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• iTunes command+tab does not bring main window the foreground after command+h

  - by ecoffey

  Related to : Cmd-Tab does not bring iTunes to foreground There people claim that command+h will continue to work, but the behavior I'm seeing is: Launch a full screen Terminal instance (or anything else really) Launch a fresh iTunes command+h to hide it command+tab back to iTunes, this works and the main app window is given focus command+tab to Terminal command+tab to iTunes What I expect to happen: the main iTunes window is brought to the foreground and given focus. What does happen: The application menu bar shows iTunes, but an additional command+` is needed to bring the main app to foreground. I thought it might have been related to a Chrome interaction, since I'm usually commmand+tabbing between my browser and everything else, but that does not seem to be the case. I do have two "plugins" running: last.fm scrobbler Alfred app mini itunes player interface Not sure if either of those create some phantom window or something that is mixing something up. Versions of stuff: OS X: 10.6.5 iTunes: 10.1.1 (4) last.fm: can't find it, but it's recent Alfred: 0.8 (89) So after that big long rant, anyone else seeing this behavior?

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• How reliable is HDD SMART data?

  - by andahlst

  Based on SMART data, you can judge the health of a disk, at least that is the idea. If I, for instance, run sudo smartctl -H /dev/sda on my ArchLinux laptop, it says that the hard drive passed the self tests and that it should be "healthy" based on this. My question is how reliable this information is, or more specifically: If according to the SMART data this disk is healthy, what are the odds of the disk suddenly failing despite this? This assumes the failure is not due to some catastrophic event that impossibly could have been predicted, such as the laptop falling down on the floor causing the drive heads to hit the disk. If the SMART data does not say the disk is in good shape, what are the odds of the disk failing within some amount of time? Is it possible that there will be false positives and how common are these? Of course, I keep backups no matter what. I am mostly curious.

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• Variant Management– Which Approach fits for my Product?

