Search Results

Search found 11672 results on 467 pages for 'formal methods'.

Page 246/467 | < Previous Page | 242 243 244 245 246 247 248 249 250 251 252 253  | Next Page >

• O'Reilly deals to April 5, 2012 14:00 PT on books on "where"

  - by TATWORTH

  At http://shop.oreilly.com/category/deals/where-conference.do, O'Reilly are offering a series of books on geo-location at 50% off until April 5, 2012 14:00 PT. HTML5 Geolocation Truly revolutionary: now you can write geolocation applications directly in the browser, rather than develop native apps for particular devices. This concise book demonstrates the W3C Geolocation API in action, with code and examples to help you build HTML5 apps using the "write once, deploy everywhere" model. Along the way, you get a crash course in geolocation, browser support, and ways to integrate the API with common geo tools like Google Maps. HTML5 Cookbook With scores of practical recipes you can use in your projects right away, this cookbook helps you gain hands-on experience with HTML5’s versatile collection of elements. You get clear solutions for handling issues with everything from markup semantics, web forms, and audio and video elements to related technologies such as geolocation and rich JavaScript APIs. Each informative recipe includes sample code and a detailed discussion on why and how the solution works. Perfect for intermediate to advanced web and mobile web developers, this handy book lets you choose the HTML5 features that work for you—and helps you experiment with the rest. HTML5 Applications HTML5 is not just a replacement for plugins. It also makes the Web a first-class development environment by giving JavaScript programmers a solid foundation for building industrial-strength applications. This practical guide takes you beyond simple site creation and shows you how to build self-contained HTML5 applications that can run on mobile devices and compete with desktop apps. You’ll learn powerful JavaScript tools for exploiting HTML5 elements, and discover new methods for working with data, such as offline storage and multi-threaded processing. Complete with code samples, this book is ideal for experienced JavaScript and mobile developers alike. There are also other books being offered at a discount at http://shop.oreilly.com/category/deals/where-conference.do

  Read the article

• Procurement: Troubleshooting Approval Hierarchy Issues

  - by Annemarie Provisero

  ADVISOR WEBCAST: Procurement: Troubleshooting Approval Hierarchy Issues PRODUCT FAMILY: EBS - Procurement November 29, 2011 at 7 am MST, 9 am EST, 2 pm London, 4 pm Cairo This one-hour session is recommended for technical and functional users who would like to know how Purchasing builds the approval list for a document. It also includes a troubleshooting section for cases where the list does not include the correct approvers or when workflow fails to build the approval list (no approver found). TOPICS WILL INCLUDE: Overview of Oracle Purchasing Approval Hierarchy, The Approval Methods. The Approval List. How to Troubleshoot and Diagnose Related Issues Demonstration A short, live demonstration (only if applicable) and question and answer period will be included. Oracle Advisor Webcasts are dedicated to building your awareness around our products and services. This session does not replace offerings from Oracle Global Support Services. Click here to register for this session ------------------------------------------------------------------------------------------------------------- The above webcast is a service of the E-Business Suite Communities in My Oracle Support. For more information on other webcasts, please reference the Oracle Advisor Webcast Schedule.Click here to visit the E-Business Communities in My Oracle Support Note that all links require access to My Oracle Support.

  Read the article

• Design for object with optional and modifiable attributtes?

  - by Ikuzen

  I've been using the Builder pattern to create objects with a large number of attributes, where most of them are optional. But up until now, I've defined them as final, as recommended by Joshua Block and other authors, and haven't needed to change their values. I am wondering what should I do though if I need a class with a substantial number of optional but non-final (mutable) attributes? My Builder pattern code looks like this: public class Example { //All possible parameters (optional or not) private final int param1; private final int param2; //Builder class public static class Builder { private final int param1; //Required parameters private int param2 = 0; //Optional parameters - initialized to default //Builder constructor public Builder (int param1) { this.param1 = param1; } //Setter-like methods for optional parameters public Builder param2(int value) { param2 = value; return this; } //build() method public Example build() { return new Example(this); } } //Private constructor private Example(Builder builder) { param1 = builder.param1; param2 = builder.param2; } } Can I just remove the final keyword from the declaration to be able to access the attributes externally (through normal setters, for example)? Or is there a creational pattern that allows optional but non-final attributes that would be better suited in this case?

