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  • Problem -- My Android "Hello World" App Won't Say 'Hello"

    - by keith
    Hello, I hope that I have come to the right post for a beginner’s question abut Android programming. If not, please feel free to direct me to a better forum. I created a hello world application, and the system generated most of the Android language below. When running the app without the system.out statement, there is no “hello” in the emulator. Then, using the Eclipse tutorial, I read that I can add the system.out.println statement to main. Again the app runs, but there is no output. What am I not understanding here? android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello" System.out.println =" Hello world!" / Thank you, Keith

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  • Developing Installer Packages, are Visual Studio Setup Projects suitable for complex setups

    - by Robert
    Are "Visual Studio Setup" Projects suitable for complex setups in different versions? The application is rather large ( 500.000 lines of code) and is under continuous development. Every 6 to 10 month a new version gets released. We have multiple configuration files (INI and XML), registry keys, database migration scripts, etc. The application is in the progress of being migrated from VB6 to .NET . The old installer was build with Installshield. The feedback to Installshield is: Bad adaptability, bad reuse - thats way we are evaluating "Visual Studio Setup" as an alternative. Other products we consider: Free Solutions WiX NSIS Commercial Solutions Installshield (again..) Wise Advanced Installer sth. missing? Solutions we don't like to consider: Inno Setup (It just doesn't feel right)

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  • An MCM exam, Rob? Really?

    - by Rob Farley
    I took the SQL 2008 MCM Knowledge exam while in Seattle for the PASS Summit ten days ago. I wasn’t planning to do it, but I got persuaded to try. I was meaning to write this post to explain myself before the result came out, but it seems I didn’t get typing quickly enough. Those of you who know me will know I’m a big fan of certification, to a point. I’ve been involved with Microsoft Learning to help create exams. I’ve kept my certifications current since I first took an exam back in 1998, sitting many in beta, across quite a variety of topics. I’ve probably become quite good at them – I know I’ve definitely passed some that I really should’ve failed. I’ve also written that I don’t think exams are worth studying for. (That’s probably not entirely true, but it depends on your motivation. If you’re doing learning, I would encourage you to focus on what you need to know to do your job better. That will help you pass an exam – but the two skills are very different. I can coach someone on how to pass an exam, but that’s a different kind of teaching when compared to coaching someone about how to do a job. For example, the real world includes a lot of “it depends”, where you develop a feel for what the influencing factors might be. In an exam, its better to be able to know some of the “Don’t use this technology if XYZ is true” concepts better.) As for the Microsoft Certified Master certification… I’m not opposed to the idea of having the MCM (or in the future, MCSM) cert. But the barrier to entry feels quite high for me. When it was first introduced, the nearest testing centres to me were in Kuala Lumpur and Manila. Now there’s one in Perth, but that’s still a big effort. I know there are options in the US – such as one about an hour’s drive away from downtown Seattle, but it all just seems too hard. Plus, these exams are more expensive, and all up – I wasn’t sure I wanted to try them, particularly with the fact that I don’t like to study. I used to study for exams. It would drive my wife crazy. I’d have some exam scheduled for some time in the future (like the time I had two booked for two consecutive days at TechEd Australia 2005), and I’d make sure I was ready. Every waking moment would be spent pouring over exam material, and it wasn’t healthy. I got shaken out of that, though, when I ended up taking four exams in those two days in 2005 and passed them all. I also worked out that if I had a Second Shot available, then failing wasn’t a bad thing at all. Even without Second Shot, I’m much more okay about failing. But even just trying an MCM exam is a big effort. I wouldn’t want to fail one of them. Plus there’s the illusion to maintain. People have told me for a long time that I should just take the MCM exams – that I’d pass no problem. I’ve never been so sure. It was almost becoming a pride-point. Perhaps I should fail just to demonstrate that I can fail these things. Anyway – boB Taylor (@sqlboBT) persuaded me to try the SQL 2008 MCM Knowledge exam at the PASS Summit. They set up a testing centre in one of the room there, so it wasn’t out of my way at all. I had to squeeze it in between other commitments, and I certainly didn’t have time to even see what was on the syllabus, let alone study. In fact, I was so exhausted from the week that I fell asleep at least once (just for a moment though) during the actual exam. Perhaps the questions need more jokes, I’m not sure. I knew if I failed, then I might disappoint some people, but that I wouldn’t’ve spent a great deal of effort in trying to pass. On the other hand, if I did pass I’d then be under pressure to investigate the MCM Lab exam, which can be taken remotely (therefore, a much smaller amount of effort to make happen). In some ways, passing could end up just putting a bunch more pressure on me. Oh, and I did.

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  • Reverse geocode without using MKReverseGeocoder

    - by SpH1nX
    Hi guys, I'm trying to detect current user address using MKReverseGeocoder passing coordinates obtained via CLLocation class. Reading MKReverseGeocoder Class Reference I noticed that The Google terms of service require that the reverse geocoding service be used in conjunction with a Google map; take this into account when designing your application's user interface. so I'm wondering if (and eventually how) can I reverse geocode user current location on iPhone OS SDK 3.1.3. I thought using Google Maps API but the EULA has the same obligation. Yahoo Maps API is even worse and Microsoft one aren't free.

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  • Looking For a .NET Task Scheduling library

    - by Hounshell
    I'm looking for the following features: Scheduler uses SQL Server as the backing store Tasks can be scheduled by one application and executed by another I can have multiple applications, each of which handles a specific subset of tasks Tasks can be triggered at specific times, now, or based on the success or failure of other tasks Data can be attached to tasks There are a number of nice-to-have's, like a web management console, clustering/failover support, customizable logging, but they're not requirements. On the surface Quartz.NET has a nice interface and seems to fit the bill as it satisfies (1), (4 with some custom work) and (5), but I've been beating my head against (2) and (3) seems like I'd have to invest more effort than it's worth, especially given how convoluted the innards of it are. Any other libraries out there? Open source is preferred, with free as a close runner up. It's really hard to get management to pay for things like this when it's not their idea.

