visit, enter some specifications into a form, submit the form, and then receive a graph. I have a few questions about this, only because I'm pretty ignorant: Is there a good framework I should start in? I know a lot of java, I'm okay with python, and I learned Ruby in the past. I figure I might use ruby on rails only because I hear of it so often and I think I've also heard it's easy. If anyone has some other recommendation, please suggest. The user will be entering data into a form. I'm guessing the request they'll be making should be one of a GET request, right? Because I don't intend for any of the data they're entering to modify my server (in fact, I don't intend on having a database). The data the user inputs will be used to perform calculations involving lots of matrices. I've written this functionality in python. If I use ruby on rails, should it be instead written in Ruby? Somewhere I've heard that you can either place the load of the work on your server or on the client's computer. Since the code performs heavy math, which option is preferable? How do I alter the setup to either make the client do the work or my server? Should I be using a "cgi-bin"? In the code that I have now, I use matplotlib, a python library, and then "show" the plot in order to see the graph. I specify the x and y limits, but I am able to "drag" the graph in order to see more data within the plot window. Ultimately, I want a graph to be shown on my site with the drag functionality. Is this possible? What if the client drags the graph so far, more computations must be made? Thanks!

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• How to learn to program [on hold]

  - by user94914

  I went to a community college and got a degree in computer science, but I found out I only learn very little about programming. As a result I landed byself a office assistant work (for a year now), I want to study on my own and apply for some internship / very entry level development job. I am wondering how should a person learn to program now? I feel that I might not doing it correctly, I understand everyone has a different approach, but I am really clueless on what to do, as it seems I am 5-10 years away. 1) Read the old college programming textbook cover to cover, learn every single concepts, do all the practice problems and master them (1-2 times until error free). Currently reading this java book 2) Work on any project, keep on googling and reading tutorials (including the books on that specific language). I have been doing 1, but the progress is really slow, about 2-5 pages / hour, over a 1000+ page book, I felt really discouraged. I have a few of them to go through (data struction, analyis algorthim, computer theory, operating system.) I wonder is this the right method to do? I know it is going to take time, but I am hoping to get some advice from current programmers.

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• How should a non-IT manager secure the long-term maintenance and development of essential legacy software?

  - by user105977

  I've been hunting for a place to ask this question for quite a while; maybe this is the place, although I'm afraid it's not the kind of "question with an answer" this site would prefer. We are a small, very specialized, benefits administration firm with an extremely useful, robust collection of software, some written in COBOL but most in BASIC. Two full-time consultants have ably maintained and improved this system over more than 30 years. Needless to say they will soon retire. (One of them has been desperate to retire for several years but is loyal to a fault and so hangs on despite her husband's insistence that golf should take priority.) We started down the path of converting to a system developed by one of only three firms in the country that offer the type of software we use. We now feel that although this this firm is theoretically capable of completing the conversion process, they don't have the resources to do so timely, and we have come to believe that they will be unable to offer the kind of service we need to run our business. (There's nothing like being able to set one's own priorities and having the authority to allocate one's resources as one sees fit.) Hardware is not a problem--we are able to emulate very effectively on modern servers. If COBOL and BASIC were modern languages, we'd be willing to take the risk that we could find replacements for our current consultants going forward. It seems like there ought to be a business model for an IT support firm that concentrates on legacy platforms like this and provides the programming and software development talent to support a system like ours, removing from our backs the risks of finding the right programming talent and the job of convincing younger programmers that they can have a productive, rewarding career, in part in an old, non-sexy language like BASIC. Where do I find such firms?

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• What is the fastest way for me to become a full stack developer? [on hold]

  - by user136368

  I run a small webdesign firm. I have an overview of HTML, CSS, JS, PHP(laravel), MySQL. I did a few courses on code academy. I wanted to build a web app in the company. I find that I am severely crippled by the lack of programming expertise. I want to become a full stack developer who can build a prototype on his own. I cannot spend 5-10k USD on the boot camp courses. Can someone suggest structured courses which can help me become a full stack developers? I found the following websites but I donot know if they can help me become one. My goal: Be able to make a working prototype of the ideas I come up with.(This is my primary goal. I do not want to be the lead developer. I just want to be able to make a prototype.) Several questions I have in mind: Will it be fine if I stick to PHP(laravel)? Should I be using ROR? I have come across a few online resources: Codeacademy, codeschool,teamtreehouse,and theodinproject. These are within my affordability range. I can commit to a 2-3 months intensively to learn programming. What do you suggest I do?

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• Psychology researcher wants to learn new language

  - by user273347

  I'm currently considering R, matlab, or python, but I'm open to other options. Could you help me pick the best language for my needs? Here are the criteria I have in mind (not in order): Simple to learn. I don't really have a lot of free time, so I'm looking for something that isn't extremely complicated and/or difficult to pick up. I know some C, FWIW. Good for statistics/psychometrics. I do a ton of statistics and psychometrics analysis. A lot of it is basic stuff that I can do with SPSS, but I'd like to play around with the more advanced stuff too (bootstrapping, genetic programming, data mining, neural nets, modeling, etc). I'm looking for a language/environment that can help me run my simpler analyses faster and give me more options than a canned stat package like SPSS. If it can even make tables for me, then it'll be perfect. I also do a fair bit of experimental psychology. I use a canned experiment "programming" software (SuperLab) to make most of my experiments, but I want to be able to program executable programs that I can run on any computer and that can compile the data from the experiments in a spreadsheet. I know python has psychopy and pyepl and matlab has psychtoolbox, but I don't know which one is best. If R had something like this, I'd probably be sold on R already. I'm looking for something regularly used in academe and industry. Everybody else here (including myself, so far) uses canned stat and experiment programming software. One of the reasons I'm trying to learn a programming language is so that I can keep up when I move to another lab. Looking forward to your comments and suggestions. Thank you all for your kind and informative replies. I appreciate it. It's still a tough choice because of so many strong arguments for each language. Python - Thinking about it, I've forgotten so much about C already (I don't even remember what to do with an array) that it might be better for me to start from scratch with a simple program that does what it's supposed to do. It looks like it can do most of the things I'll need it to do, though not as cleanly as R and MATLAB. R - I'm really liking what I'm reading about R. The packages are perfect for my statistical work now. Given the purpose of R, I don't think it's suited to building psychological experiments though. To clarify, what I mean is making a program that presents visual and auditory stimuli to my specifications (hundreds of them in a preset and/or randomized sequence) and records the response data gathered from participants. MATLAB - It's awesome that cognitive and neuro folk are recommending MATLAB, because I'm preparing for the big leap from social and personality psychology to cognitive neuro. The problem is the Uni where I work doesn't have MATLAB licenses (and 3750 GBP for a compiler license is not an option for me haha). Octave looks like a good alternative. PsychToolbox is compatible with Octave, thankfully. SQL - Thanks for the tip. I'll explore that option, too. Python will be the least backbreaking and most useful in the short term. R is well suited to my current work. MATLAB is well suited to my prospective work. It's a tough call, but I think I am now equipped to make a more well-informed decision about where to go next. Thanks again!

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• E-Business Suite Technology Sessions at OpenWorld 2012