  Read the article

• Custom inventory items based on inheritance

  - by Bogdan Marginean

  So, here's the scenario: I'm building an RPG. Like most of the other RPGs on the market, my game will feature an inventory and of course, inventory items. So far I've worked well with using a single class for all items, because I did not need anything else than character stat alteration on item usage (consumption). However, I'd like some items to have a more exotic effect. Think of something like when the user consumes a transformation potion, he automatically turns into a beast. In order to achieve this I've thought about declaring a new class that inherits from BaseItem for each item. Each descendant would override some methods (like void OnConsume()), to change the base behavior. This works fine, but when it comes to inventory management, I have some issues. The actual inventory will have to work with BaseItem components only (for obvious reasons, as it's an enumerable collection of objects of the same type); casting any descendant to the base class is possible, so no problems in adding items to the inventory. But how can I keep track of the descendant's type (class) for each item in the inventory? And how to perform the descendant's OnConsume from withint he inventory, for each item? Let me know if you can think of a better solution than mine, or if you can think of a solution to my problem only. Development is done in C#, inside Unity 3.5. Thanks!

  Read the article

• Book Review: Professional ASP.Net MVC4

  - by Sam Abraham

  The past few weeks have been particularly busy as I continue to dedicate a bigger portion of my free time to refreshing my memory and enhancing my knowledge of best practices pertaining to technologies we plan on using for a major upcoming project. In this blog post, I will be providing a brief overview of my latest reading “Professional ASP.Net MVC4” by Jon Galloway, Phil Haack, Brad Wilson and K. Scott Allen. This book is a must read for web developers looking to enhance their MVC expertise with best practices and tips shared from recognized industry experts. This book takes the reader on a 16-chapter long journey towards being a better ASP.NET MVC developer with chapter 16 putting all information covered in practical context by dissecting the implementation of Nuget.org, a real-life open-source, ASP.NET MVC project.  All code samples referenced in this book are conveniently accessible via NuGet, a free, open-source Library package manager that installs as a Visual Studio Extension. Chapters 2, 3 and 4 thoroughly cover MVC’s various components: Controllers “C”, Views “V” and Models “M” respectively. Chapter 5 covers additional extension methods (Helpers) provided to speed and ease the use of common HTML elements such as forms, textboxes, grids, to name a few… Chapter 6 tackles built-in validation while providing examples and use cases on implementing custom validation that plugs into the MVC framework. Chapters 7 thru 13 discusses the latest on Membership, Ajax, Routing, NuGet and the ASP.Net Web API. Chapters 12 (Dependency Injection) and 13 (Unit Testing) demonstrate a big competitive advantage of MVC with its ease of test-ability and plug-ability. Chapters 14 and 15 targets the advanced developer showcasing how to extend MVC to customize and replace every piece in the framework.In conclusion, I strongly recommend Professional ASP.NET MVC 4 as an excellent read for both developers already using MVC as well as those getting started with the framework.   Many thanks to the Wiley/Wrox User Group Program for their support of our West Palm Beach Developers’ Group.  You can access my reviews of books I recently read: Professional ASP.NET Design Patterns Professional WCF 4.0 Inside Windows Communication Foundation Inside Microsoft SQL Server 2008 series