  - by C. Chadwick

  Jürgen Kunz – Director Product Development – Oracle ORACLE Deutschland B.V. & Co. KG Introduction In a difficult economic environment, it is important for companies to understand the customer requirements in detail and to address them in their products. Customer specific products, however, usually cause increased costs. Variant management helps to find the best combination of standard components and custom components which balances customer’s product requirements and product costs. Depending on the type of product, different approaches to variant management will be applied. For example the automotive product “car” or electronic/high-tech products like a “computer”, with a pre-defined set of options to be combined in the individual configuration (so called “Assembled to Order” products), require a different approach to products in heavy machinery, which are (at least partially) engineered in a customer specific way (so-called “Engineered-to Order” products). This article discusses different approaches to variant management. Starting with the simple Bill of Material (BOM), this article presents three different approaches to variant management, which are provided by Agile PLM. Single level BOM and Variant BOM The single level BOM is the basic form of the BOM. The product structure is defined using assemblies and single parts. A particular product is thus represented by a fixed product structure. As soon as you have to manage product variants, the single level BOM is no longer sufficient. A variant BOM will be needed to manage product variants. The variant BOM is sometimes referred to as 150% BOM, since a variant BOM contains more parts and assemblies than actually needed to assemble the (final) product – just 150% of the parts You can evolve the variant BOM from the single level BOM by replacing single nodes with a placeholder node. The placeholder in this case represents the possible variants of a part or assembly. Product structure nodes, which are part of any product, are so-called “Must-Have” parts. “Optional” parts can be omitted in the final product. Additional attributes allow limiting the quantity of parts/assemblies which can be assigned at a certain position in the Variant BOM. Figure 1 shows the variant BOM of Agile PLM. Figure 1 Variant BOM in Agile PLM During the instantiation of the Variant BOM, the placeholders get replaced by specific variants of the parts and assemblies. The selection of the desired or appropriate variants is either done step by step by the user or by applying pre-defined configuration rules. As a result of the instantiation, an independent BOM will be created (Figure 2). Figure 2 Instantiated BOM in Agile PLM This kind of Variant BOM  can be used for „Assembled –To-Order“ type products as well as for „Engineered-to-Order“-type products. In case of “Assembled –To-Order” type products, typically the instantiation is done automatically with pre-defined configuration rules. For „Engineered- to-Order“-type products at least part of the product is selected manually to make use of customized parts/assemblies, that have been engineered according to the specific custom requirements. Template BOM The Template BOM is used for „Engineered-to-Order“-type products. It is another type of variant BOM. The engineer works in a flexible environment which allows him to build the most creative solutions. At the same time the engineer shall be guided to re-use existing solutions and it shall be assured that product variants of the same product family share the same base structure. The template BOM defines the basic structure of products belonging to the same product family. Let’s take a gearbox as an example. The customer specific configuration of the gearbox is influenced by several parameters (e.g. rpm range, transmitted torque), which are defined in the customer’s requirement document.  Figure 3 shows part of a Template BOM (yellow) and its relation to the product family hierarchy (blue).  Figure 3 Template BOM Every component of the Template BOM has links to the variants that have been engineeried so far for the component (depending on the level in the Template BOM, they are product variants, Assembly Variant or single part variants). This library of solutions, the so-called solution space, can be used by the engineers to build new product variants. In the best case, the engineer selects an existing solution variant, such as the gearbox shown in figure 3. When the existing variants do not fulfill the specific requirements, a new variant will be engineered. This new variant must be compliant with the given Template BOM. If we look at the gearbox in figure 3  it must consist of a transmission housing, a Connecting Plate, a set of Gears and a Planetary transmission – pre-assumed that all components are must have components. The new variant will enhance the solution space and is automatically available for re-use in future variants. The result of the instantiation of the Template BOM is a stand-alone BOM which represents the customer specific product variant. Modular BOM The concept of the modular BOM was invented in the automotive industry. Passenger cars are so-called „Assembled-to-Order“-products. The customer first selects the specific equipment of the car (so-called specifications) – for instance engine, audio equipment, rims, color. Based on this information the required parts will be determined and the customer specific car will be assembled. Certain combinations of specification are not available for the customer, because they are not feasible from technical perspective (e.g. a convertible with sun roof) or because the combination will not be offered for marketing reasons (e.g. steel rims with a sports line car). The modular BOM (yellow structure in figure 4) is defined in the context of a specific product family (in the sample it is product family „Speedstar“). It is the same modular BOM for the different types of cars of the product family (e.g. sedan, station wagon). The assembly or single parts of the car (blue nodes in figure 4) are assigned at the leaf level of the modular BOM. The assignment of assembly and parts to the modular BOM is enriched with a configuration rule (purple elements in figure 4). The configuration rule defines the conditions to use a specific assembly or single part. The configuration rule is valid in the context of a type of car (green elements in figure 4). Color specific parts are assigned to the color independent parts via additional configuration rules (grey elements in figure 4). The configuration rules use Boolean operators to connect the specifications. Additional consistency rules (constraints) may be used to define invalid combinations of specification (so-called exclusions). Furthermore consistency rules may be used to add specifications to the set of specifications. For instance it is important that a car with diesel engine always is build using the high capacity battery.  Figure 4 Modular BOM The calculation of the car configuration consists of several steps. First the consistency rules (constraints) are applied. Resulting from that specification might be added automatically. The second step will determine the assemblies and single parts for the complete structure of the modular BOM, by evaluating the configuration rules in the context of the current type of car. The evaluation of the rules for one component in the modular BOM might result in several rules being fulfilled. In this case the most specific rule (typically the longest rule) will win. Thanks to this approach, it is possible to add a specific variant to the modular BOM without the need to change any other configuration rules.  As a result the whole set of configuration rules is easy to maintain. Finally the color specific assemblies respective parts will be determined and the configuration is completed. Figure 5 Calculated Car Configuration The result of the car configuration is shown in figure 5. It shows the list of assemblies respective single parts (blue components in figure 5), which are required to build the customer specific car. Summary There are different approaches to variant management. Three different approaches have been presented in this article. At the end of the day, it is the type of the product which decides about the best approach.  For „Assembled to Order“-type products it is very likely that you can define the configuration rules and calculate the product variant automatically. Products of type „Engineered-to-Order“ ,however, need to be engineered. Nevertheless in the majority of cases, part of the product structure can be generated automatically in a similar way to „Assembled to Order“-tape products.  That said it is important first to analyze the product portfolio, in order to define the best approach to variant management.