  - by Max Arderius

  Oracle OpenWorld 2012 is almost here! We're looking forward to updating you on our products, strategy, and roadmaps. This year, the E-Business Suite Applications Technology Group (ATG) will participate in 25 speaker sessions, two Meet the Experts round-table discussions, five demoground booths and seven Special Interest Group meetings as guest speakers. We hope to see you at our sessions.  Please join us to hear the latest news and connect with senior ATG development staff. Here's a downloadable listing of all Applications Technology Group-related sessions with times and locations: FOCUS ON Oracle E-Business Suite - Applications Tools and Technology (PDF) General Sessions GEN8474 - Oracle E-Business Suite - Strategy, Update, and RoadmapCliff Godwin, SVP, Oracle Monday, Oct 1, 12:15 PM - 1:15 PM - Moscone West 2002/2004 In this session, hear Oracle E-Business Suite General Manager Cliff Godwin deliver an update on the Oracle E-Business Suite product line. This session covers the value delivered by the current release of Oracle E-Business Suite, the momentum, and how Oracle E-Business Suite applications integrate into Oracle’s overall applications strategy. You’ll come away with an understanding of the value Oracle E-Business Suite applications deliver now and will deliver in the future. GEN9173 - Optimize and Extend Oracle Applications - The Path to Oracle Fusion ApplicationsNadia Bendjedou, Oracle; Corre Curtice, Bhavish Madurai (CSC) Tuesday, Oct 2, 10:15 AM - 11:15 AM - Moscone West 3002/3004 One of the main objectives of this session is to help organizations build their IT roadmap for the next five years and be aligned with the Oracle Applications strategy in general and the Oracle Fusion Applications strategy in particular. Come hear about some of the common sense, practical steps you can take to optimize the performance of your Oracle Applications today and prepare your path to Oracle Fusion Applications for when your organization is ready to embrace them. Each step you take in adopting Oracle Fusion technology gets you partway to Oracle Fusion Applications. Conference Sessions CON9024 - Oracle E-Business Suite Technology: Latest Features and Roadmap Lisa Parekh, Oracle Monday, Oct 1, 10:45 AM - 11:45 AM - Moscone West 2016 This Oracle development session provides a comprehensive overview of Oracle’s product strategy for Oracle E-Business Suite technology, the capabilities and associated business benefits of recent releases, and a review of capabilities on the product roadmap. This is the cornerstone session for the Oracle E-Business Suite technology stack. Come hear about the latest new usability enhancements of the user interface; systems administration and configuration management tools; security-related updates; and tools and options for extending, customizing, and integrating Oracle E-Business Suite with other applications. CON9021 - Oracle E-Business Suite Future Directions: Deployment and System AdministrationMax Arderius, Oracle Monday, Oct 1, 3:15 PM - 4:15 PM - Moscone West 2016  What’s coming in the next major version of Oracle E-Business Suite 12? This Oracle Development session covers the latest technology stack, including the use of Oracle WebLogic Server (Oracle Fusion Middleware 11g) and Oracle Database 11g Release 2 (11.2). Topics include an architectural overview of the latest updates, installation and upgrade options, new configuration options, and new tools for hot cloning and automated “lights-out” cloning. Come learn how online patching (based on the Oracle Database 11g Release 2 Edition-Based Redefinition feature) will reduce your database patching downtimes to however long it takes to bounce your database server. CON9017 - Desktop Integration in Oracle E-Business Suite 12.1 Padmaprabodh Ambale, Gustavo Jimenez, Oracle Monday, Oct 1, 4:45 PM - 5:45 PM - Moscone West 2016 This presentation covers the latest functional enhancements in Oracle Web Applications Desktop Integrator and Oracle Report Manager, enhanced Microsoft Office support, and greater support for building custom desktop integration solutions. The session also presents tips and tricks for upgrading from Oracle Applications Desktop Integrator to Oracle Web Applications Desktop Integrator and Oracle Report Manager. CON9023 - Oracle E-Business Suite Technology Certification Primer and Roadmap Steven Chan, Oracle Tuesday, Oct 2, 10:15 AM - 11:15 AM - Moscone West 2016  Is your Oracle E-Business Suite technology stack up to date? Are you taking advantage of all the latest options and capabilities? This Oracle development session summarizes the latest certifications and roadmap for the Oracle E-Business Suite technology stack, including elements such as database releases and options, Java, Oracle Forms, Oracle Containers for J2EE, desktop operating systems, browsers, JRE releases, development and Web authoring tools, user authentication and management, business intelligence, Oracle Application Management Packs, security options, clouds, Oracle VM, and virtualization. The session also covers the most commonly asked questions about tech stack component support dates and upgrade implications. CON9028 - Minimizing Oracle E-Business Suite Maintenance DowntimesSantiago Bastidas, Elke Phelps, Oracle Tuesday, Oct 2, 11:45 AM - 12:45 PM - Moscone West 2016 This Oracle development session features a survey of the best techniques sysadmins can use to minimize patching downtimes. It starts with an architectural-level review of Oracle E-Business Suite fundamentals and then moves to a practical view of the various tools and approaches for downtimes. Topics include patching shortcuts, merging patches, distributing worker processes across multiple servers, running ADPatch in noninteractive mode, staged APPL_TOPs, shared file systems, deferring systemwide database tasks, avoiding resource bottlenecks, and more. An added bonus: hear about the upcoming Oracle E-Business Suite 12 online patching capabilities based on the groundbreaking Oracle Database 11g Release 2 Edition-Based Redefinition feature. CON9116 - Extending the Use of Oracle E-Business Suite with the Oracle Endeca PlatformOsama Elkady, Muhannad Obeidat, Oracle Tuesday, Oct 2, 11:45 AM - 12:45 PM - Moscone West 2018 The Oracle Endeca platform includes a leading unstructured data correlation and analytics engine, together with a best-in class catalog search and guided navigation solution, to improve the productivity of all types of users in your enterprise. This development session focuses on the details behind the Oracle Endeca platform’s integration into Oracle E-Business Suite. It demonstrates how easily you can extend the use of the Oracle Endeca platform into other areas of Oracle E-Business Suite and how you can bring in your own data and build new Oracle Endeca applications for Oracle E-Business Suite. CON9005 - Oracle E-Business Suite Integration Best PracticesVeshaal Singh, Oracle, Jeffrey Hand, Zebra Technologies Tuesday, Oct 2, 1:15 PM - 2:15 PM - Moscone West 2018 Oracle is investing across applications and technologies to make the application integration experience easier for customers. Today Oracle has certified Oracle E-Business Suite on Oracle Fusion Middleware 11g and provides a comprehensive set of integration technologies. Learn about Oracle’s integration offering across data- and process-centric integrations. These technologies can be used to address various application integration challenges and styles. In this session, you will get an understanding of how, when, and where you can leverage Oracle’s integration technologies to connect end-to-end business processes across your enterprise, including your Oracle Applications portfolio.  CON9026 - Latest Oracle E-Business Suite 12.1 User Interface and Usability EnhancementsPadmaprabodh Ambale, Oracle Tuesday, Oct 2, 1:15 PM - 2:15 PM - Moscone West 2016 This Oracle development session details the latest UI enhancements to Oracle Application Framework in Oracle E-Business Suite 12.1. Developers will get a detailed look at new features to enhance usability, offer more capabilities for personalization and extensions, and support the development and use of dashboards and Web services. Topics include new rich UI capabilities such as new home page features, Navigator and Favorites pull-down menus, REST interface, embedded widgets for analytics content, Oracle Application Development Framework (Oracle ADF) task flows, third-party widgets, a look-ahead list of values, inline attachments, pop-ups, personalization and extensibility enhancements, business layer extensions, Oracle ADF integration, and mobile devices. CON8805 - Planning Your Oracle E-Business Suite Upgrade from 11i to Release 12.1 and BeyondAnne Carlson, Oracle Tuesday, Oct 2, 5:00 PM - 6:00 PM - Moscone West 3002/3004 Attend this session to hear the latest Oracle E-Business Suite 12.1 upgrade planning tips from Oracle’s support, consulting, development, and IT organizations. You’ll get specific cross-product advice on how to understand the factors that affect your project’s duration, decide on your project’s scope, develop a robust testing strategy, leverage Oracle Support resources, and more. In a nutshell, this session tells you things you need to know before embarking upon your Release 12.1 upgrade project. CON9053 - Advanced Management of Oracle E-Business Suite with Oracle Enterprise ManagerAngelo Rosado, Oracle Tuesday, Oct 2, 5:00 PM - 6:00 PM - Moscone West 2016 The task of managing and monitoring Oracle E-Business Suite environments can be very challenging. Oracle Enterprise Manager is the only product on the market that is designed to monitor and manage all the different technologies that constitute Oracle E-Business Suite applications, including end user, midtier, configuration, host, and database management—to name just a few. Customers that have implemented Oracle Enterprise Manager have experienced dramatic improvements in system visibility and diagnostic capability as well as administrator productivity. The purpose of this session is to highlight the key features and benefits of Oracle Enterprise Manager and Oracle Application Management Suite for Oracle E-Business Suite. CON8809 - Oracle E-Business Suite 12.1 Upgrade Best Practices: Technical InsightIsam Alyousfi, Udayan Parvate, Oracle Wednesday, Oct 3, 10:15 AM - 11:15 AM - Moscone West 3011 This session is ideal for organizations thinking about upgrading to Oracle E-Business Suite 12.1. It covers the fundamentals of upgrading to Release 12.1, including the technology stack components and supported upgrade paths. Hear from Oracle Development about the set of best practices for patching in general and executing the Release 12.1 technical upgrade, with special considerations for minimizing your downtime. Also get to know about relatively recent upgrade resources. CON9032 - Upgrading Your Customizations of Oracle E-Business Suite 12.1Sara Woodhull, Oracle Wednesday, Oct 3, 10:15 AM - 11:15 AM - Moscone West 2016 Have you personalized Oracle Forms or Oracle Application Framework screens in Oracle E-Business Suite? Have you used mod_plsql in Release 11i? Have you extended or customized your Release 11i environment with other tools? The technical options for upgrading these customizations as part of your Oracle E-Business Suite Release 12.1 upgrade can be bewildering. Come to this Oracle development session to learn about selecting the best upgrade approach for your existing customizations. The session will help you understand customization scenarios and use cases, tools, and technologies to ensure that your Oracle E-Business Suite Release 12.1 environment fits your users’ needs closely and that any future customizations will be easy to upgrade. CON9259 - Oracle E-Business Suite Internationalization and Multilingual FeaturesMaher Al-Nubani, Oracle Wednesday, Oct 3, 10:15 AM - 11:15 AM - Moscone West 2018 Oracle E-Business Suite supports more countries, languages, and regions than ever. Come to this Oracle development session to get an overview of internationalization features and capabilities and see new Release 12 features such as calendar support for Hijra and Thai, new group separators, lightweight multilingual support (MLS) setup, new character sets such as AL32UTF, newly supported languages, Mac certifications, Oracle iSetup support for moving MLS setups, new file export options for Unicode, new MLS number spelling options, and more. CON7188 - Mobile Apps for Oracle E-Business Suite with Oracle ADF Mobile and Oracle SOA SuiteSrikant Subramaniam, Joe Huang, Veshaal Singh, Oracle Wednesday, Oct 3, 10:15 AM - 11:15 AM - Moscone West 3001 Follow your mobile customers, employees, and partners with Oracle Fusion Middleware. See how native iPhone and iPad applications can easily be built for Oracle E-Business Suite with the new Oracle ADF Mobile and Oracle SOA Suite. Using Oracle ADF Mobile, developers can quickly develop native applications for Apple iOS and other mobile platforms. The Oracle SOA Suite/Oracle ADF Mobile combination can execute business transactions on Oracle E-Business Suite. This session includes a demo in which a mobile user approves a business transaction in Oracle E-Business Suite and a demo of the tools used to build a native on-device solution. These concepts for mobile applications also apply to other Oracle applications.CON9029 - Oracle E-Business Suite Directions: Slashing Downtimes with Online PatchingKevin Hudson, Oracle Wednesday, Oct 3, 11:45 AM - 12:45 PM - Moscone West 2016 Oracle E-Business Suite will soon include online patching (based on the Oracle Database 11g Release 2 Edition-Based Redefinition feature), which will reduce your database patching downtimes to however long it takes to bounce your database server. This Oracle development session details how online patching works, with special attention to what’s happening at a database object level when database patches are applied to an Oracle E-Business Suite environment that’s still running. Come learn about the operational and system management implications for minimizing maintenance downtimes when applying database patches with this new technology and the related impact on customizations you might have built on top of Oracle E-Business Suite. CON8806 - Upgrading to Oracle E-Business Suite 12.1: Technical and Functional PanelAndrew Katz, Komori America Corporation; Sandra Vucinic, VLAD Group, Inc. ;Srini Chavali, Cummins Inc.; Amrita Mehrok, Nadia Bendjedou, Anne Carlson Oracle Wednesday, Oct 3, 1:15 PM - 2:15 PM - Moscone West 2018 In this panel discussion, Oracle experts, customers, and partners share their experiences in upgrading to the latest release of Oracle E-Business Suite, Release 12.1. The panelists cover aspects of a typical Release 12 upgrade, technical (upgrading the technical infrastructure) as well as functional (upgrading to the new financial infrastructure). Hear directly from the experts who either develop the product or support, implement, or upgrade it, and find out how to apply their lessons learned to your organization. CON9027 - Personalize and Extend Oracle E-Business Suite Applications with Rich MashupsGustavo Jimenez, Padmaprabodh Ambale, Oracle Wednesday, Oct 3, 1:15 PM - 2:15 PM - Moscone West 2016 This session covers the use of several Oracle Fusion Middleware technologies to personalize and extend your existing Oracle E-Business Suite applications. The Oracle Fusion Middleware technologies covered include Oracle Application Development Framework (Oracle ADF), Oracle WebCenter, Oracle Endeca applications, and Oracle Business Intelligence Enterprise Edition with Oracle E-Business Suite Oracle Application Framework applications. CON9036 - Advanced Oracle E-Business Suite Architectures: Maximum Availability, Security, and MoreElke Phelps, Oracle Wednesday, Oct 3, 3:30 PM - 4:30 PM - Moscone West 2016 This session includes architecture diagrams and configuration instructions for building a maximum availability architecture (MAA) that will help you design a disaster recovery solution that fits the needs of your business. Database and application high-availability features it describes include Oracle Data Guard, Oracle Real Application Clusters (Oracle RAC), Oracle Active Data Guard, load-balancing Web and forms services, parallel concurrent processing, and the use of Oracle Exalogic and Oracle Exadata to provide a highly available environment. The session also covers the latest updates to systems management tools, AutoConfig, cloud computing, virtualization, and Oracle WebLogic Server and provides sneak previews of upcoming functionality. CON9047 - Efficiently Scaling Oracle E-Business Suite on Oracle Exadata and Oracle ExalogicIsam Alyousfi, Nishit Rao, Oracle Wednesday, Oct 3, 5:00 PM - 6:00 PM - Moscone West 2016 Oracle Exadata and Oracle Exalogic are designed from the ground up with optimizations in software and hardware to deliver superfast performance for mission-critical applications such as Oracle E-Business Suite. Oracle E-Business Suite applications run three to eight times as fast on the Oracle Exadata/Oracle Exalogic platform in standard benchmark tests. Besides performance, customers benefit from simplified support, enhanced manageability, and the ability to consolidate multiple Oracle E-Business Suite instances. Attend this session to understand best practices for Oracle E-Business Suite deployment on Oracle Exalogic and Oracle Exadata through customer case studies. Learn how adopting the Exa* platform increases efficiency, simplifies scaling, and boosts performance for peak loads. CON8716 - Web Services and SOA Integration Options for Oracle E-Business SuiteRekha Ayothi, Veshaal Singh, Oracle Thursday, Oct 4, 11:15 AM - 12:15 PM - Moscone West 2016 This Oracle development session provides a deep dive into a subset of the Web services and SOA-related integration options available to Oracle E-Business Suite systems integrators. It offers a technical look at Oracle E-Business Suite Integrated SOA Gateway, Oracle SOA Suite, Oracle Application Adapters for Data Integration for Oracle E-Business Suite, and other Web services options for integrating Oracle E-Business Suite with other applications. Systems integrators and developers will get an overview of the latest integration capabilities and technologies available out of the box with Oracle E-Business Suite and possibly a sneak preview of upcoming functionality and features. CON9030 - Recommendations for Oracle E-Business Suite Performance TuningIsam Alyousfi, Samer Barakat, Oracle Thursday, Oct 4, 11:15 AM - 12:15 PM - Moscone West 2018 Need to squeeze more performance out of your existing servers? This packed Oracle development session summarizes practical tips and lessons learned from performance-tuning and benchmarking the world’s largest Oracle E-Business Suite environments. Apps sysadmins will learn concrete tips and techniques for identifying and resolving performance bottlenecks on all layers, with special attention to application- and database-tier servers. Learn about tuning Oracle Forms, Oracle Concurrent Manager, Apache, and Oracle Discoverer. Track down memory leaks and other issues at the Java and JVM layers. The session also covers Oracle E-Business Suite product-level tuning, including Oracle Workflow, Oracle Order Management, Oracle Payroll, and other modules. CON3429 - Using Oracle ADF with Oracle E-Business Suite: The Full Integration ViewSiva Puthurkattil, Lake County; Juan Camilo Ruiz, Sara Woodhull, Oracle Thursday, Oct 4, 11:15 AM - 12:15 PM - Moscone West 3003 Oracle E-Business Suite delivers functionality for handling the core business of your organization. However, user requirements and new technologies are driving an emerging need to implement new types of user interfaces for these applications. This session provides an overview of how to use Oracle Application Development Framework (Oracle ADF) to deliver cutting-edge Web 2.0 and mobile rich user interfaces that front existing Oracle E-Business Suite processes, and it also explores all the existing types of integration between the two worlds. CON9020 - Integrating Oracle E-Business Suite with Oracle Identity Management SolutionsSunil Ghosh, Elke Phelps, Oracle Thursday, Oct 4, 12:45 PM - 1:45 PM - Moscone West 2016 Need to integrate Oracle E-Business Suite with Microsoft Windows Kerberos, Active Directory, CA Netegrity SiteMinder, or other third-party authentication systems? Want to understand your options when Oracle Premier Support for Oracle Single Sign-On ends in December 2011? This Oracle Development session covers the latest certified integrations with Oracle Access Manager 11g and Oracle Internet Directory 11g, which can be used individually or as bridges for integrating with third-party authentication solutions. The session presents an architectural overview of how Oracle Access Manager, its WebGate and AccessGate components, and Oracle Internet Directory work together, with implications for Oracle Discoverer, Oracle Portal, and other Oracle Fusion identity management products. CON9019 - Troubleshooting, Diagnosing, and Optimizing Oracle E-Business Suite TechnologyGustavo Jimenez, Oracle Thursday, Oct 4, 2:15 PM - 3:15 PM - Moscone West 2016 This session covers how you can proactively diagnose Oracle E-Business Suite applications, including extensions built with Oracle Fusion Middleware technologies such as Oracle Application Development Framework (Oracle ADF) and Oracle WebCenter to catch potential issues in the middle tier before they become more serious. Topics include debugging, logging infrastructure, warning signs, performance tuning, information required when logging service requests, general JVM optimization, and an overall picture of all the moving parts that make it possible for Oracle E-Business Suite to isolate and fix problems. Also learn how Oracle Diagnostics Framework will help prevent downtime caused by failures. CON9031 - The Top 10 Things You Can Do to Secure Your Oracle E-Business Suite InstanceEric Bing, Erik Graversen, Oracle Thursday, Oct 4, 2:15 PM - 3:15 PM - Moscone West 2018 Learn the top 10 things you can do to secure your applications and your sensitive data. This Oracle development session for system administrators and security professionals explores some of the most important and overlooked things you can do to secure your Oracle E-Business Suite instance. It also covers data masking and other mechanisms for protecting sensitive data. Special Interest Groups (SIG) Some of our most senior staff have been invited to participate on the following SIG meetings as guest speakers: SIG10525 - OAUG - Archive & Purge SIGBrian Bent - Pre-Sales Engineer, TierData, Inc. Sunday, Sep 30, 10:30 AM - 12:00 PM - Moscone West 3011 The Archive and Purge SIG is an organization in which users can share their experiences and solicit functional and technical advice on archiving and purging data in Oracle E-Business Suite. This session provides an opportunity for users to network and share best practices, tips, and tricks. Guest: Oracle E-Business Suite Database Performance, Archive & Purging - Q&A SessionIsam Alyousfi, Senior Director, Applications Performance, Oracle SIG10547 - OAUG - Oracle E-Business (EBS) Applications Technology SIGSrini Chavali - IT Director, Cummins Inc Sunday, Sep 30, 10:30 AM - 12:00 PM - Moscone West 3018 The general purpose of the EBS Applications Technology SIG is to inform and educate its members about current and future components of the tech stack as they relate to Oracle E-Business Suite. Attend this meeting for networking and education and to share best practices. Guest: Oracle E-Business Suite Technology Certification Roadmap - Presentation and Q&ASteven Chan, Sr. Director, Applications Technology Group, Oracle SIG10559 - OAUG - User Management SIGSusan Behn - VP of Oracle Delivery, Infosemantics, Inc. Sunday, Sep 30, 10:30 AM - 12:00 PM - Moscone West 3024 The E-Business Suite User Management SIG focuses on the components of user management that enable Oracle E-Business Suite users to define administrative functions and manage users’ access to functions and data based on roles within an organization—rather than the user’s individual identity—which is referred to as role-based access control (RBAC). This meeting includes an introduction to Oracle User Management that covers the Oracle User Management building blocks and presents an example of creating a security policy.Guest: Security and User Management - Q&A SessionEric Bing, Sr. Director, EBS Security, OracleSara Woodhull, Principal Product Manager, Applications Technology Group, Oracle SIG10515 - OAUG – Upgrade SIGBarbara Matthews - Consultant, On Call DBASandra Vucinic, VLAD Group, Inc. Sunday, Sep 30, 12:00 PM - 2:00 PM - Moscone West 3009 This Upgrade SIG session starts with a business meeting and then features a Q&A panel discussion on Oracle E-Business Suite upgrade topics. The session• Reviews Upgrade SIG goals and objectives• Provides answers, during the Q&A session, to questions related to Oracle E-Business Suite upgrades• Shares “real world” experiences, tips, and techniques for Oracle E-Business Suite upgrades to Release 12.1. Guest: Oracle E-Business Suite Upgrade - Q&A SessionAnne Carlson - Sr. Director, Oracle E-Business Suite Product Strategy, OracleUdayan Parvate - Director, EBS Release Engineering, OracleSuzana Ferrari, Sr. Principal Consultant, OracleIsam Alyousfi, Sr. Director, Applications Performance, Oracle SIG10552 - OAUG - Oracle E-Business Suite SIGDonna Rosentrater - Manager, Global Sourcing & Procurement Systems, TJX Sunday, Sep 30, 12:15 PM - 1:45 PM - Moscone West 3020 The E-Business Suite SIG, affiliated with OAUG, supports Oracle E-Business Suite users through networking, education, and sharing of best practices. This SIG meeting will feature a general discussion of Oracle E-Business Suite product strategies in Release 12 and migration to Oracle Fusion Applications. Guest: Oracle E-Business Suite - Q&A SessionJeanne Lowell, Vice President, EBS Product Strategy, OracleNadia Bendjedou, Sr. Director, Product Strategy, Oracle SIG10556 - OAUG - SysAdmin SIGRandy Giefer - Sr Systems and Security Architect, Solution Beacon, LLC Sunday, Sep 30, 12:15 PM - 1:45 PM - Moscone West 3022 The SysAdmin SIG provides a forum in which OAUG members and participants can share updates, tips, and successful practices relating to system administration in an Oracle applications environment. The SysAdmin SIG strives to enable system administrators to become more effective and efficient in their jobs by providing them with access to people and information that can increase their system administration knowledge and experience. Attend this meeting to network, share best practices, and benefit from educational content. Guest: Oracle E-Business Suite 12.2 Online Patching- Presentation and Q&AKevin Hudson, Sr. Director, Applications Technology Group, Oracle SIG10553 - OAUG - Database SIGMichael Brown - Senior DBA, COLIBRI LTD LC Sunday, Sep 30, 2:00 PM - 3:15 PM - Moscone West 3020 The OAUG Database SIG provides an opportunity for applications database administrators to learn from and share their experiences with supporting the various Oracle applications environments. This session will include a brief business meeting followed by a short presentation. It will end with an open discussion among the attendees about items of interest to those present. Guest: Oracle E-Business Suite Database Performance - Presentation and Q&AIsam Alyousfi, Sr. Director, Applications Performance, Oracle Meet the Experts We're planning two round-table discussions where you can review your questions with senior E-Business Suite ATG staff: MTE9648 - Meet the Experts for Oracle E-Business Suite: Planning Your Upgrade Jeanne Lowell - VP, EBS Product Strategy, Oracle John Abraham - Sr. Principal Product Manager, Oracle Nadia Bendjedou - Sr. Director - Product Strategy, Oracle Anne Carlson - Sr. Director, Applications Technology Group, Oracle Udayan Parvate - Director, EBS Release Engineering, Oracle Isam Alyousfi, Sr. Director, Applications Performance, Oracle Monday, Oct 1, 3:15 PM - 4:15 PM - Moscone West 2001A Don’t miss this Oracle Applications Meet the Experts session with experts who specialize in Oracle E-Business Suite upgrade best practices. This is the place where attendees can have informal and semistructured but open one-on-one discussions with Strategy and Development regarding Oracle Applications strategy and your specific business and IT strategy. The experts will be available to discuss the value of the latest releases and share insights into the best path for your enterprise, so come ready with your questions. Space is limited, so make sure you register. MTE9649 - Meet the Oracle E-Business Suite Tools and Technology Experts Lisa Parekh - Vice President, Technology Integration, Oracle Steven Chan - Sr. Director, Oracle Elke Phelps - Sr. Principal Product Manager, Applications Technology Group, Oracle Max Arderius - Manager, Applications Technology Group, Oracle Tuesday, Oct 2, 1:15 PM - 2:15 PM - Moscone West 2001A Don’t miss this Oracle Applications Meet the Experts session with experts who specialize in Oracle E-Business Suite technology. This is the place where attendees can have informal and semistructured but open one-on-one discussions with Strategy and Development regarding Oracle Applications strategy and your specific business and IT strategy. The experts will be available to discuss the value of the latest releases and share insights into the best path for your enterprise, so come ready with your questions. Space is limited, so make sure you register. Demos We have five booths in the exhibition demogrounds this year, where you can try ATG technologies firsthand and get your questions answered. Please stop by and meet our staff at the following locations: Advanced Architecture and Technology Stack for Oracle E-Business Suite (W-067) New User Productivity Capabilities in Oracle E-Business Suite (W-065) End-to-End Management of Oracle E-Business Suite (W-063) Oracle E-Business Suite 12.1 Technical Upgrade Best Practices (W-066) SOA-Based Integration for Oracle E-Business Suite (W-064)