  Read the article

• AsyncBridge? Async on .NET 4.0 using VS11

  - by Alex.Davies

  I've just found something quite cool. It's a code snippet that lets you use the real VS 11 C#5 compiler to write code that uses the async and await keywords, but to target .NET 4.0. It was published by Daniel Grunwald (from SharpDevelop).That means I can stop using the Async CTP for VS2010, which is not at all supported anymore, and a pain to install if you have windows updates turned on. Obviously I couldn't ask all my users to install .NET 4.5 beta, but .NET Demon is a VS 2010 extension, so we already have .NET 4.0. At the time of writing, VS11 is in beta still, but hopefully it's stable enough for my team to use!I would have written the code myself, but I had the wrong impression that the C# 5 beta compiler only looked in mscorlib for the helper classes it needs to implement async methods. Turns out you can provide them yourself. You can get the code here: https://gist.github.com/1961087You just add it to your project, and the compiler will apparently pick it up and use it to implement async/await. I'm at my parents' place for Easter without access to a machine with VS 11 to try it out. Let me know whether you get it to work!This reminds me of LINQBridge, which let us use C# 3 LINQ, but only require .NET 2. We should stick up a webpage to explain, with a nice easy dll, put it in nuget, and call it AsyncBridge.If you were really enthusiastic, you could re-implement the skeleton of the Task Parallel Library against .NET 2 to use async/await without even requiring .NET 4. Our usage stats suggest that practically everyone that uses Red Gate tools already has .NET 4 installed though, so I don't think I'll go to the effort.

  Read the article

• Which Graphics/Geometry abstraction to choose?

  - by Robz

  I've been thinking about the design for a browser app on the HTML5 canvas that simulates a 2D robot zooming around, sensing the world around it. I decided to do this from scratch just for fun. I need shapes, like polygons, circles, and lines in order to model the robot and the world it lives in. These shapes need to be drawn with different appearance attributes, like border/fill style/width/color. I also need to have geometry functions to detect intersections and containment for the robot's sensors and so that the robot doesn't go inside stuff. One idea for functions is to have two totally separate libraries, one to implement graphics (like drawShape(context, shape)) and one for geometry operations (like shapeIntersectsShape(shape1, shape2)). Or, in a more object-oriented approach, the shape objects themselves could implement methods to do their own graphics (shape.draw(context)) and geometry operations (shape1.intersects(shape2)). Then there is the data itself: whether the data to draw a shape and the data to do geometric operations on that shape should be encapsulated within the same object, or be separate structures (where one would contain the other, or both be contained inside another structure). How do existing applications that do graphics/geometry stuff deal with this? Is there one model that is best, or is each good for certain applications? Should the fact that I'm using Javascript instead of a more classical language change how I approach the design?

  Read the article

• How would you TDD the functionality of getting the corresponding process of a running windows service?

  - by Matt Spinelli

  Purpose Over the last year or more I've been learning unit testing via books I've read recently like The Art of Unit Testing, Working Effectively with Legacy Code, and others. I've also been using unit tests, mocking frameworks, and the like, periodically at work and definitely see the value. However, I'm still having a hard time wrapping my mind around TDD (as opposed to TAD) when the situation calls for code that is gong to mostly use external API calls. Problem to solve Get the process associated with a windows service using the service name. example: Function GetProcess(ByVal serviceName As String) As Process Rules Show each major iteration in production & test code using TDD No need to see any other code or configuration that is required to get things to run. Just curious about the interfaces, concrete classes, and test methods. C# or VB.NET Must use the .Net framework regarding services/processes (i.e. System.Diagnostics.Process) Test Frameworks: Nunit or MSTest Isolation Frameworks: Moq, Rhino Mock, or Microsoft Moles Must write true unit tests (no integration tests) Additional notes As far as I can tell there are two approaches design wise. Use an Inversion of Control approach along with using the Adapter and/or Facade patterns to wrap the underlying .net framework objects dealing with processes and services. Keep the .net framework code in the class containing the Get Process method and use code detouring (interception) via Microsoft Moles to isolate the hard dependencies from the method under test.

  Read the article

• Have you used nDepend?

  - by Nick Harrison

  Have you Used NDepend? I have often wanted to use it, but never spent the money on it.   I have developed many tools that try to do pieces of what NDepend does, but never with as much success as they reach. Put simply, it is a tool that will allow you to udnerstand and monitor the architecture of your software, and it does it in some pretty amazing ways. One of the most impressive features is something that they call Code Query Language.   It allows you to write queries very similar to SQL to track the performance of various software metrics and use this to identify areas that are out of compliance with your standards and architecture. For instance, once you have analyzed your project, you can write queries such as : SELECT METHODS WHERE IsPublic AND CouldBePrivate  You can also set up such queries to provide warnings if there are records returned.    You can incorporae this into your daily build and compare build against build. There are over 82 metrics included to allow you to view your code in a variety of angles. I have often advocated for a "Code Inventory" database to track the state of software and the ROI on software investments.    This tool alone will take you about 90% of the way there. If you are not using it yet,  I strongly recommend that you do!