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• Preventing Users From Copying Text From and Pasting It Into TextBoxes

  Many websites that support user accounts require users to enter an email address as part of the registration process. This email address is then used as the primary communication channel with the user. For instance, if the user forgets her password a new one can be generated and emailed to the address on file. But what if, when registering, a user enters an incorrect email address? Perhaps the user meant to enter [email protected], but accidentally transposed the first two letters, entering [email protected]. How can such typos be prevented? The only foolproof way to ensure that the user's entered email address is valid is to send them a validation email upon registering that includes a link that, when visited, activates their account. (This technique is discussed in detail in Examining ASP.NET's Membership, Roles, and Profile - Part 11.) The downside to using a validation email is that it adds one more step to the registration process, which will cause some people to bail out on the registration process. A simpler approach to lessening email entry errors is to have the user enter their email address twice, just like how most registration forms prompt users to enter their password twice. In fact, you may have seen registration pages that do just this. However, when I encounter such a registration page I usually avoid entering the email address twice, but instead enter it once and then copy and paste it from the first textbox into the second. This behavior circumvents the purpose of the two textboxes - any typo entered into the first textbox will be copied into the second. Using a bit of JavaScript it is possible to prevent most users from copying text from one textbox and pasting it into another, thereby requiring the user to type their email address into both textboxes. This article shows how to disable cut and paste between textboxes on a web page using the free jQuery library. Read on to learn more! Read More >

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• switch's mgmt-ip is not remotely reachable.

  - by RainDoctor

  Switch model: Netgear FSM7352PS mgmt-ip: 192.168.1.100/24 Vlan id: 1 (default) There are couple of hosts in this Vlan: 192.168.1.2 (esxi console), for instance. 192.168.1.1 is the firewall/router interface. I can ping 192.168.1.1 and 192.168.1.2 from other vlans, say, 172.31.0.0/24 I can ssh to 192.168.1.2 from 172.31.0.0/24 I can't ping 192.168.1.100 from 172.31.0.0/24 However, I can ping 192.168.1.100 from 192.168.1.2 or from my laptop connected to that vlan (192.168.1.11). I can connect to the web GUI from my laptop when I am in that Vlan. Can anyone shed some light on why I am not able to connect from other vlans?

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• How do I make compiling code not bring my system to its knees?

  - by Jason Baker

  I have a macbook with snow leopard and 2 gigs of RAM. When I compile C or C++ code, my system becomes all but unusable. For instance, when I compile llvm I notice that there are about 10 or 11 processes (cc1plus) getting launched at a time that suck up my CPU time and memory. Is there any way to maybe make it compile less at one time? I'll gladly wait a while longer to have my system usable while I'm compiling. Or is this something that you just have to live with when compiling C or C++?

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• SharePoint Unit Testing and Load Testing Finally?

  - by Kit Ong

  It has always been a real pain to incorporate extensive SharePoint Unit Testing and Load Testing in a project, could Visual Studio 2012 finally make this easier? It certaining looks like it, here's a brief overview on SharePoint support in Visual Studio 2012. Load testing – We now support load testing for SharePoint out of the box. This is more involved than you might imagine due to how dynamic SharePoint is. You can’t just record a script and play it back – it won’t work because SharePoint generates and expects dynamic data (like GUIDs). We’ve built the extensions to our load testing solution to parse the dynamic SharePoint data and include it appropriately in subsequent requests. So now you can record a script and play it back and we will dynamically adjust it to match what SharePoint expects.Unit testing – One of the big problems with unit testing SharePoint is that most code requires SharePoint to be running and trying to run tests against a live SharePoint instance is a pain. So we’ve built a SharePoint “emulator” using our new VS 2012 Fakes & Stubs capability. This will make unit testing of SharePoint components WAY easier.Read more in the link belowhttp://blogs.msdn.com/b/bharry/archive/2012/09/12/visual-studio-update-this-fall.aspx

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• Edit files from Cyberduck in an existing Vim window

  - by Eli Gundry

  I use Cyberduck as my go to FTP client on Windows. I have but one complaint, and that is whenever I click the edit button to edit the remote file with a local version of gVim, it opens in a new window/instance of Vim. This leads to a cluttered desktop as well as not allowing the AutoComplPop to work at it's full potential. What I would like to be able to do is automatically open every file in a new buffer inside of an existing gVim buffer instead of a new window, kind of like the Windows version of gVim and how it has the option to edit a file in a new buffer. Is there anyway to do this in Cyberduck/gVim setting?