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• C# 5 Async, Part 1: Simplifying Asynchrony – That for which we await

  - by Reed

  Today’s announcement at PDC of the future directions C# is taking excite me greatly.  The new Visual Studio Async CTP is amazing.  Asynchronous code – code which frustrates and demoralizes even the most advanced of developers, is taking a huge leap forward in terms of usability.  This is handled by building on the Task functionality in .NET 4, as well as the addition of two new keywords being added to the C# language: async and await. This core of the new asynchronous functionality is built upon three key features.  First is the Task functionality in .NET 4, and based on Task and Task<TResult>.  While Task was intended to be the primary means of asynchronous programming with .NET 4, the .NET Framework was still based mainly on the Asynchronous Pattern and the Event-based Asynchronous Pattern. The .NET Framework added functionality and guidance for wrapping existing APIs into a Task based API, but the framework itself didn’t really adopt Task or Task<TResult> in any meaningful way.  The CTP shows that, going forward, this is changing. One of the three key new features coming in C# is actually a .NET Framework feature.  Nearly every asynchronous API in the .NET Framework has been wrapped into a new, Task-based method calls.  In the CTP, this is done via as external assembly (AsyncCtpLibrary.dll) which uses Extension Methods to wrap the existing APIs.  However, going forward, this will be handled directly within the Framework.  This will have a unifying effect throughout the .NET Framework.  This is the first building block of the new features for asynchronous programming: Going forward, all asynchronous operations will work via a method that returns Task or Task<TResult> The second key feature is the new async contextual keyword being added to the language.  The async keyword is used to declare an asynchronous function, which is a method that either returns void, a Task, or a Task<T>. Inside the asynchronous function, there must be at least one await expression.  This is a new C# keyword (await) that is used to automatically take a series of statements and break it up to potentially use discontinuous evaluation.  This is done by using await on any expression that evaluates to a Task or Task<T>. For example, suppose we want to download a webpage as a string.  There is a new method added to WebClient: Task<string> WebClient.DownloadStringTaskAsync(Uri).  Since this returns a Task<string> we can use it within an asynchronous function.  Suppose, for example, that we wanted to do something similar to my asynchronous Task example – download a web page asynchronously and check to see if it supports XHTML 1.0, then report this into a TextBox.  This could be done like so: private async void button1_Click(object sender, RoutedEventArgs e) { string url = "http://reedcopsey.com"; string content = await new WebClient().DownloadStringTaskAsync(url); this.textBox1.Text = string.Format("Page {0} supports XHTML 1.0: {1}", url, content.Contains("XHTML 1.0")); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Let’s walk through what’s happening here, step by step.  By adding the async contextual keyword to the method definition, we are able to use the await keyword on our WebClient.DownloadStringTaskAsync method call. When the user clicks this button, the new method (Task<string> WebClient.DownloadStringTaskAsync(string)) is called, which returns a Task<string>.  By adding the await keyword, the runtime will call this method that returns Task<string>, and execution will return to the caller at this point.  This means that our UI is not blocked while the webpage is downloaded.  Instead, the UI thread will “await” at this point, and let the WebClient do it’s thing asynchronously. When the WebClient finishes downloading the string, the user interface’s synchronization context will automatically be used to “pick up” where it left off, and the Task<string> returned from DownloadStringTaskAsync is automatically unwrapped and set into the content variable.  At this point, we can use that and set our text box content. There are a couple of key points here: Asynchronous functions are declared with the async keyword, and contain one or more await expressions In addition to the obvious benefits of shorter, simpler code – there are some subtle but tremendous benefits in this approach.  When the execution of this asynchronous function continues after the first await statement, the initial synchronization context is used to continue the execution of this function.  That means that we don’t have to explicitly marshal the call that sets textbox1.Text back to the UI thread – it’s handled automatically by the language and framework!  Exception handling around asynchronous method calls also just works. I’d recommend every C# developer take a look at the documentation on the new Asynchronous Programming for C# and Visual Basic page, download the Visual Studio Async CTP, and try it out.

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• New Book From Luís Abreu: ASP.NET 4.0 – The Complete Course (Portuguese)

  - by Paulo Morgado

  Thsi book, with several practical examples, presents how to build web applications using ASP.NET 4.0. Starts by introducing the framework to build pages and controls and gradually introduces all the new features available. More compact that its previous versions  (part of the content was moved to FCA’s site in the form of apendices), this new book gives emphasis to to the new features in ASP.NET 4.0 and targets both developers new to ASP.NET and developers moving from previous versions of ASP.NET. This time there’s good new for Brazilian readers. The book will be distributed in Brazil by: Zamboni Comércio de Livros Ltda. Av.Parada Pinto, 1476 São Paulo – SP Telf. / Fax: +55 11 2233-2333 E-mail: [email protected] Our book (LINQ Com C# (Portuguese)) isn’t still distributed in Brazil, but, if you want it, you can always try that distributer.

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• Node.js Adventure - When Node Flying in Wind