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  • LINQPad - Dump extension method - I want one!

    - by gav
    Hi, LINQPad is amazing, particularly useful is the Dump() extension methods which renders objects and structs of almost any type, anonymous or not, to the console. Initially, when I moved to Visual Studio 2010, I tried to make my own Dump method using a delegate to get the values to render for anonymous types etc. It's getting pretty complicated though and whilst it was fun and educational at first what I need is a solid implementation. Having checked out the LinqPad code in reflector I am even more assured that I'm not going to get the implementation right. Is there a free library I can include to provide the Dump functionality? Thanks, Gavin

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  • Perforce command line only showing local users/changelists/workspaces, but P4V shows all

    - by M Katz
    We are using P4 for free with two users. In the P4V admin gui I can see both myself and my partner as users, and in the P4V gui I can see all workspaces (clients) and all changelists (both mine and my partner's). From the command line, 'p4 users' only shows me, 'p4 clients' only shows my local workspace, etc. Is there some mode, environment setting, or special directory from which I have to use the p4 command line to see those global objects? I believe I am a p4 superuser (since I read this is the default on installation and we didn't change anything). I'm obviously missing something very basic about the relationship between p4 command line and P4V. The reason I need to use the command line is to delete an old client workspace (used on a different machine) that has an empty changelist associated with it. I therefore need to use 'p4 client -d -f old-workspace-name' from the command line. But when I do it tells me client 'old-workspace-name' doesn't exist.

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  • Photoshop JSX script- CLOSE PHOTOSHOP!

    - by Geekay2
    How do I close photoshop using its javascript scripting language. (I am automaticly scripting a great deal of things, and I notice that for one reason or another, some of the ram is not releasing with each new task. My hopes are that after X ammount of operations, I will fully close photoshop, to free up the ram.. which it is eating up all of my 8 gigs, and after which then opens photoshop help and causes a huge failure (actually, to be honest it fills up my hard drive with junk till I get a "hard drive is full" message... (I think it is dumping the ram into virtual ram on my hard drive?)... what a mess)THANKS!!

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  • Recommended resources for learning MS Expression Blend

    - by fastmonkeywheels
    I've been designing applications using C# for some time now but I have the need to create a more custom application and Expression Blend was recommended to me. I've downloaded the free trial but it's a little fancier than I expected. I'm not a graphic designer and can't use photoshop to save my life, however I do have images provided by a graphic designer to use for this application. I'm looking for some good resources for learning Blend and using it as a front end to a C# application, much like I would a regular C# forum.

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  • Is there a website to lookup common, already written functions?

    - by pinnacler
    I'm sitting here writing a function that I'm positive has been written before, somewhere on earth. It's just too common to have not been attempted, and I'm wondering why I can't just go to a website and search for a function that I can then copy and paste into my project in 2 seconds, instead of wasting my day reinventing the wheel. Sure there are certain libraries you can use, but where do you find these libraries and when they are absent, is there a site like I'm describing? Possibly a wiki of some type that contains free code that anybody can edit and improve?

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  • Messaging Systems – Handshaking, Reconciliation and Tracking for Data Transparency

    - by Ahsan Alam
    As many corporations build business partnerships with other organizations, the need to share information becomes necessary. Large amount of data sharing using snail mail, email and/or fax are quickly becoming a thing of the past. More and more organizations are relying heavily on Ftp and/or Web Service to exchange data. Corporations apply wide range of technologies and techniques based on available resources and data transfer needs. Sometimes, it involves simple home-grown applications. Other times, large investments are made on products like BizTalk, TIBCO etc. Complexity of information management also varies significantly from one organizations to another. Some may deal with handful of simple steps to process and manage shared data; whereas others may rely on fairly complex processes with heavy interaction with internal and external systems in order to serve the business needs. It is not surprising that many of these systems end up becoming black boxes over a period of time. Consequently, people and business start to rely more and more on developers and support personnel just to extract simple information adding to the loss of productivity. One of the most important factor in any business is transparency to data irrespective of technology preferences and the complexity of business processes. Not knowing the state of data could become very costly to the business. Being involved in messaging systems for some time now, I have heard the same type of questions over and over again. Did we transmit messages successfully? Did we get responses back? What is the expected turn-around-time? Did the system experience any errors? When one company transmits data to one or more company, it may invoke a set of processes that could complete in matter of seconds, or it could days. As data travels from one organizations to another, the uncertainty grows, and the longer it takes to track uncertain state of the data the costlier it gets for the business, So, in every business scenario, it's extremely important to be aware of the state of the data.   Architects of messaging systems can take several steps to aid with data transparency. Some forms of data handshaking and reconciliation mechanism as well as extensive data tracking can be incorporated into the system to provide clear visibility to the data. What do I mean by handshaking and reconciliation? Some might consider these to be a single concept; however, I like to consider them in two unique categories. Handshaking serves as message receipts or acknowledgment. When one transmits messages to another, the receiver must acknowledge each message by sending immediate responses for each transaction. Whenever we use Web Services, handshaking is often achieved utilizing request/reply pattern. Similarly, if Ftp is used, a receiver can acknowledge by dropping messages for the sender as soon as the files are picked up. These forms of handshaking or acknowledgment informs the message sender and receiver that a successful transaction has occurred. I have mentioned earlier that it could take anywhere from a few seconds to a number of days before shared data is completely processed. In addition, whenever a batched transaction is used, processing time for each data element inside the batch could also vary significantly. So, in order to successfully manage data processing, reconciliation becomes extremely important; otherwise it may result into data loss or in some cases hefty penalty. Reconciliation can be done in many ways. Partner organizations can share and compare ad hoc reports to achieve reconciliation. On the other hand, partners can agree on some type of systematic reconciliation messages. Systems within responsible parties can trigger messages to partners as soon as the data process completes.   Next step in the data transparency is extensive data tracking. Some products such as BizTalk and TIBCO provide built-in functionality for data tracking; however, built-in functionality may not always be adequate. Sometimes additional tracking system (or databases) needs to be built in order monitor all types of data flow including, message transactions, handshaking, reconciliation, system errors and many more. If these types of data are captured, then these can be presented to business users in any forms or fashion. When business users are empowered with such information, then the reliance on developers and support teams decreases dramatically.   In today's collaborative world of information sharing, data transparency is key to the success of every business. The state of business data will constantly change. However, when people have easier access to various states of data, it allows them to make better and quicker decisions. Therefore, I feel that data handshaking, reconciliation and tracking is very important aspect of messaging systems.