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• getaddrinfo: command not found

  - by jebbie

  I've installed a new Ubuntu 12.04 on an AWS EC2 instance and everything worked fine till now. I followed the instructions in this great tutorial: http://www.exratione.com/2012/05/a-mailserver-on-ubuntu-1204-postfix-dovecot-mysql/ Now i'm on the point "installing monit" and when i restart the service i get this error message now: monit: Cannot translate '(none)' to FQDN name -- Name or service not known I started googling and someone is writing there, that monit uses getaddrinfo in his startup-process to determine the hostname. Ok, so i thought i try out on myself what is getaddrinfo delivering, and then i got: getaddrinfo: command not found I guess, something is missing on my system. Can anyone help?

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• Types of semantic bugs, logic errors [closed]

  - by C-Otto

  I am a PhD student and currently focus on automatically finding instances of new types of bugs in (Java) programs that cannot be found by existing tools like FindBugs. The existing tool currently is used to prove/disprove termination of (Java) programs. I have some ideas (see below), but I could need more input from you (experienced programmers, potential users of my tool). What kind of bugs do you wish to find? What types of bugs exist and might be suitable for my analysis? One strength of the approach I use is detailled information about the heap. So in contrast to FindBugs, I can work with knowledge of the form "variable x and variable y are disjoint on the heap" or "variable z is not cyclic". It is also possible to see if a method might have side effects (and if so, which variables may/may not be affected by it). Example 1: Vacuous call: Graph graphOne = createGraph(); Graph graphTwo = createGraph(); Node source = graphTwo.getRootNode(); for (Node n : graphOne.getNodes()) { if (areConnected(source, n)) { graphTwo.addNode(n); } } Imagine createGraph() creates a fresh graph, so that graphOne and graphTwo are disjoint on the heap. Then, because source is taken from graphTwo instead of graphOne, the call to areConnected always returns false. In this situation I could find out that the call areConnected is useless (because it does not have any side effect and the return value always is false) which helps finding the real bug (taking source from the wrong graph). For this the information that x and y are disjoint (because graphOne and graphTwo are disjoint) is crucial. This bug is related to calling x.equals(y) where x and y are objects of different classes. In this scenario, most implementations of equals() always return false, which most likely is not the intended result. FindBugs already finds this bug (hardcoded to equals(), semantics of implementation is not checked). Example 2: Useless code: someCode(); while (something()) { yetMoreSomething(); } moreCode(); In the case that the loop (so the code in something() and yetMoreSomething()) does not modify anything visible outside the loop, it does not make sense to run this code - the program has the same behaviour as someCode(); moreCode() (i.e., without the loop). To find this out, one needs detailled information about the side effects of the (possibly useless) code. If I can prove that the code does not have any side effect that can be observed afterwards (in the example: in moreCode() or later), then the code indeed is useless. Of course, here Input/Output of any form must be seen as a side effect, so that a System.out.println(...) is not considered useless. Example 3: Ignored return value: Instead of x = foo(); and making use of x, the method is called without storing the result: foo();. If the method does not have any side effect, its invocation is useless and can be dropped. Most likely, the bug here is that the returned value should have been used. Here, too, detailled information about side effects are needed. Can you think of similar types of bugs that might be detected (only) with detailled information about the heap, side effects, semantics of called methods, ...? Did you encounter bugs related to the ones shown below in "real life"? By the way, the tool is AProVE and Java related publications can be found on my homepage. Thanks a lot, Carsten

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• Can't star SSH on Ubuntu 12.10 AWS EC2

  - by Conor H

  So i've just started playing around with Ubuntu on Amazon EC2. I've just issued the following command to restart ssh but it has now "killed" ssh. sudo /etc/init.d/ssh restart I can't seem to ssh to this instance anymore. Putty just gives me "connection refused". NOTE: In this case I just restarted SSH to see the result. I didn't change any settings. This was to confirm that it was the restart command was the problem and not any configs I made. What is the correct way to restart SSH? P.S. That usually works on other Ubuntu boxes. Thanks. EDIT: It is also worth noting that when I ran that command I was taken straight back to a prompt. I didn't get any output on the console.