  - by Shaun

  In the first post of this series I mentioned some popular modules in the community, such as underscore, async, etc.. I also listed a module named “Wind (zh-CN)”, which is created by one of my friend, Jeff Zhao (zh-CN). Now I would like to use a separated post to introduce this module since I feel it brings a new async programming style in not only Node.js but JavaScript world. If you know or heard about the new feature in C# 5.0 called “async and await”, or you learnt F#, you will find the “Wind” brings the similar async programming experience in JavaScript. By using “Wind”, we can write async code that looks like the sync code. The callbacks, async stats and exceptions will be handled by “Wind” automatically and transparently.   What’s the Problem: Dense “Callback” Phobia Let’s firstly back to my second post in this series. As I mentioned in that post, when we wanted to read some records from SQL Server we need to open the database connection, and then execute the query. In Node.js all IO operation are designed as async callback pattern which means when the operation was done, it will invoke a function which was taken from the last parameter. For example the database connection opening code would be like this. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: } 8: }); And then if we need to query the database the code would be like this. It nested in the previous function. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: conn.queryRaw(command, function(error, results) { 8: if(error) { 9: // failed to execute this command 10: } 11: else { 12: // records retrieved successfully 13: } 14: }; 15: } 16: }); Assuming if we need to copy some data from this database to another then we need to open another connection and execute the command within the function under the query function. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: conn.queryRaw(command, function(error, results) { 8: if(error) { 9: // failed to execute this command 10: } 11: else { 12: // records retrieved successfully 13: target.open(targetConnectionString, function(error, t_conn) { 14: if(error) { 15: // connect failed 16: } 17: else { 18: t_conn.queryRaw(copy_command, function(error, results) { 19: if(error) { 20: // copy failed 21: } 22: else { 23: // and then, what do you want to do now... 24: } 25: }; 26: } 27: }; 28: } 29: }; 30: } 31: }); This is just an example. In the real project the logic would be more complicated. This means our application might be messed up and the business process will be fragged by many callback functions. I would like call this “Dense Callback Phobia”. This might be a challenge how to make code straightforward and easy to read, something like below. 1: try 2: { 3: // open source connection 4: var s_conn = sqlConnect(s_connectionString); 5: // retrieve data 6: var results = sqlExecuteCommand(s_conn, s_command); 7: 8: // open target connection 9: var t_conn = sqlConnect(t_connectionString); 10: // prepare the copy command 11: var t_command = getCopyCommand(results); 12: // execute the copy command 13: sqlExecuteCommand(s_conn, t_command); 14: } 15: catch (ex) 16: { 17: // error handling 18: }   What’s the Problem: Sync-styled Async Programming Similar as the previous problem, the callback-styled async programming model makes the upcoming operation as a part of the current operation, and mixed with the error handling code. So it’s very hard to understand what on earth this code will do. And since Node.js utilizes non-blocking IO mode, we cannot invoke those operations one by one, as they will be executed concurrently. For example, in this post when I tried to copy the records from Windows Azure SQL Database (a.k.a. WASD) to Windows Azure Table Storage, if I just insert the data into table storage one by one and then print the “Finished” message, I will see the message shown before the data had been copied. This is because all operations were executed at the same time. In order to make the copy operation and print operation executed synchronously I introduced a module named “async” and the code was changed as below. 1: async.forEach(results.rows, 2: function (row, callback) { 3: var resource = { 4: "PartitionKey": row[1], 5: "RowKey": row[0], 6: "Value": row[2] 7: }; 8: client.insertEntity(tableName, resource, function (error) { 9: if (error) { 10: callback(error); 11: } 12: else { 13: console.log("entity inserted."); 14: callback(null); 15: } 16: }); 17: }, 18: function (error) { 19: if (error) { 20: error["target"] = "insertEntity"; 21: res.send(500, error); 22: } 23: else { 24: console.log("all done."); 25: res.send(200, "Done!"); 26: } 27: }); It ensured that the “Finished” message will be printed when all table entities had been inserted. But it cannot promise that the records will be inserted in sequence. It might be another challenge to make the code looks like in sync-style? 1: try 2: { 3: forEach(row in rows) { 4: var entity = { /* ... */ }; 5: tableClient.insert(tableName, entity); 6: } 7:  8: console.log("Finished"); 9: } 10: catch (ex) { 11: console.log(ex); 12: }   How “Wind” Helps “Wind” is a JavaScript library which provides the control flow with plain JavaScript for asynchronous programming (and more) without additional pre-compiling steps. It’s available in NPM so that we can install it through “npm install wind”. Now let’s create a very simple Node.js application as the example. This application will take some website URLs from the command arguments and tried to retrieve the body length and print them in console. Then at the end print “Finish”. I’m going to use “request” module to make the HTTP call simple so I also need to install by the command “npm install request”. The code would be like this. 1: var request = require("request"); 2:  3: // get the urls from arguments, the first two arguments are `node.exe` and `fetch.js` 4: var args = process.argv.splice(2); 5:  6: // main function 7: var main = function() { 8: for(var i = 0; i < args.length; i++) { 9: // get the url 10: var url = args[i]; 11: // send the http request and try to get the response and body 12: request(url, function(error, response, body) { 13: if(!error && response.statusCode == 200) { 14: // log the url and the body length 15: console.log( 16: "%s: %d.", 17: response.request.uri.href, 18: body.length); 19: } 20: else { 21: // log error 22: console.log(error); 23: } 24: }); 25: } 26: 27: // finished 28: console.log("Finished"); 29: }; 30:  31: // execute the main function 32: main(); Let’s execute this application. (I made them in multi-lines for better reading.) 1: node fetch.js 2: "http://www.igt.com/us-en.aspx" 3: "http://www.igt.com/us-en/games.aspx" 4: "http://www.igt.com/us-en/cabinets.aspx" 5: "http://www.igt.com/us-en/systems.aspx" 6: "http://www.igt.com/us-en/interactive.aspx" 7: "http://www.igt.com/us-en/social-gaming.aspx" 8: "http://www.igt.com/support.aspx" Below is the output. As you can see the finish message was printed at the beginning, and the pages’ length retrieved in a different order than we specified. This is because in this code the request command, console logging command are executed asynchronously and concurrently. Now let’s introduce “Wind” to make them executed in order, which means it will request the websites one by one, and print the message at the end.   First of all we need to import the “Wind” package and make sure the there’s only one global variant named “Wind”, and ensure it’s “Wind” instead of “wind”. 1: var Wind = require("wind");   Next, we need to tell “Wind” which code will be executed asynchronously so that “Wind” can control the execution process. In this case the “request” operation executed asynchronously so we will create a “Task” by using a build-in helps function in “Wind” named Wind.Async.Task.create. 1: var requestBodyLengthAsync = function(url) { 2: return Wind.Async.Task.create(function(t) { 3: request(url, function(error, response, body) { 4: if(error || response.statusCode != 200) { 5: t.complete("failure", error); 6: } 7: else { 8: var data = 9: { 10: uri: response.request.uri.href, 11: length: body.length 12: }; 13: t.complete("success", data); 14: } 15: }); 16: }); 17: }; The code above created a “Task” from the original request calling code. In “Wind” a “Task” means an operation will be finished in some time in the future. A “Task” can be started by invoke its start() method, but no one knows when it actually will be finished. The Wind.Async.Task.create helped us to create a task. The only parameter is a function where we can put the actual operation in, and then notify the task object it’s finished successfully or failed by using the complete() method. In the code above I invoked the request method. If it retrieved the response successfully I set the status of this task as “success” with the URL and body length. If it failed I set this task as “failure” and pass the error out.   Next, we will change the main() function. In “Wind” if we want a function can be controlled by Wind we need to mark it as “async”. This should be done by using the code below. 1: var main = eval(Wind.compile("async", function() { 2: })); When the application is running, Wind will detect “eval(Wind.compile(“async”, function” and generate an anonymous code from the body of this original function. Then the application will run the anonymous code instead of the original one. In our example the main function will be like this. 1: var main = eval(Wind.compile("async", function() { 2: for(var i = 0; i < args.length; i++) { 3: try 4: { 5: var result = $await(requestBodyLengthAsync(args[i])); 6: console.log( 7: "%s: %d.", 8: result.uri, 9: result.length); 10: } 11: catch (ex) { 12: console.log(ex); 13: } 14: } 15: 16: console.log("Finished"); 17: })); As you can see, when I tried to request the URL I use a new command named “$await”. It tells Wind, the operation next to $await will be executed asynchronously, and the main thread should be paused until it finished (or failed). So in this case, my application will be pause when the first response was received, and then print its body length, then try the next one. At the end, print the finish message.   Finally, execute the main function. The full code would be like this. 1: var request = require("request"); 2: var Wind = require("wind"); 3:  4: var args = process.argv.splice(2); 5:  6: var requestBodyLengthAsync = function(url) { 7: return Wind.Async.Task.create(function(t) { 8: request(url, function(error, response, body) { 9: if(error || response.statusCode != 200) { 10: t.complete("failure", error); 11: } 12: else { 13: var data = 14: { 15: uri: response.request.uri.href, 16: length: body.length 17: }; 18: t.complete("success", data); 19: } 20: }); 21: }); 22: }; 23:  24: var main = eval(Wind.compile("async", function() { 25: for(var i = 0; i < args.length; i++) { 26: try 27: { 28: var result = $await(requestBodyLengthAsync(args[i])); 29: console.log( 30: "%s: %d.", 31: result.uri, 32: result.length); 33: } 34: catch (ex) { 35: console.log(ex); 36: } 37: } 38: 39: console.log("Finished"); 40: })); 41:  42: main().start();   Run our new application. At the beginning we will see the compiled and generated code by Wind. Then we can see the pages were requested one by one, and at the end the finish message was printed. Below is the code Wind generated for us. As you can see the original code, the output code were shown. 1: // Original: 2: function () { 3: for(var i = 0; i < args.length; i++) { 4: try 5: { 6: var result = $await(requestBodyLengthAsync(args[i])); 7: console.log( 8: "%s: %d.", 9: result.uri, 10: result.length); 11: } 12: catch (ex) { 13: console.log(ex); 14: } 15: } 16: 17: console.log("Finished"); 18: } 19:  20: // Compiled: 21: /* async << function () { */ (function () { 22: var _builder_$0 = Wind.builders["async"]; 23: return _builder_$0.Start(this, 24: _builder_$0.Combine( 25: _builder_$0.Delay(function () { 26: /* var i = 0; */ var i = 0; 27: /* for ( */ return _builder_$0.For(function () { 28: /* ; i < args.length */ return i < args.length; 29: }, function () { 30: /* ; i ++) { */ i ++; 31: }, 32: /* try { */ _builder_$0.Try( 33: _builder_$0.Delay(function () { 34: /* var result = $await(requestBodyLengthAsync(args[i])); */ return _builder_$0.Bind(requestBodyLengthAsync(args[i]), function (result) { 35: /* console.log("%s: %d.", result.uri, result.length); */ console.log("%s: %d.", result.uri, result.length); 36: return _builder_$0.Normal(); 37: }); 38: }), 39: /* } catch (ex) { */ function (ex) { 40: /* console.log(ex); */ console.log(ex); 41: return _builder_$0.Normal(); 42: /* } */ }, 43: null 44: ) 45: /* } */ ); 46: }), 47: _builder_$0.Delay(function () { 48: /* console.log("Finished"); */ console.log("Finished"); 49: return _builder_$0.Normal(); 50: }) 51: ) 52: ); 53: /* } */ })   How Wind Works Someone may raise a big concern when you find I utilized “eval” in my code. Someone may assume that Wind utilizes “eval” to execute some code dynamically while “eval” is very low performance. But I would say, Wind does NOT use “eval” to run the code. It only use “eval” as a flag to know which code should be compiled at runtime. When the code was firstly been executed, Wind will check and find “eval(Wind.compile(“async”, function”. So that it knows this function should be compiled. Then it utilized parse-js to analyze the inner JavaScript and generated the anonymous code in memory. Then it rewrite the original code so that when the application was running it will use the anonymous one instead of the original one. Since the code generation was done at the beginning of the application was started, in the future no matter how long our application runs and how many times the async function was invoked, it will use the generated code, no need to generate again. So there’s no significant performance hurt when using Wind.   Wind in My Previous Demo Let’s adopt Wind into one of my previous demonstration and to see how it helps us to make our code simple, straightforward and easy to read and understand. In this post when I implemented the functionality that copied the records from my WASD to table storage, the logic would be like this. 1, Open database connection. 2, Execute a query to select all records from the table. 3, Recreate the table in Windows Azure table storage. 4, Create entities from each of the records retrieved previously, and then insert them into table storage. 5, Finally, show message as the HTTP response. But as the image below, since there are so many callbacks and async operations, it’s very hard to understand my logic from the code. Now let’s use Wind to rewrite our code. First of all, of course, we need the Wind package. Then we need to include the package files into project and mark them as “Copy always”. Add the Wind package into the source code. Pay attention to the variant name, you must use “Wind” instead of “wind”. 1: var express = require("express"); 2: var async = require("async"); 3: var sql = require("node-sqlserver"); 4: var azure = require("azure"); 5: var Wind = require("wind"); Now we need to create some async functions by using Wind. All async functions should be wrapped so that it can be controlled by Wind which are open database, retrieve records, recreate table (delete and create) and insert entity in table. Below are these new functions. All of them are created by using Wind.Async.Task.create. 1: sql.openAsync = function (connectionString) { 2: return Wind.Async.Task.create(function (t) { 3: sql.open(connectionString, function (error, conn) { 4: if (error) { 5: t.complete("failure", error); 6: } 7: else { 8: t.complete("success", conn); 9: } 10: }); 11: }); 12: }; 13:  14: sql.queryAsync = function (conn, query) { 15: return Wind.Async.Task.create(function (t) { 16: conn.queryRaw(query, function (error, results) { 17: if (error) { 18: t.complete("failure", error); 19: } 20: else { 21: t.complete("success", results); 22: } 23: }); 24: }); 25: }; 26:  27: azure.recreateTableAsync = function (tableName) { 28: return Wind.Async.Task.create(function (t) { 29: client.deleteTable(tableName, function (error, successful, response) { 30: console.log("delete table finished"); 31: client.createTableIfNotExists(tableName, function (error, successful, response) { 32: console.log("create table finished"); 33: if (error) { 34: t.complete("failure", error); 35: } 36: else { 37: t.complete("success", null); 38: } 39: }); 40: }); 41: }); 42: }; 43:  44: azure.insertEntityAsync = function (tableName, entity) { 45: return Wind.Async.Task.create(function (t) { 46: client.insertEntity(tableName, entity, function (error, entity, response) { 47: if (error) { 48: t.complete("failure", error); 49: } 50: else { 51: t.complete("success", null); 52: } 53: }); 54: }); 55: }; Then in order to use these functions we will create a new function which contains all steps for data copying. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: } 4: catch (ex) { 5: console.log(ex); 6: res.send(500, "Internal error."); 7: } 8: })); Let’s execute steps one by one with the “$await” keyword introduced by Wind so that it will be invoked in sequence. First is to open the database connection. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: } 7: catch (ex) { 8: console.log(ex); 9: res.send(500, "Internal error."); 10: } 11: })); Then retrieve all records from the database connection. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: } 10: catch (ex) { 11: console.log(ex); 12: res.send(500, "Internal error."); 13: } 14: })); After recreated the table, we need to create the entities and insert them into table storage. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage one by one 14: for (var i = 0; i < results.rows.length; i++) { 15: var entity = { 16: "PartitionKey": results.rows[i][1], 17: "RowKey": results.rows[i][0], 18: "Value": results.rows[i][2] 19: }; 20: $await(azure.insertEntityAsync(tableName, entity)); 21: console.log("entity inserted"); 22: } 23: } 24: } 25: catch (ex) { 26: console.log(ex); 27: res.send(500, "Internal error."); 28: } 29: })); Finally, send response back to the browser. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage one by one 14: for (var i = 0; i < results.rows.length; i++) { 15: var entity = { 16: "PartitionKey": results.rows[i][1], 17: "RowKey": results.rows[i][0], 18: "Value": results.rows[i][2] 19: }; 20: $await(azure.insertEntityAsync(tableName, entity)); 21: console.log("entity inserted"); 22: } 23: // send response 24: console.log("all done"); 25: res.send(200, "All done!"); 26: } 27: } 28: catch (ex) { 29: console.log(ex); 30: res.send(500, "Internal error."); 31: } 32: })); If we compared with the previous code we will find now it became more readable and much easy to understand. It’s very easy to know what this function does even though without any comments. When user go to URL “/was/copyRecords” we will execute the function above. The code would be like this. 1: app.get("/was/copyRecords", function (req, res) { 2: copyRecords(req, res).start(); 3: }); And below is the logs printed in local compute emulator console. As we can see the functions executed one by one and then finally the response back to me browser.   Scaffold Functions in Wind Wind provides not only the async flow control and compile functions, but many scaffold methods as well. We can build our async code more easily by using them. I’m going to introduce some basic scaffold functions here. In the code above I created some functions which wrapped from the original async function such as open database, create table, etc.. All of them are very similar, created a task by using Wind.Async.Task.create, return error or result object through Task.complete function. In fact, Wind provides some functions for us to create task object from the original async functions. If the original async function only has a callback parameter, we can use Wind.Async.Binding.fromCallback method to get the task object directly. For example the code below returned the task object which wrapped the file exist check function. 1: var Wind = require("wind"); 2: var fs = require("fs"); 3:  4: fs.existsAsync = Wind.Async.Binding.fromCallback(fs.exists); In Node.js a very popular async function pattern is that, the first parameter in the callback function represent the error object, and the other parameters is the return values. In this case we can use another build-in function in Wind named Wind.Async.Binding.fromStandard. For example, the open database function can be created from the code below. 1: sql.openAsync = Wind.Async.Binding.fromStandard(sql.open); 2:  3: /* 4: sql.openAsync = function (connectionString) { 5: return Wind.Async.Task.create(function (t) { 6: sql.open(connectionString, function (error, conn) { 7: if (error) { 8: t.complete("failure", error); 9: } 10: else { 11: t.complete("success", conn); 12: } 13: }); 14: }); 15: }; 16: */ When I was testing the scaffold functions under Wind.Async.Binding I found for some functions, such as the Azure SDK insert entity function, cannot be processed correctly. So I personally suggest writing the wrapped method manually.   Another scaffold method in Wind is the parallel tasks coordination. In this example, the steps of open database, retrieve records and recreated table should be invoked one by one, but it can be executed in parallel when copying data from database to table storage. In Wind there’s a scaffold function named Task.whenAll which can be used here. Task.whenAll accepts a list of tasks and creates a new task. It will be returned only when all tasks had been completed, or any errors occurred. For example in the code below I used the Task.whenAll to make all copy operation executed at the same time. 1: var copyRecordsInParallel = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage in parallal 14: var tasks = new Array(results.rows.length); 15: for (var i = 0; i < results.rows.length; i++) { 16: var entity = { 17: "PartitionKey": results.rows[i][1], 18: "RowKey": results.rows[i][0], 19: "Value": results.rows[i][2] 20: }; 21: tasks[i] = azure.insertEntityAsync(tableName, entity); 22: } 23: $await(Wind.Async.Task.whenAll(tasks)); 24: // send response 25: console.log("all done"); 26: res.send(200, "All done!"); 27: } 28: } 29: catch (ex) { 30: console.log(ex); 31: res.send(500, "Internal error."); 32: } 33: })); 34:  35: app.get("/was/copyRecordsInParallel", function (req, res) { 36: copyRecordsInParallel(req, res).start(); 37: });   Besides the task creation and coordination, Wind supports the cancellation solution so that we can send the cancellation signal to the tasks. It also includes exception solution which means any exceptions will be reported to the caller function.   Summary In this post I introduced a Node.js module named Wind, which created by my friend Jeff Zhao. As you can see, different from other async library and framework, adopted the idea from F# and C#, Wind utilizes runtime code generation technology to make it more easily to write async, callback-based functions in a sync-style way. By using Wind there will be almost no callback, and the code will be very easy to understand. Currently Wind is still under developed and improved. There might be some problems but the author, Jeff, should be very happy and enthusiastic to learn your problems, feedback, suggestion and comments. You can contact Jeff by - Email: [email protected] - Group: https://groups.google.com/d/forum/windjs - GitHub: https://github.com/JeffreyZhao/wind/issues   Source code can be download here.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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• New features of C# 4.0