  Read the article

• Using 12.04 installation as a persistent pen drive

  - by Cawas

  Disclaimer: I aim to build a self contained pen drive with my application inside, so no matter about updates. Maybe I'm looking at the wrong linux distribution to do this... Please let me know if you think so. I've tried knoppix and even lubuntu, but they don't come with enough "drivers" for Unity3D to work. Creating a custom live persistent pen drive is a real pain and I'm trying for 1 day without any success. Sure, being able to do it would probably be ideal and occupy the minimum space. Using the installation image on a pen drive, however, is good enough and is really easy to create. We can even do it from any OS, using UNetBootin, LiLi USB Creator or some other methods. Straight forward. Some recommend installing it on a pen drive. But that requires a lot of space and, I believe, it won't behave as good as something meant to be installed on a usb disk, because of memory management. So, there are only a few negative points on using the installation image that I can think of. Question here, is how to remove those drawbacks: Having to press "Try Ubuntu". That's the big one. Couldn't find how. Unable to load everything on memory and keep on running without the pen drive (like this) Unable to remove "Install Ubuntu 12.04 LTS" app. Setting the ISO to use maximum amount of space for the OS will leave pen drive with zero space left and any file saved within it from ubuntu is inaccessible from the outside (when plugin the pen drive and not booting from it). Am I missing something? Can those points be fixed?

  Read the article

• Augmenting functionality of subclasses without code duplication in C++

  - by Rob W

  I have to add common functionality to some classes that share the same superclass, preferably without bloating the superclass. The simplified inheritance chain looks like this: Element -> HTMLElement -> HTMLAnchorElement Element -> SVGElement -> SVGAlement The default doSomething() method on Element is no-op by default, but there are some subclasses that need an actual implementation that requires some extra overridden methods and instance members. I cannot put a full implementation of doSomething() in Element because 1) it is only relevant for some of the subclasses, 2) its implementation has a performance impact and 3) it depends on a method that could be overridden by a class in the inheritance chain between the superclass and a subclass, e.g. SVGElement in my example. Especially because of the third point, I wanted to solve the problem using a template class, as follows (it is a kind of decorator for classes): struct Element { virtual void doSomething() {} }; // T should be an instance of Element template<class T> struct AugmentedElement : public T { // doSomething is expensive and uses T virtual void doSomething() override {} // Used by doSomething virtual bool shouldDoSomething() = 0; }; class SVGElement : public Element { /* ... */ }; class SVGAElement : public AugmentedElement<SVGElement> { // some non-trivial check bool shouldDoSomething() { /* ... */ return true; } }; // Similarly for HTMLAElement and others I looked around (in the existing (huge) codebase and on the internet), but didn't find any similar code snippets, let alone an evaluation of the effectiveness and pitfalls of this approach. Is my design the right way to go, or is there a better way to add common functionality to some subclasses of a given superclass?

  Read the article

• For a Javascript library, what is the best or standard way to support extensibility

  - by Michael Best

  Specifically, I want to support "plugins" that modify the behavior of parts of the library. I couldn't find much information on the web about this subject. But here are my ideas for how a library could be extensible. The library exports an object with both public and "protected" functions. A plugin can replace any of those functions, thus modifying the library's behavior. Advantages of this method are that it's simple and that the plugin's functions can have full access to the library's "protected" functions. Disadvantages are that the library may be harder to maintain with a larger set of exposed functions and it could be hard to debug if multiple plugins are involved (how to know which plugin modified which function?). The library provides an "add plugin" function that accepts an object with a specific interface. Internally, the library will use the plugin instead of it's own code if appropriate. With this method, the internals of the library can be rearranged more freely as long as it still supports the same plugin interface. This could also support having different plugin interfaces to modify different parts of the library. A disadvantage of this method is that the plugins may have to re-implement code that is already part of the library since the library's internal functions are not exported. The library provides a "set implementation" function that accepts an object inherited from a specific base object. The library's public API calls functions in the implementation object for any functionality that can be modified and the base implementation object includes the core functionality, with both external (to the API) and internal functions. A plugin creates a new implementation object, which inherits from the base object and replaces any functions it wants to modify. This combines advantages and disadvantages of both the other methods.