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• Materialized View vs POJO View based on Objects representing Oracle tables

  - by Zack Macomber

  I have about 12 Oracle tables that represent data that's being integrated from an external system into my web application. This data is going to be used in an informational and comparative manner for the clients using my web application. On one particular page of my web application, I need to combine data from 3 - 5 Oracle tables for display as an HTML table on the page. We are NOT currently using a framework (Apache Struts for instance) and we're not in a position to move this Java web application into one at this moment (I'm trying to get us there...). I am certainly not an architect, but I see one of two ways that I can effectively build this page (I know there are other ways, but these seem like they would be good ones...): 1. Create an Oracle Materialized View that represents what the HTML table should look like and then create a POJO based on the View that I can then integrate into my JSP. 2. Create POJOs that represent the Oracle tables themselves and then create another POJO that is the View used for the HTML table and then integrate that POJO into my JSP. To me, it seems the Materialized View would possibly offer quicker results which is always what we strive for in web applications. But, if I just create 12 POJOs that represent the Oracle tables and then build POJO Views off of those, I have the advantage of keeping all the code in one place for this and possibility for creating any number of different views and reusable components in my web application. Any thoughts on which one might be the better route? Or, maybe you know of an even better one?

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• rsync to EC2: Identity file not accessible

  - by Richard

  I'm trying to rsync a file over to my EC2 instance: rsync -Paz --rsh "ssh -i ~/.ssh/myfile.pem" --rsync-path "sudo rsync" file.pdf [email protected]:/home/ubuntu/ This gives the following error message: Warning: Identity file ~/.ssh/myfile.pem not accessible: No such file or directory. [email protected]'s password: The pem file is definitely located at the path ~/.ssh/myfile.pem, though: vi ~/.ssh/myfile.pem shows me the file. If I remove the remote path from the very end of the rsync command: rsync -Paz --rsh "ssh -i ~/.ssh/myfile.pem" --rsync-path "sudo rsync" file.pdf [email protected] Then the command appears to work... building file list ... 1 file to consider file.pdf 41985 100% 8.79MB/s 0:00:00 (xfer#1, to-check=0/1) sent 41795 bytes received 42 bytes 83674.00 bytes/sec total size is 41985 speedup is 1.00 ...but when I go to the remote server, nothing has actually been transferred. What am I doing wrong?

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• Teredo - how to connect to host behind NAT?

  - by Signum

  All I want to achieve is to establish connection to my simple server (written in C# using TcpListener class, if it makes any difference), on my computer which is behind NAT. It has some IPv6 address (it's public IP, starting with 2001:0) on Teredo interface. However, I cannot even ping it from outside my network, for instance I'm trying to ping this address from this website http://mebsd.com/ipv6-ping-and-traceroute, result - 100% packet loss. As I understood from reading about Teredo, there is no need for some port forwarding? So where could be the problem?

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• PostgreSQL 9: Does Vacuuming a table on the primary replicate on the mirror?

  - by Scott Herbert

  Running PostgreSQL 9.0.1, with streaming replication keeping one read-only mirror instance up to date. Auto-vaccuum is on on the primary, except for a few tables which are not vacuumed by the auto-vacuum daemon, in an effort to reduce business-hour IO. These tables are "materialised views". Each night at midnight, we run a vacuum across the database in order to clean up those tables that are excluded from the auto-vacuum. I'm wondering if that process replicates across to the mirror, or if I need to set up vacuum on the mirror as well?

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• MySQL Database synchronizing with local and remote with c#

  - by Neo

  I've posted this here as its more of a mysql questions than c#, I have written some software that runs a local instance of mysql when it first starts, now once mysql is up I would like to synchronize the data between the remote database table and the local database table that the software runs (it shouldn't sync any other databases / tables as there are a lot). I have replication setup to synchronize the entire database to another server which works unless the server goes down then it never comes back up, so based on that I don't think replication will work as when the software is closed it also closes MySQL. So what would be the best method of synchronizing the remote and local databases?