  This article covers New features of C# 4.0. Article has been divided into below sections. Introduction. Dynamic Lookup. Named and Optional Arguments. Features for COM interop. Variance. Relationship with Visual Basic. Resources. Other interested readings… 22 New Features of Visual Studio 2008 for .NET Professionals 50 New Features of SQL Server 2008 IIS 7.0 New features Introduction It is now close to a year since Microsoft Visual C# 3.0 shipped as part of Visual Studio 2008. In the VS Managed Languages team we are hard at work on creating the next version of the language (with the unsurprising working title of C# 4.0), and this document is a first public description of the planned language features as we currently see them. Please be advised that all this is in early stages of production and is subject to change. Part of the reason for sharing our plans in public so early is precisely to get the kind of feedback that will cause us to improve the final product before it rolls out. Simultaneously with the publication of this whitepaper, a first public CTP (community technology preview) of Visual Studio 2010 is going out as a Virtual PC image for everyone to try. Please use it to play and experiment with the features, and let us know of any thoughts you have. We ask for your understanding and patience working with very early bits, where especially new or newly implemented features do not have the quality or stability of a final product. The aim of the CTP is not to give you a productive work environment but to give you the best possible impression of what we are working on for the next release. The CTP contains a number of walkthroughs, some of which highlight the new language features of C# 4.0. Those are excellent for getting a hands-on guided tour through the details of some common scenarios for the features. You may consider this whitepaper a companion document to these walkthroughs, complementing them with a focus on the overall language features and how they work, as opposed to the specifics of the concrete scenarios. C# 4.0 The major theme for C# 4.0 is dynamic programming. Increasingly, objects are “dynamic” in the sense that their structure and behavior is not captured by a static type, or at least not one that the compiler knows about when compiling your program. Some examples include a. objects from dynamic programming languages, such as Python or Ruby b. COM objects accessed through IDispatch c. ordinary .NET types accessed through reflection d. objects with changing structure, such as HTML DOM objects While C# remains a statically typed language, we aim to vastly improve the interaction with such objects. A secondary theme is co-evolution with Visual Basic. Going forward we will aim to maintain the individual character of each language, but at the same time important new features should be introduced in both languages at the same time. They should be differentiated more by style and feel than by feature set. The new features in C# 4.0 fall into four groups: Dynamic lookup Dynamic lookup allows you to write method, operator and indexer calls, property and field accesses, and even object invocations which bypass the C# static type checking and instead gets resolved at runtime. Named and optional parameters Parameters in C# can now be specified as optional by providing a default value for them in a member declaration. When the member is invoked, optional arguments can be omitted. Furthermore, any argument can be passed by parameter name instead of position. COM specific interop features Dynamic lookup as well as named and optional parameters both help making programming against COM less painful than today. On top of that, however, we are adding a number of other small features that further improve the interop experience. Variance It used to be that an IEnumerable<string> wasn’t an IEnumerable<object>. Now it is – C# embraces type safe “co-and contravariance” and common BCL types are updated to take advantage of that. Dynamic Lookup Dynamic lookup allows you a unified approach to invoking things dynamically. With dynamic lookup, when you have an object in your hand you do not need to worry about whether it comes from COM, IronPython, the HTML DOM or reflection; you just apply operations to it and leave it to the runtime to figure out what exactly those operations mean for that particular object. This affords you enormous flexibility, and can greatly simplify your code, but it does come with a significant drawback: Static typing is not maintained for these operations. A dynamic object is assumed at compile time to support any operation, and only at runtime will you get an error if it wasn’t so. Oftentimes this will be no loss, because the object wouldn’t have a static type anyway, in other cases it is a tradeoff between brevity and safety. In order to facilitate this tradeoff, it is a design goal of C# to allow you to opt in or opt out of dynamic behavior on every single call. The dynamic type C# 4.0 introduces a new static type called dynamic. When you have an object of type dynamic you can “do things to it” that are resolved only at runtime: dynamic d = GetDynamicObject(…); d.M(7); The C# compiler allows you to call a method with any name and any arguments on d because it is of type dynamic. At runtime the actual object that d refers to will be examined to determine what it means to “call M with an int” on it. The type dynamic can be thought of as a special version of the type object, which signals that the object can be used dynamically. It is easy to opt in or out of dynamic behavior: any object can be implicitly converted to dynamic, “suspending belief” until runtime. Conversely, there is an “assignment conversion” from dynamic to any other type, which allows implicit conversion in assignment-like constructs: dynamic d = 7; // implicit conversion int i = d; // assignment conversion Dynamic operations Not only method calls, but also field and property accesses, indexer and operator calls and even delegate invocations can be dispatched dynamically: dynamic d = GetDynamicObject(…); d.M(7); // calling methods d.f = d.P; // getting and settings fields and properties d[“one”] = d[“two”]; // getting and setting thorugh indexers int i = d + 3; // calling operators string s = d(5,7); // invoking as a delegate The role of the C# compiler here is simply to package up the necessary information about “what is being done to d”, so that the runtime can pick it up and determine what the exact meaning of it is given an actual object d. Think of it as deferring part of the compiler’s job to runtime. The result of any dynamic operation is itself of type dynamic. Runtime lookup At runtime a dynamic operation is dispatched according to the nature of its target object d: COM objects If d is a COM object, the operation is dispatched dynamically through COM IDispatch. This allows calling to COM types that don’t have a Primary Interop Assembly (PIA), and relying on COM features that don’t have a counterpart in C#, such as indexed properties and default properties. Dynamic objects If d implements the interface IDynamicObject d itself is asked to perform the operation. Thus by implementing IDynamicObject a type can completely redefine the meaning of dynamic operations. This is used intensively by dynamic languages such as IronPython and IronRuby to implement their own dynamic object models. It will also be used by APIs, e.g. by the HTML DOM to allow direct access to the object’s properties using property syntax. Plain objects Otherwise d is a standard .NET object, and the operation will be dispatched using reflection on its type and a C# “runtime binder” which implements C#’s lookup and overload resolution semantics at runtime. This is essentially a part of the C# compiler running as a runtime component to “finish the work” on dynamic operations that was deferred by the static compiler. Example Assume the following code: dynamic d1 = new Foo(); dynamic d2 = new Bar(); string s; d1.M(s, d2, 3, null); Because the receiver of the call to M is dynamic, the C# compiler does not try to resolve the meaning of the call. Instead it stashes away information for the runtime about the call. This information (often referred to as the “payload”) is essentially equivalent to: “Perform an instance method call of M with the following arguments: 1. a string 2. a dynamic 3. a literal int 3 4. a literal object null” At runtime, assume that the actual type Foo of d1 is not a COM type and does not implement IDynamicObject. In this case the C# runtime binder picks up to finish the overload resolution job based on runtime type information, proceeding as follows: 1. Reflection is used to obtain the actual runtime types of the two objects, d1 and d2, that did not have a static type (or rather had the static type dynamic). The result is Foo for d1 and Bar for d2. 2. Method lookup and overload resolution is performed on the type Foo with the call M(string,Bar,3,null) using ordinary C# semantics. 3. If the method is found it is invoked; otherwise a runtime exception is thrown. Overload resolution with dynamic arguments Even if the receiver of a method call is of a static type, overload resolution can still happen at runtime. This can happen if one or more of the arguments have the type dynamic: Foo foo = new Foo(); dynamic d = new Bar(); var result = foo.M(d); The C# runtime binder will choose between the statically known overloads of M on Foo, based on the runtime type of d, namely Bar. The result is again of type dynamic. The Dynamic Language Runtime An important component in the underlying implementation of dynamic lookup is the Dynamic Language Runtime (DLR), which is a new API in .NET 4.0. The DLR provides most of the infrastructure behind not only C# dynamic lookup but also the implementation of several dynamic programming languages on .NET, such as IronPython and IronRuby. Through this common infrastructure a high degree of interoperability is ensured, but just as importantly the DLR provides excellent caching mechanisms which serve to greatly enhance the efficiency of runtime dispatch. To the user of dynamic lookup in C#, the DLR is invisible except for the improved efficiency. However, if you want to implement your own dynamically dispatched objects, the IDynamicObject interface allows you to interoperate with the DLR and plug in your own behavior. This is a rather advanced task, which requires you to understand a good deal more about the inner workings of the DLR. For API writers, however, it can definitely be worth the trouble in order to vastly improve the usability of e.g. a library representing an inherently dynamic domain. Open issues There are a few limitations and things that might work differently than you would expect. · The DLR allows objects to be created from objects that represent classes. However, the current implementation of C# doesn’t have syntax to support this. · Dynamic lookup will not be able to find extension methods. Whether extension methods apply or not depends on the static context of the call (i.e. which using clauses occur), and this context information is not currently kept as part of the payload. · Anonymous functions (i.e. lambda expressions) cannot appear as arguments to a dynamic method call. The compiler cannot bind (i.e. “understand”) an anonymous function without knowing what type it is converted to. One consequence of these limitations is that you cannot easily use LINQ queries over dynamic objects: dynamic collection = …; var result = collection.Select(e => e + 5); If the Select method is an extension method, dynamic lookup will not find it. Even if it is an instance method, the above does not compile, because a lambda expression cannot be passed as an argument to a dynamic operation. There are no plans to address these limitations in C# 4.0. Named and Optional Arguments Named and optional parameters are really two distinct features, but are often useful together. Optional parameters allow you to omit arguments to member invocations, whereas named arguments is a way to provide an argument using the name of the corresponding parameter instead of relying on its position in the parameter list. Some APIs, most notably COM interfaces such as the Office automation APIs, are written specifically with named and optional parameters in mind. Up until now it has been very painful to call into these APIs from C#, with sometimes as many as thirty arguments having to be explicitly passed, most of which have reasonable default values and could be omitted. Even in APIs for .NET however you sometimes find yourself compelled to write many overloads of a method with different combinations of parameters, in order to provide maximum usability to the callers. Optional parameters are a useful alternative for these situations. Optional parameters A parameter is declared optional simply by providing a default value for it: public void M(int x, int y = 5, int z = 7); Here y and z are optional parameters and can be omitted in calls: M(1, 2, 3); // ordinary call of M M(1, 2); // omitting z – equivalent to M(1, 2, 7) M(1); // omitting both y and z – equivalent to M(1, 5, 7) Named and optional arguments C# 4.0 does not permit you to omit arguments between commas as in M(1,,3). This could lead to highly unreadable comma-counting code. Instead any argument can be passed by name. Thus if you want to omit only y from a call of M you can write: M(1, z: 3); // passing z by name or M(x: 1, z: 3); // passing both x and z by name or even M(z: 3, x: 1); // reversing the order of arguments All forms are equivalent, except that arguments are always evaluated in the order they appear, so in the last example the 3 is evaluated before the 1. Optional and named arguments can be used not only with methods but also with indexers and constructors. Overload resolution Named and optional arguments affect overload resolution, but the changes are relatively simple: A signature is applicable if all its parameters are either optional or have exactly one corresponding argument (by name or position) in the call which is convertible to the parameter type. Betterness rules on conversions are only applied for arguments that are explicitly given – omitted optional arguments are ignored for betterness purposes. If two signatures are equally good, one that does not omit optional parameters is preferred. M(string s, int i = 1); M(object o); M(int i, string s = “Hello”); M(int i); M(5); Given these overloads, we can see the working of the rules above. M(string,int) is not applicable because 5 doesn’t convert to string. M(int,string) is applicable because its second parameter is optional, and so, obviously are M(object) and M(int). M(int,string) and M(int) are both better than M(object) because the conversion from 5 to int is better than the conversion from 5 to object. Finally M(int) is better than M(int,string) because no optional arguments are omitted. Thus the method that gets called is M(int). Features for COM interop Dynamic lookup as well as named and optional parameters greatly improve the experience of interoperating with COM APIs such as the Office Automation APIs. In order to remove even more of the speed bumps, a couple of small COM-specific features are also added to C# 4.0. Dynamic import Many COM methods accept and return variant types, which are represented in the PIAs as object. In the vast majority of cases, a programmer calling these methods already knows the static type of a returned object from context, but explicitly has to perform a cast on the returned value to make use of that knowledge. These casts are so common that they constitute a major nuisance. In order to facilitate a smoother experience, you can now choose to import these COM APIs in such a way that variants are instead represented using the type dynamic. In other words, from your point of view, COM signatures now have occurrences of dynamic instead of object in them. This means that you can easily access members directly off a returned object, or you can assign it to a strongly typed local variable without having to cast. To illustrate, you can now say excel.Cells[1, 1].Value = "Hello"; instead of ((Excel.Range)excel.Cells[1, 1]).Value2 = "Hello"; and Excel.Range range = excel.Cells[1, 1]; instead of Excel.Range range = (Excel.Range)excel.Cells[1, 1]; Compiling without PIAs Primary Interop Assemblies are large .NET assemblies generated from COM interfaces to facilitate strongly typed interoperability. They provide great support at design time, where your experience of the interop is as good as if the types where really defined in .NET. However, at runtime these large assemblies can easily bloat your program, and also cause versioning issues because they are distributed independently of your application. The no-PIA feature allows you to continue to use PIAs at design time without having them around at runtime. Instead, the C# compiler will bake the small part of the PIA that a program actually uses directly into its assembly. At runtime the PIA does not have to be loaded. Omitting ref Because of a different programming model, many COM APIs contain a lot of reference parameters. Contrary to refs in C#, these are typically not meant to mutate a passed-in argument for the subsequent benefit of the caller, but are simply another way of passing value parameters. It therefore seems unreasonable that a C# programmer should have to create temporary variables for all such ref parameters and pass these by reference. Instead, specifically for COM methods, the C# compiler will allow you to pass arguments by value to such a method, and will automatically generate temporary variables to hold the passed-in values, subsequently discarding these when the call returns. In this way the caller sees value semantics, and will not experience any side effects, but the called method still gets a reference. Open issues A few COM interface features still are not surfaced in C#. Most notably these include indexed properties and default properties. As mentioned above these will be respected if you access COM dynamically, but statically typed C# code will still not recognize them. There are currently no plans to address these remaining speed bumps in C# 4.0. Variance An aspect of generics that often comes across as surprising is that the following is illegal: IList<string> strings = new List<string>(); IList<object> objects = strings; The second assignment is disallowed because strings does not have the same element type as objects. There is a perfectly good reason for this. If it were allowed you could write: objects[0] = 5; string s = strings[0]; Allowing an int to be inserted into a list of strings and subsequently extracted as a string. This would be a breach of type safety. However, there are certain interfaces where the above cannot occur, notably where there is no way to insert an object into the collection. Such an interface is IEnumerable<T>. If instead you say: IEnumerable<object> objects = strings; There is no way we can put the wrong kind of thing into strings through objects, because objects doesn’t have a method that takes an element in. Variance is about allowing assignments such as this in cases where it is safe. The result is that a lot of situations that were previously surprising now just work. Covariance In .NET 4.0 the IEnumerable<T> interface will be declared in the following way: public interface IEnumerable<out T> : IEnumerable { IEnumerator<T> GetEnumerator(); } public interface IEnumerator<out T> : IEnumerator { bool MoveNext(); T Current { get; } } The “out” in these declarations signifies that the T can only occur in output position in the interface – the compiler will complain otherwise. In return for this restriction, the interface becomes “covariant” in T, which means that an IEnumerable<A> is considered an IEnumerable<B> if A has a reference conversion to B. As a result, any sequence of strings is also e.g. a sequence of objects. This is useful e.g. in many LINQ methods. Using the declarations above: var result = strings.Union(objects); // succeeds with an IEnumerable<object> This would previously have been disallowed, and you would have had to to some cumbersome wrapping to get the two sequences to have the same element type. Contravariance Type parameters can also have an “in” modifier, restricting them to occur only in input positions. An example is IComparer<T>: public interface IComparer<in T> { public int Compare(T left, T right); } The somewhat baffling result is that an IComparer<object> can in fact be considered an IComparer<string>! It makes sense when you think about it: If a comparer can compare any two objects, it can certainly also compare two strings. This property is referred to as contravariance. A generic type can have both in and out modifiers on its type parameters, as is the case with the Func<…> delegate types: public delegate TResult Func<in TArg, out TResult>(TArg arg); Obviously the argument only ever comes in, and the result only ever comes out. Therefore a Func<object,string> can in fact be used as a Func<string,object>. Limitations Variant type parameters can only be declared on interfaces and delegate types, due to a restriction in the CLR. Variance only applies when there is a reference conversion between the type arguments. For instance, an IEnumerable<int> is not an IEnumerable<object> because the conversion from int to object is a boxing conversion, not a reference conversion. Also please note that the CTP does not contain the new versions of the .NET types mentioned above. In order to experiment with variance you have to declare your own variant interfaces and delegate types. COM Example Here is a larger Office automation example that shows many of the new C# features in action. using System; using System.Diagnostics; using System.Linq; using Excel = Microsoft.Office.Interop.Excel; using Word = Microsoft.Office.Interop.Word; class Program { static void Main(string[] args) { var excel = new Excel.Application(); excel.Visible = true; excel.Workbooks.Add(); // optional arguments omitted excel.Cells[1, 1].Value = "Process Name"; // no casts; Value dynamically excel.Cells[1, 2].Value = "Memory Usage"; // accessed var processes = Process.GetProcesses() .OrderByDescending(p =&gt; p.WorkingSet) .Take(10); int i = 2; foreach (var p in processes) { excel.Cells[i, 1].Value = p.ProcessName; // no casts excel.Cells[i, 2].Value = p.WorkingSet; // no casts i++; } Excel.Range range = excel.Cells[1, 1]; // no casts Excel.Chart chart = excel.ActiveWorkbook.Charts. Add(After: excel.ActiveSheet); // named and optional arguments chart.ChartWizard( Source: range.CurrentRegion, Title: "Memory Usage in " + Environment.MachineName); //named+optional chart.ChartStyle = 45; chart.CopyPicture(Excel.XlPictureAppearance.xlScreen, Excel.XlCopyPictureFormat.xlBitmap, Excel.XlPictureAppearance.xlScreen); var word = new Word.Application(); word.Visible = true; word.Documents.Add(); // optional arguments word.Selection.Paste(); } } The code is much more terse and readable than the C# 3.0 counterpart. Note especially how the Value property is accessed dynamically. This is actually an indexed property, i.e. a property that takes an argument; something which C# does not understand. However the argument is optional. Since the access is dynamic, it goes through the runtime COM binder which knows to substitute the default value and call the indexed property. Thus, dynamic COM allows you to avoid accesses to the puzzling Value2 property of Excel ranges. Relationship with Visual Basic A number of the features introduced to C# 4.0 already exist or will be introduced in some form or other in Visual Basic: · Late binding in VB is similar in many ways to dynamic lookup in C#, and can be expected to make more use of the DLR in the future, leading to further parity with C#. · Named and optional arguments have been part of Visual Basic for a long time, and the C# version of the feature is explicitly engineered with maximal VB interoperability in mind. · NoPIA and variance are both being introduced to VB and C# at the same time. VB in turn is adding a number of features that have hitherto been a mainstay of C#. As a result future versions of C# and VB will have much better feature parity, for the benefit of everyone. Resources All available resources concerning C# 4.0 can be accessed through the C# Dev Center. Specifically, this white paper and other resources can be found at the Code Gallery site. Enjoy! span.fullpost {display:none;}