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  • PrestaShop vs. Shopify

    - by Zach L.
    I have seen several Questions comparing different ECommerce CMS's: Prestashop compared to Zen-Cart and osCommerce Magento or Prestashop, which is better? Best php/ruby/python e-commerce solution I was hoping to get some people to weigh in with which they prefer for a relatively small E-shop. I am now primarily looking at PrestaShop and Shopify. I really like that Shopify does the hosting, has quality service, and is simple to understand and theme. However PrestaShop is free and seems to be able to do just as much if not more than Shopify. I have decided that Magento is too clunky for the project, and have read that many other solutions (osCommerce, ZenCart, OpenCart) are outdated, buggy, or just inferior. Thank you!

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  • Hide header and footer when printing from Internet Explorer using Javascript or CSS

    - by molasses
    When I print a webpage from Internet Explorer it will automatically add a header and footer including the website title, URL, date, and page number. Is it possible to hide the header and footer programatically using Javascript or CSS? Requirements: works in IE 6 (no other browser support necessary as its for an Intranet) may use ActiveX, Java Applet, Javascript, CSS preferably not something that the user needs to install (eg. http://www.meadroid.com/scriptx). feel free to list other third party available plug-ins though as I think this may be the only option don't require the user to manually update their browser settings don't render the pages as PDF or Word document or any other format don't write to the registry (security prevents this) Thanks

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  • From Bluehost to WP Engine, My WordPress Story