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• SQL Server Express Uninstall / Enterprise Install Issue

  - by user19049

  I need help installing SQL Server 2005 Enterprise edition.I really need to remove the current SQL Server 2005.installation that is no longer on my Add/Remove software list but yet still installed on the machine. I tried to uninstall SQL Server Express / Developer Edition but it only removed it from my Add/Remove software list. It returned immediately but did NOT actually remove the product. (I'm now in a bad state.) i tried to install SQL Server 2005 Enterprise and its says I'm blocked as all components are already installed - but they are not. How can I remove all instance of previous one and install clean Enterprise edition on my server Thanks

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• debian - running unattended-upgrades on a particular day of the week

  - by dastra

  We're running unattended-upgrades on debian squeeze, and would like it to run once a week, only on a Wednesday morning. To attempt this, we have set: APT::Periodic::Unattended-Upgrade "7" in /etc/apt/apt.conf.d/50unattended-upgrades And then touched the /var/lib/apt/periodic/update-stamp to set the timestamp to a Wednesday, for instance: touch -t 201211280000 /var/lib/apt/periodic/update-stamp Running: stamp=$(date --date=$(date -r /var/lib/apt/periodic/update-stamp --iso-8601) +%s 2/dev/null) date -u --date="1970-01-01 $stamp sec GMT" Gives the correct timestamp: Wed Nov 28 00:00:00 UTC 2012 However, unattended-upgrades then seems to ignore this, and run the updates on a Saturday morning. Could anyone enlighten me as to how this parameter works, and how to set up upgrades to run on a Wednesday?

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• Switches with 802.1x "supplicant timeout" feature?

  - by chris

  I'm looking for a complete list of switches which will allow 802.1x and normal (non-supplicant) enabled hosts to connect to the same ports on a switch. This is useful for areas where there are semi-open ports such as a lobby area or a library where corporate and guest users may use the same ports but you want them to have different access profiles and where it isn't expected that guests would have 802.1x configured on their system. For instance, Enterasys and Extreme Networks both have a feature where if the switch doesn't see an EAPOL packet from the client in a certain amount of time, it puts the port into a "guest" VLAN; if it sees an 802.1x supplicant, it tries to authenticate the user via 802.1x and if they succeed, it does what the radius server tells it to do with that port (IE put the port into a certain VLAN, apply certain ACLs, etc) Do other vendors have this sort of feature, or is it expected that a switch will do both 802.1x and MAC authentication, and the "supplicant timeout" feature is implemented with a blanket allow on the MAC authentication?

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• Python or Ruby in 2011.

  - by Sleeper Smith

  What I'm really asking is, in the current services and technologies provided, which is a more "useful" language? Which one has more opportunity? Some background info first. I'm a .net C# dev for 5 years. Having done a few projects on Amazon AWS, I'm looking to start a few projects of my own. But Azure's too expensive, and AWS has too much management overhead. My current choice is Google App Engine and Python. Logical enough. But what I want to ask here is this: In Linux world, which is more useful? Recently heard about Heroku for Ruby. How viable is this? Looking at the pricing model indicates that it's more expensive. Which one has more up-to-date and exciting open source projects? For instance Trac is just plain out dated compared to Redmine. One of the big reason pulling me for Ruby is Redmine. Implementations? IronPython/IronRuby/JRuby etc etc. Which one is more standardised and more implementation agnostic? Which one is easier to port between Windows/Linux? Anyway, your input and thoughts are greatly appreciated. thanks.

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• Code Behaviour via Unit Tests