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• EBS + 11g Database Upgrade Best Practices Whitepaper Available

  - by Steven Chan

  I returned from OAUG/Collaborate with a cold and multiple overlapping development crises.  Fun.  Now that those are (mostly) out of the way, it's time to get back to clearing out my article backlog.  Premier Support for the 10gR2 database ends in July 2010.  If you haven't already started planning your 11g database upgrade, we recommend that you start soon.  We have certified both the 11gR1 (11.1.0.7) and 11gR2 (11.2.0.1) databases with Oracle E-Business Suite; see this blog's Certification summary to links to articles with the details.Our Applications Performance Group has reminded me that they have a whitepaper loaded with practical tips intended to make your 11g database upgrade easier.  No vacuous marketing rhetoric here -- this is strictly written for DBAs.  A must-read if you haven't already upgraded to either 11gR1 or 11gR2, and highly recommended even if you have.  You can download this whitepaper here:Upgrade to 11g Performance Best Practices (PDF, 184K)

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• Status of stack based languages

  - by Andrea

  I have recently become curious about Factor, which, as far as I understand, is the most practical stack based language around. Forth seems not to be used much these days - I think it is because it was meant to be used on its own, instead of inside an operating system, although ports of course exist. It is also pretty low level. Joy is essentially dead, as the author stated that it does not make sense to mantain it in spite of adopting Factor. The fact is that Factor itself does not seem much developed today. The GitHub repo does not seem very active, and a lot of stuff languishes in unmantained. So, are there any other languages of this type that are more actively mantained? Are any in production use?

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• Developer Training – Various Options for Maximum Benefit – Part 4

  - by pinaldave

  Developer Training - Importance and Significance - Part 1 Developer Training – Employee Morals and Ethics – Part 2 Developer Training – Difficult Questions and Alternative Perspective - Part 3 Developer Training – Various Options for Developer Training – Part 4 Developer Training – A Conclusive Summary- Part 5 If you have been reading this series, by now you are aware of all the pros and cons that can come along with training.  We’ve asked and answered hard questions, and investigated them “whys” and “hows” of training.  Now it is time to talk about all the different kinds of training that are out there! On Job Training The most common type of training is on the job training.  Everyone receives this kind of education – even experts who come in to consult have to be taught where the printer, pens, and copy machines are.  If you are thinking about more concrete topics, though, on the job training can be some of the easiest to come across.  Picture this: someone in the company whom you really admire is hard at work on a project.  You come up to them and ask to help them out – if they are a busy developer, the odds are that they will say “yes, please!”   If you phrase your question as an offer of help, you can receive training without ever putting someone in the awkward position of acting as a mentor.  However, some people may want the task of being a mentor.  It can never hurt to ask.  Most people will be more than willing to pass their knowledge along. Extreme Programming If your company and coworkers are willing, you can even investigate Extreme Programming.  This is a type of programming that allows small teams to quickly develop code and products that are released with almost immediate user feedback.  You can find more information at http://www.extremeprogramming.org/.  If this is something your company could use, suggest it to your supervisor.  Even if they say no, it will make it clear that you are a go-getter who is interested in new and exciting projects.  If the answer is yes, then you have the opportunity to get some of the best on the job training around. In Person Training Click on Image to Enlarge When you say the word “training,” most people’s minds go back to the classroom, an image they are familiar with.  While training doesn’t always have to be in a traditional setting, because it is so familiar it can also be the most valuable type of training.  There are many ways to get training through a live instructor.  Some companies may be willing to send a representative to you, where employees will get training, sometimes food and coffee, and a live instructor who can answer questions immediately.  Sometimes these trainers are also able to do consultations at the same time, which can invaluable to a company.  If you are the one to asks your supervisor for a training session that can also be turned into a consultation, you may stick in their minds as an incredibly dedicated employee.  If you can’t find a representative, local colleges can also be a good resource for free or cheap classes – or they may have representatives coming who are willing to take on a few more students. Benefits of On Demand Developer Training Of course, you can often get the best of all these types of training with online or On Demand training.  You can get the benefit of a live instructor who is willing to answer questions (although in this case, usually through e-mail or other online venues), there are often real-world examples to follow along – like on the job training – and best of all you can learn whenever you have the time or need.  Did a problem with your server come up at midnight when all your supervisors are safe at home and probably in bed?  No problem!  On Demand training is especially useful if you need to slow down, pause, or rewind a training session.  Not even a real-life instructor can do that! When I was writing this blog post, I felt that each of the subject, which I have covered can be blog posts of itself. However, I wanted to keep the the blog post concise and so touch based on three major training aspects 1) On Job Training 2) In Person Training and 3) Online training. Here is the question for you – is there any other kind of training methods available, which are effective and one should consider it? If yes, what are those, I may write a follow up blog post on the same subject next week. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Developer Training, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Initial review of Developer's Guide to Collections in Microsoft® .NET

  - by TATWORTH

  The code is well illustrated by diagrams. The approach is practical. The code is well commented, however the C# code samples would be better had they been fully Style Cop compliant. I am looking forward to reviewing the rest of this excellent book. I recommend this book to all C# and VB.NET Development teams. I concur with the author who states that the book is not for learning C# or VB.NET. It is an excellent book for C# or VB.NET developers to extend their knowledge of the Dot Net framework. To buy a copy, please go to http://shop.oreilly.com/product/0790145317193.do

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• O&rsquo;Reilly Deal of the Day 14/Aug/2014 - RESTful Web APIs

  - by TATWORTH

  Originally posted on: http://geekswithblogs.net/TATWORTH/archive/2014/08/14/orsquoreilly-deal-of-the-day-14aug2014---restful-web-apis.aspxToday’s half-price Deal of the Day from O’Reilly at http://shop.oreilly.com/product/0636920028468.do?code=DEAL is RESTful Web APIs. “The popularity of REST in recent years has led to tremendous growth in almost-RESTful APIs that don’t include many of the architecture’s benefits. With this practical guide, you’ll learn what it takes to design usable REST APIs that evolve over time. By focusing on solutions that cross a variety of domains, this book shows you how to create powerful and secure applications, using the tools designed for the world’s most successful distributed computing system: the World Wide Web.”

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• To ORM or Not to ORM. That is the question&hellip;

  - by Patrick Liekhus

  UPDATE:  Thanks for the feedback and comments.  I have adjusted my table below with your recommendations.  I had missed a point or two. I wanted to do a series on creating an entire project using the EDMX XAF code generation and the SpecFlow BDD Easy Test tools discussed in my earlier posts, but I thought it would be appropriate to start with a simple comparison and reasoning on why I choose to use these tools. Let’s start by defining the term ORM, or Object-Relational Mapping.  According to Wikipedia it is defined as the following: Object-relational mapping (ORM, O/RM, and O/R mapping) in computer software is a programming technique for converting data between incompatible type systems in object-oriented programming languages. This creates, in effect, a "virtual object database" that can be used from within the programming language. Why should you care?  Basically it allows you to map your business objects in code to their persistence layer behind them. And better yet, why would you want to do this?  Let me outline it in the following points: Development speed.  No more need to map repetitive tasks query results to object members.  Once the map is created the code is rendered for you. Persistence portability.  The ORM knows how to map SQL specific syntax for the persistence engine you choose.  It does not matter if it is SQL Server, Oracle and another database of your choosing. Standard/Boilerplate code is simplified.  The basic CRUD operations are consistent and case use database metadata for basic operations. So how does this help?  Well, let’s compare some of the ORM tools that I have used and/or researched.  I have been interested in ORM for some time now.  My ORM of choice for a long time was NHibernate and I still believe it has a strong case in some business situations.  However, you have to take business considerations into account and the law of diminishing returns.  Because of these two factors, my recent activity and experience has been around DevExpress eXpress Persistence Objects (XPO).  The primary reason for this is because they have the DevExpress eXpress Application Framework (XAF) that sits on top of XPO.  With this added value, the data model can be created (either database first of code first) and the Web and Windows client can be created from these maps.  While out of the box they provide some simple list and detail screens, you can verify easily extend and modify these to your liking.  DevExpress has done a tremendous job of providing enough framework while also staying out of the way when you need to extend it.  This sounds worse than it really is.  What I mean by this is that if you choose to follow DevExpress coding style and recommendations, the hooks and extension points provided allow you to do some pretty heavy lifting while also not worrying about the basics. I have put together a list of the top features that I have used to compare the limited list of ORM’s that I have exposure with.  Again, the biggest selling point in my opinion is that XPO is just a solid as any of the other ORM’s but with the added layer of XAF they become unstoppable.  And then couple that with the EDMX modeling tools and code generation, it becomes a no brainer. Designer Features Entity Framework NHibernate Fluent w/ Nhibernate Telerik OpenAccess DevExpress XPO DevExpress XPO/XAF plus Liekhus Tools Uses XML to map relationships - Yes - - -   Visual class designer interface Yes - - - - Yes Management integrated w/ Visual Studio Yes - - Yes - Yes Supports schema first approach Yes - - Yes - Yes Supports model first approach Yes - - Yes Yes Yes Supports code first approach Yes Yes Yes Yes Yes Yes Attribute driven coding style Yes - Yes - Yes Yes                 I have a very small team and limited resources with a lot of responsibilities.  In order to keep up with our customers, we must rely on tools like these.  We use the EDMX tool so that we can create a visual representation of the applications with our customers.  Second, we rely on the code generation so that we can focus on the business problems at hand and not whether a field is mapped correctly.  This keeps us from requiring as many junior level developers on our team.  I have also worked on multiple teams where they believed in writing their own “framework”.  In my experiences and opinion this is not the route to take unless you have a team dedicated to supporting just the framework.  Each time that I have worked on custom frameworks, the framework eventually becomes old, out dated and full of “performance” enhancements specific to one or two requirements.  With an ORM, there are a lot smarter people than me working on the bigger issue of persistence and performance.  Again, my recommendation would be to use an available framework and get to working on your business domain problems.  If your coding is not making money for you, why are you working on it?  Do you really need to be writing query to object member code again and again? Thanks

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• Test-Drive ASP.NET MVC Review