    - by thatjeffsmith
    This is probably the longest blog post I’ve written in a LONG time. And if you’re used to coming here for the Oracle stuff, this post is not about that. It’s about my blog, and the stuff under the hood that makes it run, AKA WordPress. If you want to skip to the juicy stuff, then use these shortcuts: My Site Slowed Down How I Moved to WP Engine How WP Engine ‘Hooked’ Me Why WP Engine? I started thatJeffSmith.com on May 28th, 2010. I had been already been blogging for several years, but a couple of really smart people I respected (Andy, Brent – thanks again!) suggested that I take ownership of my content and begin building my personal brand. I thought that was a good idea, and so I signed up for service with bluehost. Bluehost makes setting up a WordPress site very, very easy. And, they continued to be easy to work with for the past 2 years. I would even recommend them to anyone looking to host their own WordPress install/site. For $83.40, I purchased a year’s worth of service and my domain name registration – a very good value. And then last year I paid $107.40 for another year’s services. And when that year expired I paid another $190.80 for an additional two year’s service in advance. I had been up to that point, getting my money’s worth. And then, just a few weeks ago… My Site Slowed to a Crawl That spike was from an April Fool's Day Post, I think Why? Well, when I first started blogging, I had the same problem that most beginner bloggers have – not many readers. In my first year of blogging, I think the highest number of readers on a single day was about 125. I remember that day as I was very excited to break 100! Bluehost was very reliable, serving up my content with maybe a total of 3-4 outages in the past 2 years. Support was usually very prompt with answers and solutions, and I love their ‘Chat now’ technology – much nicer than message boards only or pay-to-talk phone support. In the past 6 months however, I noticed a couple of things: daily traffic was increasing – woohoo! my service was experiencing severe CPU throttling – doh! To be honest, I wasn’t aware the throttling was occuring, but I did know that the response time of my blog was starting to lag. Average load times were approaching 20-30 seconds. Not good when good sites are loading in 5 seconds or less. And just this past week, in getting ready to launch a new website for work that sucked in an RSS feed from my blog, the new page was left waiting for more than a minute. Not good! In fact my boss asked, why aren’t you blogging on Blogger? Ugh. I tried a few things to fix the problem: I paid for a premium WordPress theme – Themify’s Grido (thanks to @SQLRockstar for the heads-up) I installed a couple of WP caching plugins I read every WP optimization blog post I could get my greedy little eyes on However, at the same time I was also getting addicted to WordPress bloggers talking about all the cool things you could do with your blog. As a result I had at one point about 30 different plugins installed. WordPress runs on MySQL, and certain queries running via these plugins were starving for CPU. Plugins that would be called every page load meant that as more people clicked on my site, the more CPU I needed. I’m not stupid, so I eventually figured out that maybe less plugins was better, and was able to go down to just 20. But still, the site was running like a dog. CPU Throttling, makes MySQL wait to run a query Bluehost runs shared servers. Your site runs on the same box that several hundred (or thousand?) other services are running on. If you take more CPU than they think you should have, they will limit your service by making you stand in line for CPU, AKA ‘throttling.’ This is not bad. This business model allows them to serve many, many users for a very fair price. It works great until, well, until it doesn’t. I noticed in the last week that for every minute of service, I was being throttled between 60 and 300 seconds. If there were 5 MySQL processes running, then every single one of them were being held in check. The blog visitor notice this as their page requests would take a minute or more to be answered. Bluehost unfortunately doesn’t offer dedicated server hosting, so there was no real upgrade path for me follow and remain one of their customers. So what was I to do? Uninstall every plugin and hope the site sped up? Ask for people to take turns on my blog? I decided to spend my way out of the problem. I signed up for service with WP Engine and moved ThatJeffSmith.com The first 2 months are free, and after that it’s about $29/month to run my site on their system. My math tells me that’s a good bit more expensive than what Bluehost was charging me – to the tune of about 300% more a month. Oh, and I should just say that my blog is a personal blog even though I talk about work stuff here. I don’t get paid for blogging, I don’t sell ads, and I don’t expense the service fees – this is my personal passion. So is it worth it? In the first 4 days, it seems to be totally worth it. Load times have gone from 20-30 seconds to less than 5 seconds. A few folks have told me via Twitter that they notice faster page loads. I anticipate this will indirectly lead to more traffic as Google penalizes you in search results if your site is too slow, and of course some folks won’t even bother waiting more than 5-10 seconds. I noticed right away that writing posts, uploading pictures, and just using the WordPress dashboard in general was much more responsive. So writing is less of a chore now, which means I won’t have a good reason not to write How I Moved to WP Engine I signed up for the service and registered my domain. I then took a full export of my ‘old’ site by doing a FTP GET of all my files, then did a MySQL database backup, exported my WordPress Theme settings to a .zip file, and then finally used the WordPress ‘Export’ feature. I then used the WordPress ‘Import’ on the new site to load up my posts. Then I uploaded the theme .zip package from Themify. Then I FTP’d the ‘wp-content’ directory up to my new server using SFTP (WP Engine only supports secure FTP – good on them!) Using a temporary URL to see my new site, I was able to confirm that everything looked mostly OK – I’ll detail the challenges and issues of fixing the content next – but then it was time to ‘flip the switch.’ I updated the IP address that the DNS lookup tables use to route traffic to my new server. In a matter of minutes the DNS servers around the world were updated and it was time to see the new site! But It Was ‘Broken’ I had never moved a website before, and in my rush to update the DNS, I had changed the records without really finding out what I was supposed to do first. After re-reading the directions provided by WP Engine and following the guidance of their support engineer, I realized I had needed to set the CNAME (Alias) ‘www’ record to point to a different URL than the ‘www.thatjeffsmith.com’ entry I had set. Once corrected the site was up and running in less than a minute. Then It Was Only Mostly Broken Many of my plugins weren’t working. Apparently just ftp’ing the wp-content directory up wasn’t the proper way to re-install the plugin. I suspect file permissions or file ownership wasn’t proper. Some plug-ins were working, many had their settings wiped to the defaults, and a few just didn’t work again. I had to delete the directory of the plug-in manually via SFTP, and then use the WP Dashboard to install it from scratch. And here was my first ‘lesson’ – don’t switch the DNS records until you’ve completely tested your new site. I wasn’t able to navigate the old WP console to review my plug-in settings. Thankfully I was able to use the Wayback Machine to reverse engineer some things, and of course most plug-ins aren’t that complicated to setup to begin with. An example of one that I had to redo from scratch is the ‘Twitter @Anywhere Plus’ plugin that I use to create the form that allows folks to tweet a post they enjoyed at the end of each story. How WP Engine ‘Hooked’ Me I actually signed up with another provider first. They ranked highly in Google searches and a few Tweeps recommended them to me. But hours after signing up and I still didn’t have sever reyady, I was ready to give up on them. They offered no chat or phone support – only mail and message boards. And the message boards were rife with posts about how the service had gone downhill in the past 6 months. To their credit, they did make it easy to cancel, although I did have to do so via email as their website ‘cancel’ button was non-existent. Within minutes of activating my WP Engine account I had received my welcome message and directions on how to get started. I was able to see my staged website right away. They also did something very cool before I even got started – they looked at my existing site and told me by how much they could improve its performance. The proof is in the web pudding. I like this for a few reasons, but primarily I liked their business model. It told me they knew what they were doing, and that they were willing to put their money where their mouth was. This was further evident by their 60-day money back guarantee. And if I understand it correctly, they don’t even take your money until after that 60 day period is over. After a day, I was welcomed by the WP Engine social media team, and was given the opportunity to subscribe to their newsletter and follow their account on Twitter. I noticed their Twitter team is sure to post regular WordPress tips several times a day. It’s not just an account that’s setup for the sake of having a Twitter presence. These little things add up and give me confidence in my decision to choose them as my hosting partner. ‘Partner’ – that’s a lot nicer word than just ‘service provider,’ isn’t it? Oh, and they offered me a t-shirt. Don’t ever doubt the power of a ‘free’ t-shirt! How awesome is this e-mail, from a customer perspective? I wasn’t really expecting any of this. Exceeding expectations before I have even handed over a single dollar seems like a pretty good business plan. This is how you treat customers. Love them to death, and they reward you with loyalty. But Jeff, You Skipped a Piece Here, Why WP Engine? I found them on one of those ‘Top 10′ list posts, and pulled up their webpage. I noticed they offered a specialized service – they host WordPress installs, and that’s it. Their servers are tuned specifically for running WordPress. They had in bolded text, things like ‘INSANELY FAST. INFINITELY SCALABLE.’ and ‘LIGHTNING SPEED.’ And then they offered insurance against hackers and they took care of automatic backups and restores. The only drawbacks I have noticed so far relate to plugins I used that have been ‘blacklisted.’ In order to guarantee that ‘lightning’ speed, they have banned the use of the CPU-suckiest plugins. One of those is the ‘Related Posts’ plugin. So if you are a subscriber and are reading this in your email, you’ll notice there’s no links back to my blog to continue reading other related stories. Since that referral traffic is very small single-digit for my site, I decided that I’m OK with that. I’d rather have the warp-speed page loads. Again, I think that will lead to higher traffic down the road. In 50+ days I will need to decide if WP Engine is a permanent solution. I’ll be sure to update this post when that time comes and let y’all know how it turns out.

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  • Debuging VBScript in Visual Studios Express

    - by Wil
    I have read around the net that its possible to debug VBScript WSH files Visual Studios 2005 Express (I think Web Edition) but everytime I try cscript.exe myscript.vbs //X the script just executes. I have tried VS Express 2005, 2008 and 2010 all editions. I have also tried Visual Studios Premium 2010 which does infact debug scripts as I would expect however I want to be able to debug scripts with free tools (I don't want to get a VS 2010 licence for all the other people on my team). I know about Microsoft Script Debugger but it doesn't let you discover objects as well as Visual studios does.