  - by Dewald Galjaard

  Normal 0 false false false EN-ZA X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Some four months ago my car started acting up. Symptoms included a sputtering as my car’s computer switched between gears intermittently. Imagine building up speed, then when you reach 80km/h the car magically and mysteriously decide to switch back to third or even second gear. Clearly it was confused! I managed to track down a technician, an expert in his field to help me out. As he fitted his handheld computer to some hidden port under the dash, he started to explain “These cars are quite intelligent, you know. When they sense something is wrong they run in a restrictive program which probably account for how you managed to drive here in the first place...”  I was surprised and thought this was certainly going to be an interesting test drive. The car ran smoothly down the first couple of stretches as the technician ran through routine checks. Then he said “Ok, all looking good. We need to start testing aspects of the gearbox. Inside the gearbox there are a couple of sensors. One of them is a speed sensor which talks to the computer, which in turn will decide which gear to switch to. The restrictive program avoid these sensors altogether and allow the computer to obtain its input from other [non-affected] sources”. Then, as soon as he forced the speed sensor to come back online the symptoms and ill behaviour re-emerged... What an incredible analogy for getting into a discussion on unit testing software? Besides I should probably put my ill fortune to some good use, right? This example provide a lot of insight into how and why we should conduct unit tests when writing code. More importantly, it captures what is easily and unfortunately often the most overlooked goal of writing unit tests by those new to the art and those who oppose it alike - The goal of writing unit tests is to test the behaviour of our code under predefined conditions. Although it is very possible to test the intrinsic workings of each and every component in your code, writing several tests for each method in practise will soon prove to be an exhausting and ultimately fruitless exercise given the certain and ever changing nature of business requirements. Consequently it is true and quite possible whilst conducting proper unit tests, to call any single method several times as you examine and contemplate different scenarios. Let’s write some code to demonstrate what I mean. In my example I make use of the Moq framework and NUnit to create my tests. Truly you can use whatever you’re comfortable with. First we’ll create an ISpeedSensor interface. This is to represent the speed sensor located in the gearbox.  Then we’ll create a Gearbox class which we’ll pass to a constructor when we instantiate an object of type Computer. All three are described below.   ISpeedSensor.cs namespace AutomaticVehicle {     public interface ISpeedSensor     {         int ReportCurrentSpeed();     } }   Gearbox.cs namespace AutomaticVehicle {      public class Gearbox     {         private ISpeedSensor _speedSensor;           public Gearbox( ISpeedSensor gearboxSpeedSensor )         {             _speedSensor = gearboxSpeedSensor;         }         /// <summary>         /// This method obtain it's reading from the speed sensor.         /// </summary>         /// <returns></returns>         public int ReportCurrentSpeed()         {             return _speedSensor.ReportCurrentSpeed();         }     } } Computer.cs namespace AutomaticVehicle {     public class Computer     {         private Gearbox _gearbox;         public Computer( Gearbox gearbox )         {                     }          public int GetCurrentSpeed()         {             return _gearbox.ReportCurrentSpeed( );         }     } } Since this post is about Unit testing, that is exactly what we’ll create next. Create a second project in your solution. I called mine AutomaticVehicleTests and I immediately referenced the respective nunit, moq and AutomaticVehicle dll’s. We’re going to write a test to examine what happens inside the Computer class. ComputerTests.cs namespace AutomaticVehicleTests {     [TestFixture]     public class ComputerTests     {         [Test]         public void Computer_Gearbox_SpeedSensor_DoesThrow()         {             // Mock ISpeedSensor in gearbox             Mock< ISpeedSensor > speedSensor = new Mock< ISpeedSensor >( );             speedSensor.Setup( n => n.ReportCurrentSpeed() ).Throws<Exception>();             Gearbox gearbox = new Gearbox( speedSensor.Object );               // Create Computer instance to test it's behaviour  towards an exception in gearbox             Computer carComputer = new Computer( gearbox );             // For simplicity let’s assume for now the car only travels at 60 km/h.             Assert.AreEqual( 60, carComputer.GetCurrentSpeed( ) );          }     } }   What is happening in this test? We have created a mocked object using the ISpeedsensor interface which we've passed to our Gearbox object. Notice that I created the mocked object using an interface, not the implementation. I’ll talk more about this in future posts but in short I do this to accentuate the fact that I'm not not really concerned with how SpeedSensor work internally at this particular point in time. Next I’ve gone ahead and created a scenario where I’ve declared the speed sensor in Gearbox to be faulty by forcing it to throw an exception should we ask Gearbox to report on its current speed. Sneaky, sneaky. This test is a simulation of how things may behave in the real world. Inevitability things break, whether it’s caused by mechanical failure, some logical error on your part or a fellow developer which didn’t consult the documentation (or the lack thereof ) - whether you’re calling a speed sensor, making a call to a database, calling a web service or just trying to write a file to disk. It’s a scenario I’ve created and this test is about how the code within the Computer instance will behave towards any such error as I’ve depicted. Now, if you’ve followed closely in my final assert method you would have noticed I did something quite unexpected. I might be getting ahead of myself now but I’m testing to see if the value returned is equal to what I expect it to be under perfect conditions – I’m not testing to see if an error has been thrown! Why is that? Well, in short this is TDD. Test Driven Development is about first writing your test to define the result we want, then to go back and change the implementation within your class to obtain the desired output (I need to make sure I can drive back to the repair shop. Remember? ) So let’s go ahead and run our test as is. It’s fails miserably... Good! Let’s go back to our Computer class and make a small change to the GetCurrentSpeed method.   Computer.cs public int GetCurrentSpeed() {   try   {     return _gearbox.ReportCurrentSpeed( );   }   catch   {     RunRestrictiveProgram( );   } }     This is a simple solution, I know, but it does provide a way to allow for different behaviour. You’re more than welcome to provide an implementation for RunRestrictiveProgram should you feel the need to. It's not within the scope of this post or related to the point I'm trying to make. What is important is to notice how the focus has shifted in our approach from how things can break - to how things behave when broken.   Happy coding!