  Read the article

• Control convention for circular movement?

  - by Christian

  I'm currently doing a kind of training project in Unity (still a beginner). It's supposed to be somewhat like Breakout, but instead of just going left and right I want the paddle to circle around the center point. This is all fine and dandy, but the problem I have is: how do you control this with a keyboard or gamepad? For touch and mouse control I could work around the problem by letting the paddle follow the cursor/finger, but with the other control methods I'm a bit stumped. With a keyboard for example, I could either make it so that the Left arrow always moves the paddle clockwise (it starts at the bottom of the circle), or I could link it to the actual direction - meaning that if the paddle is at the bottom, it goes left and up along the circle or, if it's in the upper hemisphere, it moves left and down, both times toward the outer left point of the circle. Both feel kind of weird. With the first one, it can be counter intuitive to press Left to move the paddle right when it's in the upper area, while in the second method you'd need to constantly switch buttons to keep moving. So, long story short: is there any kind of existing standard, convention or accepted example for this type of movement and the corresponding controls? I didn't really know what to google for (control conventions for circular movement was one of the searches I tried, but it didn't give me much), and I also didn't really find anything about this on here. If there is a Question that I simply didn't see, please excuse the duplicate.

  Read the article

• New features for Expression Blend 4 Release Candidate

  - by kaleidoscope

  With Microsoft Expression Blend 4, you can create websites and applications based on Microsoft Silverlight 3 and Microsoft Silverlight 4, and desktop applications based on Windows Presentation Foundation (WPF) 3.5 with Service Pack 1 (SP1) and WPF4. Expression Blend provides new support for prototyping, interactivity through behaviors, special Silverlight functionality, and on-the-fly sample data generation. Expression Blend includes new behaviors that are quickly and easily configured Expression Blend offers new sample data, behaviors, and features of project templates to support the Model-View-ViewModel (MVVM) pattern The MVVM pattern is a way to structure a Silverlight or WPF application so that user interface (UI) objects are as decoupled as possible from the application's data and behavior. This makes it easier for design tasks and development tasks to be performed independently and without breaking each other. Essentially, your UI is the View. You bind objects in the View to properties and commands of the ViewModel, and the View can also call methods on the ViewModel. Compatible with Silverlight 3 and WPF 3.5 with Service Pack 1 (SP1) Interoperate able with Visual Studio. Included New Shapes: The Assets panel in Expression Blend contains a new Shapes category, including presets for the easy creation of arcs, arrows, callouts, and polygons. New Controls: Expression Blend has tooling support for the RichTextBox control in Silverlight. XAML cleanliness :Expression Blend generates less XAML with respect to animations and animation-related properties. MVVM project template: Expression Blend includes a new project template that offers a basic starting point for Model-View-ViewModel pattern applications. Run project with CTRL+F5:To improve consistency with Visual Studio, you can now invoke the Run Project command by pressing either CTRL+F5 or F5 Technorati Tags: Rituraj,Features of Expression Blend4 RC

  Read the article

• Thinking skills to be a good programmer

  - by Paul

  I have been programming for last 15 years with non-CS degree. Main reason I got into programming was that I liked to learn new things and apply them to my work. And I was able to find and fix programming errors and their causes faster than others. But I never find myself a a guru or an expert, maybe due to my non-CS major. And when I saw great programmers, I observed they are very good, much better than me of course, at solving problems. One skill I found good in my mid-career is thinking of requirements and tasks in a reverse order and in abstract. In that way, I can see what is really required for me to do without detail and can quickly find parts of solution that already exist. So I wonder if there are other thinking skills to be a good programmer. I've followed Q&As below and actually read some of books recommended there. But I couldn't really pickup good methods directly applicable for my programming work. What non-programming books should a programmer read to help develop programming/thinking skills? Skills and habits to develop to be good at programming (I'm a newbie)