  - by Ben Griswold

  A few years back I started dallying with test-driven development, but I never fully committed to the practice. This wasn’t because I didn’t believe in the value of TDD; it was more a matter of not completely understanding how to incorporate “test first” into my everyday development. Back in my web forms days, I could point fingers at the framework for my ignorance and laziness. After all, web forms weren’t exactly designed for testability so who could blame me for not embracing TDD in those conditions, right? But when I switched to ASP.NET MVC and quickly found myself fresh out of excuses and it became instantly clear that it was time to get my head around red-green-refactor once and for all or I would regretfully miss out on one of the biggest selling points the new framework had to offer. I have previously written about how I learned ASP.NET MVC. It was primarily hands on learning but I did read a couple of ASP.NET MVC books along the way. The books I read dedicated a chapter or two to TDD and they certainly addressed the benefits of TDD and how MVC was designed with testability in mind, but TDD was merely an afterthought compared to, well, teaching one how to code the model, view and controller. This approach made some sense, and I learned a bunch about MVC from those books, but when it came to TDD the books were just a teaser and an opportunity missed.  But then I got lucky – Jonathan McCracken contacted me and asked if I’d review his book, Test-Drive ASP.NET MVC, and it was just what I needed to get over the TDD hump. As the title suggests, Test-Drive ASP.NET MVC takes a different approach to learning MVC as it focuses on testing right from the very start. McCracken wastes no time and swiftly familiarizes us with the framework by building out a trivial Quote-O-Matic application and then dedicates the better part of his book to testing first – first by explaining TDD and then coding a full-featured Getting Organized application inspired by David Allen’s popular book, Getting Things Done. If you are a learn-by-example kind of coder (like me), you will instantly appreciate and enjoy McCracken’s style – its fast-moving, pragmatic and focused on only the most relevant information required to get you going with ASP.NET MVC and TDD. The book continues with the test-first theme but McCracken moves away from the sample application and incorporates other practical skills like persisting models with NHibernate, leveraging Inversion of Control with the IControllerFactory and building a RESTful web service. What I most appreciated about this section was McCracken’s use of and praise for open source libraries like Rhino Mocks, SQLite and StructureMap (to name just a few) and productivity tools like ReSharper, Web Platform Installer and ASP.NET SQL Server Setup Wizard.  McCracken’s emphasis on real world, pragmatic development was clearly demonstrated in every tool choice, straight-forward code block and developer tip. Whether one is already familiar with the tools/tips or not, McCracken’s thought process is easily understood and appreciated. The final section of the book walks the reader through security and deployment – everything from error handling and logging with ELMAH, to ASP.NET Health Monitoring, to using MSBuild with automated builds, to the deployment  of ASP.NET MVC to various web environments. These chapters, like those prior, offer enough information and explanation to simply help you get the job done.  Do I believe Test-Drive ASP.NET MVC will turn you into an expert MVC developer overnight?  Well, no.  I don’t think any book can make that claim.  If that were possible, I think book list prices would skyrocket!  That said, Test-Drive ASP.NET MVC provides a solid foundation and a unique (and dare I say necessary) approach to learning ASP.NET MVC.  Along the way McCracken shares loads of very practical software development tips and references numerous tools and libraries. The bottom line is it’s a great ASP.NET MVC primer – if you’re new to ASP.NET MVC it’s just what you need to get started.  Do I believe Test-Drive ASP.NET MVC will give you everything you need to start employing TDD in your everyday development?  Well, I used to think that learning TDD required a lot of practice and, if you’re lucky enough, the guidance of a mentor or coach.  I used to think that one couldn’t learn TDD from a book alone. Well, I’m still no pro, but I’m testing first now and Jonathan McCracken and his book, Test-Drive ASP.NET MVC, played a big part in making this happen.  If you are an MVC developer and a TDD newb, Test-Drive ASP.NET MVC is just the book for you.

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• What's a good open source java project for students to hack on?

  - by Evan Grim

  I'm working with a professor to develop a course teaching practical software development tools and methodology. We're looking for a sample code base that we can use for hands-on experience in each of the topics and as the basis for a semester-long project where students will work in a team to implement a feature or fix bugs. Here are some basic guidelines for the project that we'd like to come close to meeting: java based, ~50K SLOC, uses ant, depends upon some external library, has a test suite (preferably jUnit), friendly for development within eclipse, actively developed with a substantial history available within a version control system (such as subversion), the more "coolness" factor the better (to motivate the students), and preferably with some kind of user interface (e.g.: not just a library).

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• ASP.NET Frameworks and Raw Throughput Performance

  - by Rick Strahl

  A few days ago I had a curious thought: With all these different technologies that the ASP.NET stack has to offer, what's the most efficient technology overall to return data for a server request? When I started this it was mere curiosity rather than a real practical need or result. Different tools are used for different problems and so performance differences are to be expected. But still I was curious to see how the various technologies performed relative to each just for raw throughput of the request getting to the endpoint and back out to the client with as little processing in the actual endpoint logic as possible (aka Hello World!). I want to clarify that this is merely an informal test for my own curiosity and I'm sharing the results and process here because I thought it was interesting. It's been a long while since I've done any sort of perf testing on ASP.NET, mainly because I've not had extremely heavy load requirements and because overall ASP.NET performs very well even for fairly high loads so that often it's not that critical to test load performance. This post is not meant to make a point  or even come to a conclusion which tech is better, but just to act as a reference to help understand some of the differences in perf and give a starting point to play around with this yourself. I've included the code for this simple project, so you can play with it and maybe add a few additional tests for different things if you like. Source Code on GitHub I looked at this data for these technologies: ASP.NET Web API ASP.NET MVC WebForms ASP.NET WebPages ASMX AJAX Services  (couldn't get AJAX/JSON to run on IIS8 ) WCF Rest Raw ASP.NET HttpHandlers It's quite a mixed bag, of course and the technologies target different types of development. What started out as mere curiosity turned into a bit of a head scratcher as the results were sometimes surprising. What I describe here is more to satisfy my curiosity more than anything and I thought it interesting enough to discuss on the blog :-) First test: Raw Throughput The first thing I did is test raw throughput for the various technologies. This is the least practical test of course since you're unlikely to ever create the equivalent of a 'Hello World' request in a real life application. The idea here is to measure how much time a 'NOP' request takes to return data to the client. So for this request I create the simplest Hello World request that I could come up for each tech. Http Handler The first is the lowest level approach which is an HTTP handler. public class Handler : IHttpHandler { public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/plain"; context.Response.Write("Hello World. Time is: " + DateTime.Now.ToString()); } public bool IsReusable { get { return true; } } } WebForms Next I added a couple of ASPX pages - one using CodeBehind and one using only a markup page. The CodeBehind page simple does this in CodeBehind without any markup in the ASPX page: public partial class HelloWorld_CodeBehind : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { Response.Write("Hello World. Time is: " + DateTime.Now.ToString() ); Response.End(); } } while the Markup page only contains some static output via an expression:<%@ Page Language="C#" AutoEventWireup="false" CodeBehind="HelloWorld_Markup.aspx.cs" Inherits="AspNetFrameworksPerformance.HelloWorld_Markup" %> Hello World. Time is <%= DateTime.Now %> ASP.NET WebPages WebPages is the freestanding Razor implementation of ASP.NET. Here's the simple HelloWorld.cshtml page:Hello World @DateTime.Now WCF REST WCF REST was the token REST implementation for ASP.NET before WebAPI and the inbetween step from ASP.NET AJAX. I'd like to forget that this technology was ever considered for production use, but I'll include it here. Here's an OperationContract class: [ServiceContract(Namespace = "")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class WcfService { [OperationContract] [WebGet] public Stream HelloWorld() { var data = Encoding.Unicode.GetBytes("Hello World" + DateTime.Now.ToString()); var ms = new MemoryStream(data); // Add your operation implementation here return ms; } } WCF REST can return arbitrary results by returning a Stream object and a content type. The code above turns the string result into a stream and returns that back to the client. ASP.NET AJAX (ASMX Services) I also wanted to test ASP.NET AJAX services because prior to WebAPI this is probably still the most widely used AJAX technology for the ASP.NET stack today. Unfortunately I was completely unable to get this running on my Windows 8 machine. Visual Studio 2012  removed adding of ASP.NET AJAX services, and when I tried to manually add the service and configure the script handler references it simply did not work - I always got a SOAP response for GET and POST operations. No matter what I tried I always ended up getting XML results even when explicitly adding the ScriptHandler. So, I didn't test this (but the code is there - you might be able to test this on a Windows 7 box). ASP.NET MVC Next up is probably the most popular ASP.NET technology at the moment: MVC. Here's the small controller: public class MvcPerformanceController : Controller { public ActionResult Index() { return View(); } public ActionResult HelloWorldCode() { return new ContentResult() { Content = "Hello World. Time is: " + DateTime.Now.ToString() }; } } ASP.NET WebAPI Next up is WebAPI which looks kind of similar to MVC. Except here I have to use a StringContent result to return the response: public class WebApiPerformanceController : ApiController { [HttpGet] public HttpResponseMessage HelloWorldCode() { return new HttpResponseMessage() { Content = new StringContent("Hello World. Time is: " + DateTime.Now.ToString(), Encoding.UTF8, "text/plain") }; } } Testing Take a minute to think about each of the technologies… and take a guess which you think is most efficient in raw throughput. The fastest should be pretty obvious, but the others - maybe not so much. The testing I did is pretty informal since it was mainly to satisfy my curiosity - here's how I did this: I used Apache Bench (ab.exe) from a full Apache HTTP installation to run and log the test results of hitting the server. ab.exe is a small executable that lets you hit a URL repeatedly and provides counter information about the number of requests, requests per second etc. ab.exe and the batch file are located in the \LoadTests folder of the project. An ab.exe command line  looks like this: ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorld which hits the specified URL 100,000 times with a load factor of 20 concurrent requests. This results in output like this:   It's a great way to get a quick and dirty performance summary. Run it a few times to make sure there's not a large amount of varience. You might also want to do an IISRESET to clear the Web Server. Just make sure you do a short test run to warm up the server first - otherwise your first run is likely to be skewed downwards. ab.exe also allows you to specify headers and provide POST data and many other things if you want to get a little more fancy. Here all tests are GET requests to keep it simple. I ran each test: 100,000 iterations Load factor of 20 concurrent connections IISReset before starting A short warm up run for API and MVC to make sure startup cost is mitigated Here is the batch file I used for the test: IISRESET REM make sure you add REM C:\Program Files (x86)\Apache Software Foundation\Apache2.2\bin REM to your path so ab.exe can be found REM Warm up ab.exe -n100 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldJsonab.exe -n100 -c20 http://localhost/aspnetperf/api/HelloWorldJson ab.exe -n100 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorld ab.exe -n100000 -c20 http://localhost/aspnetperf/handler.ashx > handler.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/HelloWorld_CodeBehind.aspx > AspxCodeBehind.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/HelloWorld_Markup.aspx > AspxMarkup.txt ab.exe -n100000 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorld > Wcf.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldCode > Mvc.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorld > WebApi.txt I ran each of these tests 3 times and took the average score for Requests/second, with the machine otherwise idle. I did see a bit of variance when running many tests but the values used here are the medians. Part of this has to do with the fact I ran the tests on my local machine - result would probably more consistent running the load test on a separate machine hitting across the network. I ran these tests locally on my laptop which is a Dell XPS with quad core Sandibridge I7-2720QM @ 2.20ghz and a fast SSD drive on Windows 8. CPU load during tests ran to about 70% max across all 4 cores (IOW, it wasn't overloading the machine). Ideally you can try running these tests on a separate machine hitting the local machine. If I remember correctly IIS 7 and 8 on client OSs don't throttle so the performance here should be Results Ok, let's cut straight to the chase. Below are the results from the tests… It's not surprising that the handler was fastest. But it was a bit surprising to me that the next fastest was WebForms and especially Web Forms with markup over a CodeBehind page. WebPages also fared fairly well. MVC and WebAPI are a little slower and the slowest by far is WCF REST (which again I find surprising). As mentioned at the start the raw throughput tests are not overly practical as they don't test scripting performance for the HTML generation engines or serialization performances of the data engines. All it really does is give you an idea of the raw throughput for the technology from time of request to reaching the endpoint and returning minimal text data back to the client which indicates full round trip performance. But it's still interesting to see that Web Forms performs better in throughput than either MVC, WebAPI or WebPages. It'd be interesting to try this with a few pages that actually have some parsing logic on it, but that's beyond the scope of this throughput test. But what's also amazing about this test is the sheer amount of traffic that a laptop computer is handling. Even the slowest tech managed 5700 requests a second, which is one hell of a lot of requests if you extrapolate that out over a 24 hour period. Remember these are not static pages, but dynamic requests that are being served. Another test - JSON Data Service Results The second test I used a JSON result from several of the technologies. I didn't bother running WebForms and WebPages through this test since that doesn't make a ton of sense to return data from the them (OTOH, returning text from the APIs didn't make a ton of sense either :-) In these tests I have a small Person class that gets serialized and then returned to the client. The Person class looks like this: public class Person { public Person() { Id = 10; Name = "Rick"; Entered = DateTime.Now; } public int Id { get; set; } public string Name { get; set; } public DateTime Entered { get; set; } } Here are the updated handler classes that use Person: Handler public class Handler : IHttpHandler { public void ProcessRequest(HttpContext context) { var action = context.Request.QueryString["action"]; if (action == "json") JsonRequest(context); else TextRequest(context); } public void TextRequest(HttpContext context) { context.Response.ContentType = "text/plain"; context.Response.Write("Hello World. Time is: " + DateTime.Now.ToString()); } public void JsonRequest(HttpContext context) { var json = JsonConvert.SerializeObject(new Person(), Formatting.None); context.Response.ContentType = "application/json"; context.Response.Write(json); } public bool IsReusable { get { return true; } } } This code adds a little logic to check for a action query string and route the request to an optional JSON result method. To generate JSON, I'm using the same JSON.NET serializer (JsonConvert.SerializeObject) used in Web API to create the JSON response. WCF REST   [ServiceContract(Namespace = "")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class WcfService { [OperationContract] [WebGet] public Stream HelloWorld() { var data = Encoding.Unicode.GetBytes("Hello World " + DateTime.Now.ToString()); var ms = new MemoryStream(data); // Add your operation implementation here return ms; } [OperationContract] [WebGet(ResponseFormat=WebMessageFormat.Json,BodyStyle=WebMessageBodyStyle.WrappedRequest)] public Person HelloWorldJson() { // Add your operation implementation here return new Person(); } } For WCF REST all I have to do is add a method with the Person result type.   ASP.NET MVC public class MvcPerformanceController : Controller { // // GET: /MvcPerformance/ public ActionResult Index() { return View(); } public ActionResult HelloWorldCode() { return new ContentResult() { Content = "Hello World. Time is: " + DateTime.Now.ToString() }; } public JsonResult HelloWorldJson() { return Json(new Person(), JsonRequestBehavior.AllowGet); } } For MVC all I have to do for a JSON response is return a JSON result. ASP.NET internally uses JavaScriptSerializer. ASP.NET WebAPI public class WebApiPerformanceController : ApiController { [HttpGet] public HttpResponseMessage HelloWorldCode() { return new HttpResponseMessage() { Content = new StringContent("Hello World. Time is: " + DateTime.Now.ToString(), Encoding.UTF8, "text/plain") }; } [HttpGet] public Person HelloWorldJson() { return new Person(); } [HttpGet] public HttpResponseMessage HelloWorldJson2() { var response = new HttpResponseMessage(HttpStatusCode.OK); response.Content = new ObjectContent<Person>(new Person(), GlobalConfiguration.Configuration.Formatters.JsonFormatter); return response; } } Testing and Results To run these data requests I used the following ab.exe commands:REM JSON RESPONSES ab.exe -n100000 -c20 http://localhost/aspnetperf/Handler.ashx?action=json > HandlerJson.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldJson > MvcJson.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorldJson > WebApiJson.txt ab.exe -n100000 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorldJson > WcfJson.txt The results from this test run are a bit interesting in that the WebAPI test improved performance significantly over returning plain string content. Here are the results:   The performance for each technology drops a little bit except for WebAPI which is up quite a bit! From this test it appears that WebAPI is actually significantly better performing returning a JSON response, rather than a plain string response. Snag with Apache Benchmark and 'Length Failures' I ran into a little snag with Apache Benchmark, which was reporting failures for my Web API requests when serializing. As the graph shows performance improved significantly from with JSON results from 5580 to 6530 or so which is a 15% improvement (while all others slowed down by 3-8%). However, I was skeptical at first because the WebAPI test reports showed a bunch of errors on about 10% of the requests. Check out this report: Notice the Failed Request count. What the hey? Is WebAPI failing on roughly 10% of requests when sending JSON? Turns out: No it's not! But it took some sleuthing to figure out why it reports these failures. At first I thought that Web API was failing, and so to make sure I re-ran the test with Fiddler attached and runiisning the ab.exe test by using the -X switch: ab.exe -n100 -c10 -X localhost:8888 http://localhost/aspnetperf/api/HelloWorldJson which showed that indeed all requests where returning proper HTTP 200 results with full content. However ab.exe was reporting the errors. After some closer inspection it turned out that the dates varying in size altered the response length in dynamic output. For example: these two results: {"Id":10,"Name":"Rick","Entered":"2012-09-04T10:57:24.841926-10:00"} {"Id":10,"Name":"Rick","Entered":"2012-09-04T10:57:24.8519262-10:00"} are different in length for the number which results in 68 and 69 bytes respectively. The same URL produces different result lengths which is what ab.exe reports. I didn't notice at first bit the same is happening when running the ASHX handler with JSON.NET result since it uses the same serializer that varies the milliseconds. Moral: You can typically ignore Length failures in Apache Benchmark and when in doubt check the actual output with Fiddler. Note that the other failure values are accurate though. Another interesting Side Note: Perf drops over Time As I was running these tests repeatedly I was finding that performance steadily dropped from a startup peak to a 10-15% lower stable level. IOW, with Web API I'd start out with around 6500 req/sec and in subsequent runs it keeps dropping until it would stabalize somewhere around 5900 req/sec occasionally jumping lower. For these tests this is why I did the IIS RESET and warm up for individual tests. This is a little puzzling. Looking at Process Monitor while the test are running memory very quickly levels out as do handles and threads, on the first test run. Subsequent runs everything stays stable, but the performance starts going downwards. This applies to all the technologies - Handlers, Web Forms, MVC, Web API - curious to see if others test this and see similar results. Doing an IISRESET then resets everything and performance starts off at peak again… Summary As I stated at the outset, these were informal to satiate my curiosity not to prove that any technology is better or even faster than another. While there clearly are differences in performance the differences (other than WCF REST which was by far the slowest and the raw handler which was by far the highest) are relatively minor, so there is no need to feel that any one technology is a runaway standout in raw performance. Choosing a technology is about more than pure performance but also about the adequateness for the job and the easy of implementation. The strengths of each technology will make for any minor performance difference we see in these tests. However, to me it's important to get an occasional reality check and compare where new technologies are heading. Often times old stuff that's been optimized and designed for a time of less horse power can utterly blow the doors off newer tech and simple checks like this let you compare. Luckily we're seeing that much of the new stuff performs well even in V1.0 which is great. To me it was very interesting to see Web API perform relatively badly with plain string content, which originally led me to think that Web API might not be properly optimized just yet. For those that caught my Tweets late last week regarding WebAPI's slow responses was with String content which is in fact considerably slower. Luckily where it counts with serialized JSON and XML WebAPI actually performs better. But I do wonder what would make generic string content slower than serialized code? This stresses another point: Don't take a single test as the final gospel and don't extrapolate out from a single set of tests. Certainly Twitter can make you feel like a fool when you post something immediate that hasn't been fleshed out a little more <blush>. Egg on my face. As a result I ended up screwing around with this for a few hours today to compare different scenarios. Well worth the time… I hope you found this useful, if not for the results, maybe for the process of quickly testing a few requests for performance and charting out a comparison. Now onwards with more serious stuff… Resources Source Code on GitHub Apache HTTP Server Project (ab.exe is part of the binary distribution)© Rick Strahl, West Wind Technologies, 2005-2012Posted in ASP.NET  Web Api   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Formal Languages, Inductive Proofs &amp; Regular Expressions