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  • The way I think about Diagnostic tools

    - by Daniel Moth
    Every software has issues, or as we like to call them "bugs". That is not a discussion point, just a mere fact. It follows that an important skill for developers is to be able to diagnose issues in their code. Of course we need to advance our tools and techniques so we can prevent bugs getting into the code (e.g. unit testing), but beyond designing great software, diagnosing bugs is an equally important skill. To diagnose issues, the most important assets are good techniques, skill, experience, and maybe talent. What also helps is having good diagnostic tools and what helps further is knowing all the features that they offer and how to use them. The following classification is how I like to think of diagnostics. Note that like with any attempt to bucketize anything, you run into overlapping areas and blurry lines. Nevertheless, I will continue sharing my generalizations ;-) It is important to identify at the outset if you are dealing with a performance or a correctness issue. If you have a performance issue, use a profiler. I hear people saying "I am using the debugger to debug a performance issue", and that is fine, but do know that a dedicated profiler is the tool for that job. Just because you don't need them all the time and typically they cost more plus you are not as familiar with them as you are with the debugger, doesn't mean you shouldn't invest in one and instead try to exclusively use the wrong tool for the job. Visual Studio has a profiler and a concurrency visualizer (for profiling multi-threaded apps). If you have a correctness issue, then you have several options - that's next :-) This is how I think of identifying a correctness issue Do you want a tool to find the issue for you at design time? The compiler is such a tool - it gives you an exact list of errors. Compilers now also offer warnings, which is their way of saying "this may be an error, but I am not smart enough to know for sure". There are also static analysis tools, which go a step further than the compiler in identifying issues in your code, sometimes with the aid of code annotations and other times just by pointing them at your raw source. An example is FxCop and much more in Visual Studio 11 Code Analysis. Do you want a tool to find the issue for you with code execution? Just like static tools, there are also dynamic analysis tools that instead of statically analyzing your code, they analyze what your code does dynamically at runtime. Whether you have to setup some unit tests to invoke your code at runtime, or have to manually run your app (and interact with it) under the tool, or have to use a script to execute your binary under the tool… that varies. The result is still a list of issues for you to address after the analysis is complete or a pause of the execution when the first issue is encountered. If a code path was not taken, no analysis for it will exist, obviously. An example is the GPU Race detection tool that I'll be talking about on the C++ AMP team blog. Another example is the MSR concurrency CHESS tool. Do you want you to find the issue at design time using a tool? Perform a code walkthrough on your own or with colleagues. There are code review tools that go beyond just diffing sources, and they help you with that aspect too. For example, there is a new one in Visual Studio 11 and searching with my favorite search engine yielded this article based on the Developer Preview. Do you want you to find the issue with code execution? Use a debugger - let’s break this down further next. This is how I think of debugging: There is post mortem debugging. That means your code has executed and you did something in order to examine what happened during its execution. This can vary from manual printf and other tracing statements to trace events (e.g. ETW) to taking dumps. In all cases, you are left with some artifact that you examine after the fact (after code execution) to discern what took place hoping it will help you find the bug. Learn how to debug dump files in Visual Studio. There is live debugging. I will elaborate on this in a separate post, but this is where you inspect the state of your program during its execution, and try to find what the problem is. More from me in a separate post on live debugging. There is a hybrid of live plus post-mortem debugging. This is for example what tools like IntelliTrace offer. If you are a tools vendor interested in the diagnostics space, it helps to understand where in the above classification your tool excels, where its primary strength is, so you can market it as such. Then it helps to see which of the other areas above your tool touches on, and how you can make it even better there. Finally, see what areas your tool doesn't help at all with, and evaluate whether it should or continue to stay clear. Even though the classification helps us think about this space, the reality is that the best tools are either extremely excellent in only one of this areas, or more often very good across a number of them. Another approach is to offer a toolset covering all areas, with appropriate integration and hand off points from one to the other. Anyway, with that brain dump out of the way, in follow-up posts I will dive into live debugging, and specifically live debugging in Visual Studio - stay tuned if that interests you. Comments about this post by Daniel Moth welcome at the original blog.

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  • Class Loading Deadlocks

    - by tomas.nilsson
    Mattis follows up on his previous post with one more expose on Class Loading Deadlocks As I wrote in a previous post, the class loading mechanism in Java is very powerful. There are many advanced techniques you can use, and when used wrongly you can get into all sorts of trouble. But one of the sneakiest deadlocks you can run into when it comes to class loading doesn't require any home made class loaders or anything. All you need is classes depending on each other, and some bad luck. First of all, here are some basic facts about class loading: 1) If a thread needs to use a class that is not yet loaded, it will try to load that class 2) If another thread is already loading the class, the first thread will wait for the other thread to finish the loading 3) During the loading of a class, one thing that happens is that the <clinit method of a class is being run 4) The <clinit method initializes all static fields, and runs any static blocks in the class. Take the following class for example: class Foo { static Bar bar = new Bar(); static { System.out.println("Loading Foo"); } } The first time a thread needs to use the Foo class, the class will be initialized. The <clinit method will run, creating a new Bar object and printing "Loading Foo" But what happens if the Bar object has never been used before either? Well, then we will need to load that class as well, calling the Bar <clinit method as we go. Can you start to see the potential problem here? A hint is in fact #2 above. What if another thread is currently loading class Bar? The thread loading class Foo will have to wait for that thread to finish loading. But what happens if the <clinit method of class Bar tries to initialize a Foo object? That thread will have to wait for the first thread, and there we have the deadlock. Thread one is waiting for thread two to initialize class Bar, thread two is waiting for thread one to initialize class Foo. All that is needed for a class loading deadlock is static cross dependencies between two classes (and a multi threaded environment): class Foo { static Bar b = new Bar(); } class Bar { static Foo f = new Foo(); } If two threads cause these classes to be loaded at exactly the same time, we will have a deadlock. So, how do you avoid this? Well, one way is of course to not have these circular (static) dependencies. On the other hand, it can be very hard to detect these, and sometimes your design may depend on it. What you can do in that case is to make sure that the classes are first loaded single threadedly, for example during an initialization phase of your application. The following program shows this kind of deadlock. To help bad luck on the way, I added a one second sleep in the static block of the classes to trigger the unlucky timing. Notice that if you uncomment the "//Foo f = new Foo();" line in the main method, the class will be loaded single threadedly, and the program will terminate as it should. public class ClassLoadingDeadlock { // Start two threads. The first will instansiate a Foo object, // the second one will instansiate a Bar object. public static void main(String[] arg) { // Uncomment next line to stop the deadlock // Foo f = new Foo(); new Thread(new FooUser()).start(); new Thread(new BarUser()).start(); } } class FooUser implements Runnable { public void run() { System.out.println("FooUser causing class Foo to be loaded"); Foo f = new Foo(); System.out.println("FooUser done"); } } class BarUser implements Runnable { public void run() { System.out.println("BarUser causing class Bar to be loaded"); Bar b = new Bar(); System.out.println("BarUser done"); } } class Foo { static { // We are deadlock prone even without this sleep... // The sleep just makes us more deterministic try { Thread.sleep(1000); } catch(InterruptedException e) {} } static Bar b = new Bar(); } class Bar { static { try { Thread.sleep(1000); } catch(InterruptedException e) {} } static Foo f = new Foo(); }