  Read the article

• Announcing Oracle Receivables Generic Data Fix (GDF) for Refunds

  - by user793553

  Here's the first of what will be a series of Generic Data Fixes (GDF) to be released by Receivables Development. Generic Data Fix (GDF) are created by development to fix data issues caused by bugs/issues in the application code.  Other Generic Data Fix benefits/features include: Developed for bugs that can cause data issues. Provides a SELECT script that uses an identification/signature query to identify and report all data affected by issue/condition caused by a bug. Allow customers to view and modify what will be fixed. Provides a separate FIX script to fix the data reported by the SELECT script. The FIX script creates backup tables for the data that is fixed/updated. Available on My Oracle Support for download In Release 12, when creating a refund by either of the following methods: Applied a receipt to the Refund activity - which creates an Invoice in Payables Or you went directly into Payables to create a refund for an open Credit Memo in Receivables The Invoice in Payables that is associated to the refund is cancelled, the corresponding refund application or credit memo in Receivables is not properly re-instated. For the receipt application, it still remains applied to the Refund whereas this should be automatically unapplied. For the credit memo, it stays closed instead of getting re-opened. Doc ID 761993.1 includes the patch to make sure this doesn’t happen in the future as well as a GDF script to fix the current data (Script name: ar_std_refund_unapp.sql).  Download the script and run in READ_ONLY_MODE to identify 'refund' applications with this problem. Stay tuned for more GDF scripts coming soon...

  Read the article

• Lifecycle of an ASP.NET MVC 5 Application

  Here you can download a PDF Document that charts the lifecycle of every ASP.NET MVC 5 application, from receiving the HTTP request to sending the HTTP response back to the client. It is designed both as an educational tool for those who are new to ASP.NET MVC and also as a reference for those who need to drill into specific aspects of the application. The PDF document has the following features: Relevant HttpApplication stages to help you understand where MVC integrates into the ASP.NET application lifecycle. A high-level view of the MVC application lifecycle, where you can understand the major stages that every MVC application passes through in the request processing pipeline. A detail view that shows drills down into the details of the request processing pipeline. You can compare the high-level view and the detail view to see how the lifecycles details are collected into the various stages. Placement and purpose of all overridable methods on the Controller object in the request processing pipeline. You may or may not have the need to override any one method, but it is important for you to understand their role in the application lifecycle so that you can write code at the appropriate life cycle stage for the effect you intend. Blown-up diagrams showing how each of the filter types (authentication, authorization, action, and result) is invoked. Link to a useful article or blog from each point of interest in the detail view. span.fullpost {display:none;}

  Read the article

• Methodologies for Managing Users and Access?

  - by MadBurn

  This is something I'm having a hard time getting my head around. I think I might be making it more complicated than it is. What I'm trying to do is develop a method to store users in a database with varying levels of access, throughout different applications. I know this has been done before, but I don't know where to find how they did it. Here is an example of what I need to accomplish: UserA - Access to App1, App3, App4 & can add new users to App3, but not 4 or 1. UserB - Access to App2 only with ReadOnly access. UserC - Access to App1 & App4 and is able to access Admin settings of both apps. In the past I've just used user groups. However, I'm reaching a phase where I need a bit more control over each individual user's access to certain parts of the different applications. I wish this were as cut and dry as being able to give a user a role and let each role inherit from the last. Now, this is what I need to accomplish. But, I don't know any methods of doing this. I could easily just design something that works, but I know this has been done and I know this has been studied and I know this problem has been solved by much better minds than my own. This is for a web application and using sql server 2008. I don't need to store passwords (LDAP) and the information I need to store is actually very limited. Basically just username and access.