  - by MarkPearl

  So I am slogging away at my UNISA stuff. I have just finished doing the initial once non stop read through the first 11 chapters of my COS 201 Textbook - “Introduction to Computer Theory 2nd Edition” by Daniel Cohen. It has been an interesting couple of days, with familiar concepts coming up as well as some new territory. In this posting I am going to cover the first couple of chapters of the book. Let start with Formal Languages… What exactly is a formal language? Pretty much a no duh question for me but still a good one to ask – a formal language is a language that is defined in a precise mathematical way. Does that mean that the English language is a formal language? I would say no – and my main motivation for this is that one can have an English sentence that is correct grammatically that is also ambiguous. For example the ambiguous sentence: "I once shot an elephant in my pyjamas.” For this and possibly many other reasons that I am unaware of, English is termed a “Natural Language”. So why the importance of formal languages in computer science? Again a no duh question in my mind… If we want computers to be effective and useful tools then we need them to be able to evaluate a series of commands in some form of language that when interpreted by the device no confusion will exist as to what we were requesting. Imagine the mayhem that would exist if a computer misinterpreted a command to print a document and instead decided to delete it. So what is a Formal Language made up of… For my study purposes a language is made up of a finite alphabet. For a formal language to exist there needs to be a specification on the language that will describe whether a string of characters has membership in the language or not. There are two basic ways to do this: By a “machine” that will recognize strings of the language (e.g. Finite Automata). By a rule that describes how strings of a language can be formed (e.g. Regular Expressions). When we use the phrase “string of characters”, we can also be referring to a “word”. What is an Inductive Proof? So I am not to far into my textbook and of course it starts referring to proofs and different types. I have had to go through several different approaches of proofs in the past, but I can never remember their formal names , so when I saw “inductive proof” I thought to myself – what the heck is that? Google to the rescue… An inductive proof is like a normal proof but it employs a neat trick which allows you to prove a statement about an arbitrary number n by first proving it is true when n is 1 and then assuming it is true for n=k and showing it is true for n=k+1. The idea is that if you want to show that someone can climb to the nth floor of a fire escape, you need only show that you can climb the ladder up to the fire escape (n=1) and then show that you know how to climb the stairs from any level of the fire escape (n=k) to the next level (n=k+1). Does this sound like a form of recursion? No surprise then that in the same chapter they deal with recursive definitions. An example of a recursive definition for the language EVEN would the 3 rules below: 2 is in EVEN If x is in EVEN then so is x+2 The only elements in the set EVEN are those that be produced by the rules above. Nothing to exciting… So if a definition for a language is done recursively, then it makes sense that the language can be proved using induction. Regular Expressions So I am wondering to myself what use is this all – in fact – I find this the biggest challenge to any university material is that it is quite hard to find the immediate practical applications of some theory in real life stuff. How great was my joy when I suddenly saw the word regular expression being introduced. I had been introduced to regular expressions on Stack Overflow where I was trying to recognize if some text measurement put in by a user was in a valid form or not. For instance, the imperial system of measurement where you have feet and inches can be represented in so many different ways. I had eventually turned to regular expressions as an easy way to check if my parser could correctly parse the text or not and convert it to a normalize measurement. So some rules about languages and regular expressions… Any finite language can be represented by at least one if not more regular expressions A regular expressions is almost a rule syntax for expressing how regular languages can be formed regular expressions are cool For a regular expression to be valid for a language it must be able to generate all the words in the language and no other words. This is important. It doesn’t help me if my regular expression parses 100% of my measurement texts but also lets one or two invalid texts to pass as well. Okay, so this posting jumps around a bit – but introduces some very basic fundamentals for the subject which will be built on in later postings… Time to go and do some practical examples now…

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• ArcSig Meeting at 04/20/2010 with Sam Abraham

  - by Rainer

  Sam Abraham gave a great presentation, “MVC2 – Do it your way in VS 2010”, at our monthly ArcSig meeting on 04/20/2010 at Global Response. The interest in Sam’s talk was immense, we almost run out of seats. The audience got an in-depth view and walkthrough of the Model View Controller functionality in Visual Studio 2010 with detailed code examples. Sam answered many user questions about practical applications in MVC. Free soft drinks and pizza kept the participants energized during the whole presentation and a raffle of books and software completed this meeting, with a preview about the upcoming meetings and events in May and June. Thank you to Sam for the exciting presentation, and to the Shooster family for hosting us this month at Global Response! Posted: Rainer Habermann ArcSig Site Director CIO @ Global Response

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• Parallelism in .NET – Part 17, Think Continuations, not Callbacks

  - by Reed

  In traditional asynchronous programming, we’d often use a callback to handle notification of a background task’s completion.  The Task class in the Task Parallel Library introduces a cleaner alternative to the traditional callback: continuation tasks. Asynchronous programming methods typically required callback functions.  For example, MSDN’s Asynchronous Delegates Programming Sample shows a class that factorizes a number.  The original method in the example has the following signature: public static bool Factorize(int number, ref int primefactor1, ref int primefactor2) { //... .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } However, calling this is quite “tricky”, even if we modernize the sample to use lambda expressions via C# 3.0.  Normally, we could call this method like so: int primeFactor1 = 0; int primeFactor2 = 0; bool answer = Factorize(10298312, ref primeFactor1, ref primeFactor2); Console.WriteLine("{0}/{1} [Succeeded {2}]", primeFactor1, primeFactor2, answer); If we want to make this operation run in the background, and report to the console via a callback, things get tricker.  First, we need a delegate definition: public delegate bool AsyncFactorCaller( int number, ref int primefactor1, ref int primefactor2); Then we need to use BeginInvoke to run this method asynchronously: int primeFactor1 = 0; int primeFactor2 = 0; AsyncFactorCaller caller = new AsyncFactorCaller(Factorize); caller.BeginInvoke(10298312, ref primeFactor1, ref primeFactor2, result => { int factor1 = 0; int factor2 = 0; bool answer = caller.EndInvoke(ref factor1, ref factor2, result); Console.WriteLine("{0}/{1} [Succeeded {2}]", factor1, factor2, answer); }, null); This works, but is quite difficult to understand from a conceptual standpoint.  To combat this, the framework added the Event-based Asynchronous Pattern, but it isn’t much easier to understand or author. Using .NET 4’s new Task<T> class and a continuation, we can dramatically simplify the implementation of the above code, as well as make it much more understandable.  We do this via the Task.ContinueWith method.  This method will schedule a new Task upon completion of the original task, and provide the original Task (including its Result if it’s a Task<T>) as an argument.  Using Task, we can eliminate the delegate, and rewrite this code like so: var background = Task.Factory.StartNew( () => { int primeFactor1 = 0; int primeFactor2 = 0; bool result = Factorize(10298312, ref primeFactor1, ref primeFactor2); return new { Result = result, Factor1 = primeFactor1, Factor2 = primeFactor2 }; }); background.ContinueWith(task => Console.WriteLine("{0}/{1} [Succeeded {2}]", task.Result.Factor1, task.Result.Factor2, task.Result.Result)); This is much simpler to understand, in my opinion.  Here, we’re explicitly asking to start a new task, then continue the task with a resulting task.  In our case, our method used ref parameters (this was from the MSDN Sample), so there is a little bit of extra boiler plate involved, but the code is at least easy to understand. That being said, this isn’t dramatically shorter when compared with our C# 3 port of the MSDN code above.  However, if we were to extend our requirements a bit, we can start to see more advantages to the Task based approach.  For example, supposed we need to report the results in a user interface control instead of reporting it to the Console.  This would be a common operation, but now, we have to think about marshaling our calls back to the user interface.  This is probably going to require calling Control.Invoke or Dispatcher.Invoke within our callback, forcing us to specify a delegate within the delegate.  The maintainability and ease of understanding drops.  However, just as a standard Task can be created with a TaskScheduler that uses the UI synchronization context, so too can we continue a task with a specific context.  There are Task.ContinueWith method overloads which allow you to provide a TaskScheduler.  This means you can schedule the continuation to run on the UI thread, by simply doing: Task.Factory.StartNew( () => { int primeFactor1 = 0; int primeFactor2 = 0; bool result = Factorize(10298312, ref primeFactor1, ref primeFactor2); return new { Result = result, Factor1 = primeFactor1, Factor2 = primeFactor2 }; }).ContinueWith(task => textBox1.Text = string.Format("{0}/{1} [Succeeded {2}]", task.Result.Factor1, task.Result.Factor2, task.Result.Result), TaskScheduler.FromCurrentSynchronizationContext()); This is far more understandable than the alternative.  By using Task.ContinueWith in conjunction with TaskScheduler.FromCurrentSynchronizationContext(), we get a simple way to push any work onto a background thread, and update the user interface on the proper UI thread.  This technique works with Windows Presentation Foundation as well as Windows Forms, with no change in methodology.

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• What command do I need to unzip/extract a .tar.gz file?

  - by EmmyS

  I received a huge .tar.gz file from a client that contains about 800 mb of image files (when uncompressed.) Our hosting company's ftp is seriously slow, so extracting all the files locally and sending them up via ftp isn't practical. I was able to ftp the .tar.gz file to our hosting site, but when I ssh into my directory and try using unzip, it gives me this error: [esthers@clients locations]$ unzip community_images.tar.gz Archive: community_images.tar.gz End-of-central-directory signature not found. Either this file is not a zipfile, or it constitutes one disk of a multi-part archive. In the latter case the central directory and zipfile comment will be found on the last disk(s) of this archive. note: community_images.tar.gz may be a plain executable, not an archive unzip: cannot find zipfile directory in one of community_images.tar.gz or community_images.tar.gz.zip, and cannot find community_images.tar.gz.ZIP, period. What command do I need to use to extract all the files in a .tar.gz file?

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• How would you advocate not using a shared spreadsheet to track bugs / issues ?

  - by Sylvain Defresne

  In our company, the developers want to use a proper bug tracking tool to manager issues in our application. The management however insists on using a shared spreadsheet (formeerly a shared excel file, now a spreadsheet on a web base solution allowing concurrent access). Their argument is that the spreadsheet allow them to have a more highlevel view of the state of the project as they can see how many bugs are open with a quick glance. This also allow them to see who is working on each bug, and get estimation of the time required to close them all (as developer are required to fill time estimation of the bug they are working on). As you can understand, this is not really practical to use for the developers (bug tracking software were invented for a reason). So how can I advocate bug tracking software to ease the work of the developer ? As a bonus, which software would you recommend that would allow the management to be able to get their feedbacks (number of bugs opens, who is working on them, time estimation) with a high level view ?

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• Google I/O 2010 - Creating positive user experiences

  Google I/O 2010 - Creating positive user experiences Google I/O 2010 - Beyond design: Creating positive user experiences Tech Talks John Zeratsky, Matt Shobe Good user experience isn't just about good design. Learn how to create a positive user experience by being fast, open, engaged, surprising, polite, and, well... being yourself. Chock full of examples from the web and beyond, this talk is a practical introduction for developers who are passionate about user experience but may not have a background in design. For all I/O 2010 sessions, please go to code.google.com From: GoogleDevelopers Views: 185 6 ratings Time: 52:11 More in Science & Technology

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