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• Browser with its own hosts file?

  - by Mystere Man

  I have a number of staging and test servers that I need to constantly modify my hosts file to access (they depend on the domain name, so i have to change the hosts file to get them to work). I find this annoying. I'd like to setup a portable browser of some kind for each kind of site i want to work with. Is there any version of any graphical web browser (including browsers based on the rendering engines of other browsers) that will do this? This way i can simply launch the instance that's already configured to work with staging if i want to test staging. Any ideas?

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• Computer Randomly Restarts (no crash dump)

  - by Bruno Charters

  Hey everyone this is my first time here, so, my computer got pulled out of his place the other day by accident and it never got back to working decently ever again. I just stopped using it because everytime i power it on, it restarts. Some times it doesn't even reach the desktop, others it even allows me to run a game or something. It gets really random. Today i was trying my last attempt before sending it to fix and it ran fine for 40 minutes but as i tried to run a game the screen got really messeud up full of colorful lines and stuff and i'm assuming it had to do with the graphics card. Altho, my question is, what can be causing all this restart thingie? Can it be just the Power Supply failing me and hence, not giving enough power to make the graphic card go for instance? My computer specs are: Motherboard: Asus P5KPL - AM CPU: Intel QuadCore 2.33 ghz Graphic Card: Nvidia GeForce GTS260 Ram: 2x2gb ddr2 Power Supply: Nox Urano 500W Thanks in advance, Bruno Charters

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• JMX Monitoring of GlassFish Servers

  - by tjquinn

  Did you ever wonder what this message in your GlassFish server.log file means? JMXStartupService has started JMXConnector on JMXService URL service:jmx:rmi://192.168.2.102:8686/jndi/rmi://192.168.2.102:8686/jmxrmi It means you can monitor any GlassFish server process, remotely or locally, using any standard Java Management Extensions (JMX) client.  Examples: jconsole or jvisualvm.   Copy the part of the log message that starts with "service:" into the Add JMX Connection dialog of jvisualvm:  or into the New Connection dialog of jconsole: (The full string is truncated in the on-screen display, but if you copied from the server.log and pasted into the form it should all be there.) The examples above are for a DAS, and your host will probably be different.   The server.log files for other GlassFish servers (instances) will have similar log entries giving the JMX connection string to use for those processes.  Look for the host and/or port to be different. Note a few things about security: Here we've assumed you are using the default admin username and password.  If you are not, just enter a valid admin username and password for your installation.  Once connected, you have normal access to all the JVM statistics and controls. You can use JMX clients that support MBeans to view the GlassFish configuration.  When you connect to the DAS, you can also change that configuration, but you can only view configuration when you connect to an instance. To use a JMX client on one system to connect to a GlassFish server running on another system, you need to enable secure admin if you have not already done so: asadmin change-admin-password (respond to the prompts) asadmin enable-secure-admin asadmin restart-domain (as prompted in the output from enable-secure-admin)

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• HD latency measurement using bonnie++ on different machines with different RAM size

  - by j0nes

  Hello, I have run bonnie++ v1.96 on two different servers without any additional load. One server is a "physical" Dell server with 32GB RAM, the other one is a virtual instance with 14GB RAM. I have read in the bonnie manuals that I should use two times the size of RAM in my bonnie runs, so I used 64GB on the physical machine and 28GB on the virtual machine. Now I want to compare the results, and I am wondering whether the results are comparable at all. The most interesting part is the latency part - on the physical machine, the values are about 10 times higher than on the virtual machine! Can I take these results seriously (e.g. the virtual machine HD is much much faster) or does the different RAM size tamper the results? Thanks! Jonas

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