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  • Cocoa Memory Usage

    - by user288024
    I'm trying to track down some peculiar memory behavior in my Cocoa desktop app. My app does a lot of image processing using NSImage and uploads those images to a website over HTTP using NSURLConnection. After uploading several hundred images (some very large), when I run Instrument I get no leaks. I've also run through MallocDebug and get no leaks. When I dig into object allocations using Instrument I get output like this: GeneralBlock-9437184, Net Bytes 9437184, # Net 1 GeneralBlock-192512, Net Bytes 2695168, # Net 14 and etc., for smaller sizes. When I look at these in detail, they're marked as being owned by 'Foundation' and created via NSConcreteMutableData initWithCapacity. During HTTP upload I'm creating a post body using NSMutableData, so I'm guessing these are buffers Cocoa is caching for me when I create the NSMutableData objects. Is there a way to force Cocoa to free these? I'm 90% positive I'm releasing correctly (and Instruments and MallocDebug seem to confirm this), but I think Cocoa is keeping these around for perf reasons since I'm allocating so many MSMutableData buffers.

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  • Database change management tools?

    - by zodeus
    We are currently in the process of solidifying a database change management process. We run MySql 5 running on RedHat 5. I have selected LiquiBase as the tool because it's open source and allows us to expand its functionality later if needed. It also seems to be one of the few free projects that are still active. Has anyone here had any experience using LiquiBase or other Db versioning tools? Company Background: We are an SaaS company providing a 7/24 hosted application. There are dozens of instances running different versions of the same database and we need a way to manage the deploy process as it's starting to get out of control. The databases have hundreds of tables and we typically do releases once every 3 months.

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  • Is there anything RAD comparable to VCL?

    - by mawg
    After years in embedded programming, I have to develop a Windows app. I dug out my old C++ Builder and Delphi. These are great and the latest version costs over $1k, so I won't be going there. What I prarticularly like is the VCL (visual component library) which let's me code my own components and share them with others, plus the thousands of existing 3rd party components. I noticed that there is now also a RAD PHP from Borland too. I realzie that MSVC, QT, NetBeans, etc are good enough IDEs for RAD, BUT does anything offer the ease of the Borland products for developing additional components - and does anything else have thousands to choose from? PC based? Cross-platform is good. Browser based? Free is always good ;-) I don't particularly care about the programming language.

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  • Split textarea content into two at maxlength and flow excedant content in another textarea

    - by user1057339
    Wondering if its possible to create a short simple and sweet cross-browser jQuery (1.6) function that would split #textarea1 content into two by preserving the characters that amount to less than its var maxlength limit and transfering the remaining characters that exceed its maxlength limit in #textarea2. #textarea1 can push excedant in #textarea2, but if #textarea1 contains less than the maxlength limit, by default it wont get filled up with #textarea2 content, but you would have the option programatically to override this. I am just beginning to scratch the surface of jQuery but I noticed that this simple javascript can nearly do the trick, minus the free-flowing character movement. Scratching my head on this one. Thx a heap for any help. DC

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  • CodePlex Daily Summary for Tuesday, June 28, 2011