  Read the article

• Inspiring the method of teaching. Example- C++ :)

  - by Ashwin

  A year ago I graduated with a degree in Computer Science and Engineering. Considering C++ as the first choice of programming language I have been in the process of learning C++ in many ways. At first - five years back - I had many conceptions, most of which were so abstract to me. It started when I knew almost everything about Structs in C and nothing about Classes in C++. I went through a great time experimenting them all and learning a lot. I had a hard time evaluating Procedural programming vs Object-Oriented Programming. Deciding when to choose Procedural or Object-Oriented Programming took a great deal of patience for me. I knew that I cannot underestimate any of these Programming styles... Though Procedural programming is often a better choice than simple sequential unstructured programming, when solving problems with procedural programming, we usually divide one problem into several steps in order regarded as functions. Then we call these functions one by one to get the result of the problem. When solving problems with Object Oriented Priciples we divide one problem into several classes and form the interaction between them. Evaluating these two at the beginning (as a learner) required a lot of inspiration and thoughts. Instructing to think step by step. Relative concepts to understand deeply. Intensive interests to contrast both solving in both POP and OOP. If you were ever a mentor: What ideas/methods would you teach to students in which it will Inspire them to learn a programming language (in general, computer sciences)?

  Read the article

• which style of member-access is preferable

  - by itwasntpete

  the purpose of oop using classes is to encapsulate members from the outer space. i always read that accessing members should be done by methods. for example: template<typename T> class foo_1 { T state_; public: // following below }; the most common doing that by my professor was to have a get and set method. // variant 1 T const& getState() { return state_; } void setState(T const& v) { state_ = v; } or like this: // variant 2 // in my opinion it is easier to read T const& state() { return state_; } void state(T const& v) { state_ = v; } assume the state_ is a variable, which is checked periodically and there is no need to ensure the value (state) is consistent. Is there any disadvantage of accessing the state by reference? for example: // variant 3 // do it by reference T& state() { return state_; } or even directly, if I declare the variable as public. template<typename T> class foo { public: // variant 4 T state; }; In variant 4 I could even ensure consistence by using c++11 atomic. So my question is, which one should I prefer?, Is there any coding standard which would decline one of these pattern? for some code see here

  Read the article

• Is implementing an interface defined in a subpackage an anti-pattern?

  - by Michael Kjörling

  Let's say I have the following: package me.my.pkg; public interface Something { /* ... couple of methods go here ... */ } and: package me.my; import me.my.pkg.Something; public class SomeClass implements Something { /* ... implementation of Something goes here ... */ /* ... some more method implementations go here too ... */ } That is, the class implementing an interface lives closer to the package hierarchy root than does the interface it implements but they both belong in the same package hierarchy. The reason for this in the particular case I have in mind is that there is a previously-existing package that groups functionality which the Something interface logically belongs to, and the logical (as in both "the one you'd expect" and "the one where it needs to go given the current architecture") implementation class exists previously and lives one level "up" from the logical placement of the interface. The implementing class does not logically belong anywhere under me.my.pkg. In my particular case, the class in question implements several interfaces, but that feels like it doesn't make any (or at least no significant) difference here. I can't decide if this is an acceptable pattern or not. Is it or is it not, and why?

  Read the article

• What functionality should a (basic) mock framework have?

  - by user1175327

  If i would start on writing a simple Mock framework, then what are the things that a basic mock framework MUST have? Obviously mocking any object, but what about assertions and perhaps other things? When I think of how I would write my own mock framework then I realise how much I really know (or don't know) and what I would trip up on. So this is more for educational purposes. Of course I did research and this is what i've come up with that a minimal mocking framework should be able to do. Now my question in this whole thing is, am I missing some important details in my ideas? Mocking Mocking a class: Should be able to mock any class. The Mock should preserve the properties and their original values as they were set in the original class. All method implementations are empty. Calls to methods of Mock: The Mock framework must be able to define what a mocked method must return. IE: $MockObj->CallTo('SomeMethod')->Returns('some value'); Assertions To my understanding mocking frameworks also have a set of assertions. These are the ones I think are most important (taken from SimpleTest). expect($method, $args) Arguments must match if called expectAt($timing, $method, $args) Arguments must match when called on the $timing'th time expectCallCount($method, $count) The method must be called exactly this many times expectMaximumCallCount($method, $count) Call this method no more than $count times expectMinimumCallCount($method, $count) Must be called at least $count times expectNever($method) Must never be called expectOnce($method, $args) Must be called once and with the expected arguments if supplied expectAtLeastOnce($method, $args) Must be called at least once, and always with any expected arguments And that's basically, as far as I understand, what a mock framework should be able to do. But is this really everything? Because it currently doesn't seem like a big deal to build something like this. But that's also the reason why I have the feeling that i'm missing some important details about such a framework. So is my understanding right about a mock framework? Or am i missing alot of details?