    CodePlex Daily Summary for Tuesday, June 28, 2011Popular ReleasesCoding4Fun Tools: Coding4Fun.Phone.Toolkit v1.4.3: Fix for prompts not returning the appbarMosaic Project: Mosaic Alpha build 261: - Fixed crash when pinning applications in x64 OS - Added Hub to video widget. It shows videos from Video library (only .wmv and .avi). Can work slow if there are too much files. - Fixed some issues with scrolling - Fixed bug with html widgets - Fixed bug in Gmail widget - Added html today widget missed in previous release - Now Mosaic saves running widgets if you restarting from optionsEnhSim: EnhSim 2.4.9 BETA: 2.4.9 BETAThis release supports WoW patch 4.2 at level 85 To use this release, you must have the Microsoft Visual C++ 2010 Redistributable Package installed. This can be downloaded from http://www.microsoft.com/downloads/en/details.aspx?FamilyID=A7B7A05E-6DE6-4D3A-A423-37BF0912DB84 To use the GUI you must have the .NET 4.0 Framework installed. This can be downloaded from http://www.microsoft.com/downloads/en/details.aspx?FamilyID=9cfb2d51-5ff4-4491-b0e5-b386f32c0992 - Added in some of th....NET Reflector Add-Ins: Reflector V7 Add-Ins: All the add-ins compiled for Reflector V7TerrariViewer: TerrariViewer v4.1 [4.0 Bug Fixes]: Version 4.1 ChangelogChanged how users will Open Player files (This change makes it much easier) This allowed me to remove the "Current player file" labels that were present Changed file control icons Added submit bug button Various Bug Fixes Fixed crashes related to clicking on buffs before a character is loaded Fixed crashes related to selecting "No Buff" when choosing a new buff Fixed crashes related to clicking on a "Max" button on the buff tab before a character is loaded Cor...AcDown????? - Anime&Comic Downloader: AcDown????? v3.0 Beta8: ??AcDown???????????????,?????????????????????。????????????????????,??Acfun、Bilibili、???、???、?????,???????????、???????。 AcDown???????????????????????????,???,???????????????????。 AcDown???????C#??,?????"Acfun?????"。 ????32??64? Windows XP/Vista/7 ????????????? ??:????????Windows XP???,?????????.NET Framework 2.0???(x86)?.NET Framework 2.0???(x64),?????"?????????"??? ??????????????,??????????: ??"AcDown?????"????????? ??v3.0 Beta8 ?? ??????????????? ???????????????(??????????) ???????...BlogEngine.NET: BlogEngine.NET 2.5: Get DotNetBlogEngine for 3 Months Free! Click Here for More Info 3 Months FREE – BlogEngine.NET Hosting – Click Here! If you want to set up and start using BlogEngine.NET right away, you should download the Web project. If you want to extend or modify BlogEngine.NET, you should download the source code. If you are upgrading from a previous version of BlogEngine.NET, please take a look at the Upgrading to BlogEngine.NET 2.5 instructions. To get started, be sure to check out our installatio...PHP Manager for IIS: PHP Manager 1.2 for IIS 7: This release contains all the functionality available in 62183 plus the following additions: Command Line Support via PowerShell - now it is possible to manage and script PHP installations on IIS by using Windows PowerShell. More information is available at Managing PHP installations with PHP Manager command line. Detection and alert when using local PHP handler - if a web site or a directory has a local copy of PHP handler mapping then the configuration changes made on upper configuration ...MiniTwitter: 1.71: MiniTwitter 1.71 ???? ?? OAuth ???????????? ????????、??????????????????? ???????????????????????SizeOnDisk: 1.0.10.0: Fix: issue 327: size format error when save settings Fix: some UI bindings trouble (sorting, refresh) Fix: user settings file deletion when corrupted Feature: TreeView virtualization (better speed with many folders) Feature: New file type DataGrid column Feature: In KByte view, show size of file < 1024B and > 0 with 3 decimal Feature: New language: Italian Task: Cleanup for speedRawr: Rawr 4.2.0: This is the Downloadable WPF version of Rawr!For web-based version see http://elitistjerks.com/rawr.php You can find the version notes at: http://rawr.codeplex.com/wikipage?title=VersionNotes Rawr AddonWe now have a Rawr Official Addon for in-game exporting and importing of character data hosted on Curse. The Addon does not perform calculations like Rawr, it simply shows your exported Rawr data in wow tooltips and lets you export your character to Rawr (including bag and bank items) like Char...HD-Trailers.NET Downloader: HD-Trailer.net Downloader 1.86: This version implements a new config flag "ConsiderTheatricalandNumberedTrailersasIdentical" that for the purposes of Exclusions only Teaser Trailer and one Trailer (named Trailer, Theatrical Traler Trailer No. 1, Trailer 1, Trailer No. 2, etc) will be downloaded. This also includes a bug fix where the .nfo file did not include the -trailer if configured for XBMC.N2 CMS: 2.2: * Web platform installer support available ** Nuget support available What's newDinamico Templates (beta) - an MVC3 & Razor based template pack using the template-first! development paradigm Boilerplate CSS & HTML5 Advanced theming with css comipilation (concrete, dark, roadwork, terracotta) Template-first! development style Content, news, listing, slider, image sizes, search, sitemap, globalization, youtube, google map Display Tokens - replaces text tokens with rendered content (usag...Circuit Diagram: Circuit Diagram v0.5 Beta: New in this release: New components: Ammeter (meter) Voltmeter (meter) Undo/redo functionality for placing/moving components Choose resolution when exporting PNG image New logoMicrosoft Ajax Minifier: Microsoft Ajax Minifier 4.23: XML input file can now specify both JS and CSS output files in the same XML file. Don't output octal escsape sequences in string literals for strict-mode scripts. Expand expression optimizations to handle more instances of logical-not being smaller. Properly handle comments that look like conditional comments but aren't because no @cc_on statement has been encountered. CSS Important comments should start on a new line, and CSS hacks should not have the ! in them. Various other smaller updates.KinectNUI: Jun 25 Alpha Release: Initial public version. No installer needed, just run the EXE.Terraria World Viewer: Version 1.5: Update June 24th Made compatible with the new tiles found in Terraria 1.0.5Kinect Earth Move: KinectEarthMove sample code: Sample code releasedThis is a sample code for Kinect for Windows SDK beta, which was demonstrated on Channel 9 Kinect for Windows SKD beta launch event on June 17 2011. Using color image and skeleton data from Kinect and user in front of Kinect can manipulate the earth between his/her hands.patterns & practices: Project Silk: Project Silk Community Drop 12 - June 22, 2011: Changes from previous drop: Minor code changes. New "Introduction" chapter. New "Modularity" chapter. Updated "Architecture" chapter. Updated "Server-Side Implementation" chapter. Updated "Client Data Management and Caching" chapter. Guidance Chapters Ready for Review The Word documents for the chapters are included with the source code in addition to the CHM to help you provide feedback. The PDF is provided as a separate download for your convenience. Installation Overview To ins...DotNetNuke® Community Edition: 06.00.00 Beta: Beta 1 (Build 2300) includes many important enhancements to the user experience. The control panel has been updated for easier access to the most important features and additional forms have been adapted to the new pattern. This release also includes many bug fixes that make it more stable than previous CTP releases. Beta ForumsNew ProjectsAI4CAD-3D: AI4CAD-3D bir 3 boyutlu tasarim ve ince ve kaba insaat metraj programidir.Beginner 2D game Dev -MokoNa: learning to make 2D games from ground up cae2rampage: A top down XNA-based multipalyer game.CamelWiki: Simple wiki software written in Perl using POD as markup language. CamelWiki can use MySQL, PostgreSQL or SQLite as database backend. DmPoster: An assistant to help us to post danmaku to bilibili.tv website. ????? bilibili.tv ?????????。 It's developed in C#. ????? C#。EasyDP: EasyDP is an open source Silverlight application to upload and manage one's display pictures in a website. It can be integrated to websites not limited to ASP.NET. It posts images up with generic HTTP form data thus it can communicate with HTTP handler written in any server-side programming language.E-Commerce TCP: Projeto E-Commerce para a cadeira de TCP da UFRGS. Semestre 01/2011.Encounter: a host-guest interaction energy calculator: Encounter is a simple program for calculating the interaction energy between two molecules using the output from a GAUSSIAN two-component counterpoise correction calculation. The Counterpoise Correction arises due to the Basis Set Superposition Error in quantum modeling.Excel add-in for regular expressions: Match, replace, and search character strings in Excel using the C++0x <regex> library.FlvBugger: ?Flv????????,???????????????????,????????。Frontdesk: Frontdesk is a form creator and autoresponder program designed in Microsoft ASP.NET MVC 2. It contains a custom member/security implementation, admin area, and lots of flexibility in form & autoresponder creation. It uses an integrated WYSIWYG editor & form field drag-and-drop.His2012: his2012ixbShop: ???????? Open-source e-commerce platformJBot: PL: Program sieciowy JBot jest chatterbotem. EN: Network program JBot is chatterbot.JungleSoft_Lux: luxKillstone PaRSS: Killstone PaRSS is a jQuery Plugin that parses an RSS feed and appends the items from the feed to a UL or OL on your webpage.Killstone PHP Framework: A simple PHP framework that helps organize your PHP application in a Model / View / Controller pattern.Orchard-PhotoTag-FamilyTree: This is an Orchard Module that allows you to tag a photo. It comes with a widget and a Page type. In addition to tagging photo's you can create a family tree/org chart to drill down into. (I originally built this for a family reunion).ResX DSL: ResX DSL is a Domain Specific Language created with Visual Studio DSL Tools. It helps to define a ResX DSL-Model with multi-language and multi-typed Ressources and generates with T4-Templates an ordinary Resx-File as well as a Proxy-Class with a given Ressources-Set.Self-Tracking Entity Generator for WPF and Silverlight: An Entity Framework project item to generate self-tracking entity classes for WPF and Silverlight applications.SharePoint 2010 Print List Ribbon Button: SharePoint 2010 Print List button on Top Ribbon for Calendar listStocks Application: This is technical demo to apply F-Sharp (F#) language in real world application. This application is close to real world enterprise application (with very optimal solutions, at least in 2011). The function of this application is to get Stock Quote Data and Historical Stock Prices from Yahoo Finance The Smart Shopping List: The Smart Shopping List makes it easier to keep track of your purchasesUmbraco Flickr API Search - XSLT Extension: An Umbraco XSLT Extension Package that enables calling the Flickr API to retrieve photos from a tag(s), user, group, and text search. The underlying engine is built off of the FlickrNET library (http://www.codeplex.com/FlickrNet).WASTLib: WASTLib is the acronim of Web Application Security Testing Library. Its main purpose is to easly create security tests for your web application. WinPanel: WinPanel ist ein nachgemachtes GNOME-Panel, dass auf Windows läuft. Es wird in Visual Basic 2010 Express programmiert.