  Read the article

• Parallel Class/Interface Hierarchy with the Facade Design Pattern?

  - by Mike G

  About a third of my code is wrapped inside a Facade class. Note that this isn't a "God" class, but actually represents a single thing (called a Line). Naturally, it delegates responsibilities to the subsystem behind it. What ends up happening is that two of the subsystem classes (Output and Timeline) have all of their methods duplicated in the Line class, which effectively makes Line both an Output and a Timeline. It seems to make sense to make Output and Timeline interfaces, so that the Line class can implement them both. At the same time, I'm worried about creating parallel class and interface structures. You see, there are different types of lines AudioLine, VideoLine, which all use the same type of Timeline, but different types of Output (AudioOutput and VideoOutput, respectively). So that would mean that I'd have to create an AudioOutputInterface and VideoOutputInterface as well. So not only would I have to have parallel class hierarchy, but there would be a parallel interface hierarchy as well. Is there any solution to this design flaw? Here's an image of the basic structure (minus the Timeline class, though know that each Line has-a Timeline): NOTE: I just realized that the word 'line' in Timeline might make is sound like is does a similar function as the Line class. They don't, just to clarify.

  Read the article

• Mocking concrete class - Not recommended

  - by Mik378

  I've just read an excerpt of "Growing Object-Oriented Software" book which explains some reasons why mocking concrete class is not recommended. Here some sample code of a unit-test for the MusicCentre class: public class MusicCentreTest { @Test public void startsCdPlayerAtTimeRequested() { final MutableTime scheduledTime = new MutableTime(); CdPlayer player = new CdPlayer() { @Override public void scheduleToStartAt(Time startTime) { scheduledTime.set(startTime); } } MusicCentre centre = new MusicCentre(player); centre.startMediaAt(LATER); assertEquals(LATER, scheduledTime.get()); } } And his first explanation: The problem with this approach is that it leaves the relationship between the objects implicit. I hope we've made clear by now that the intention of Test-Driven Development with Mock Objects is to discover relationships between objects. If I subclass, there's nothing in the domain code to make such a relationship visible, just methods on an object. This makes it harder to see if the service that supports this relationship might be relevant elsewhere and I'll have to do the analysis again next time I work with the class. I can't figure out exactly what he means when he says: This makes it harder to see if the service that supports this relationship might be relevant elsewhere and I'll have to do the analysis again next time I work with the class. I understand that the service corresponds to MusicCentre's method called startMediaAt. What does he mean by "elsewhere"? The complete excerpt is here: http://www.mockobjects.com/2007/04/test-smell-mocking-concrete-classes.html

  Read the article

• How to avoid game objects accidentally deleting themselves in C++

  - by Tom Dalling

  Let's say my game has a monster that can kamikaze explode on the player. Let's pick a name for this monster at random: a Creeper. So, the Creeper class has a method that looks something like this: void Creeper::kamikaze() { EventSystem::postEvent(ENTITY_DEATH, this); Explosion* e = new Explosion; e->setLocation(this->location()); this->world->addEntity(e); } The events are not queued, they get dispatched immediately. This causes the Creeper object to get deleted somewhere inside the call to postEvent. Something like this: void World::handleEvent(int type, void* context) { if(type == ENTITY_DEATH){ Entity* ent = dynamic_cast<Entity*>(context); removeEntity(ent); delete ent; } } Because the Creeper object gets deleted while the kamikaze method is still running, it will crash when it tries to access this->location(). One solution is to queue the events into a buffer and dispatch them later. Is that the common solution in C++ games? It feels like a bit of a hack, but that might just be because of my experience with other languages with different memory management practices. In C++, is there a better general solution to this problem where an object accidentally deletes itself from inside one of its methods?

  Read the article

< Previous Page | 242 243 244 245 246 247 248 249 250 251 252 253  | Next Page >