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  • Weekend With #iPad

    - by andrewbrust
    Saturday morning, I got up, got dressed and took a 7-minute walk up to the Apple Store in New York’s Meatpacking District to pick up my reserved iPad.  This precinct, which borders Greenwich Village (where I live and grew up) was, when I was a kid, a very industrial and smelly neighborhood during the day  and a rough neighborhood at night.  So imagine my sense of irony as I walked up Hudson Street towards 14th Street, to go wait in line with a bunch of hipsters to buy an iPad on launch day. Numerous blue T-shirt-clad Apple store workers were on hand to check people in to the line specifically identified for people who had reserved an iPad.  Others workers passed out water and all of them, I kid you not, applauded people as they got their chance to go into the store and buy their devices.  They also cheered people and yelled “congratulations” as they left.  The event had all the charm of a mass wedding officiated by Reverend Sung Myung Moon.  Once inside, a nice dude named Trey, with lots of tattoos on his calves, helped me and I acquired my device in short order.  Another guy helped me activate the device, which was comical, because that has to be done through iTunes, which I hadn’t logged into in a while. Turns out my user id was my email address from the company I sold 5 1/2 years ago.  Who knew?  Regardless, I go the device working, packed up and left the store, shuddering as I was cheered and congratulated.  By this time (about 10:30am) the line for reserved units and even walk-ins, was gone.  The iPhone launch this was not. As much as I detested the Apple Store experience, I must say the device is really nice.  the screen is bright, the colors are bold, and the experience is ultra-smooth.  I quickly tested Safari, YouTube, Google Maps, and then installed a few apps, including the New York Times Editors’ Choice and a couple of Twitter clients. Some initial raves: Google Maps and Street View on the iPad is just amazing.  The screen is full-size like a PC or Mac, but it’s right in front of you and responding to taps and flicks and pinches and it’s really engulfing.  Video and photos are really nice on this device, despite the fact that 16:9 and anamorphic aspect ration content is letter boxed.  It still looks amazing.  And apps that are designed especially for the iPad, including The Weather Channel and Gilt and Kayak just look stunning.  The richness, the friendly layout, the finger-friendly UIs, and the satisfaction of not having a keyboard between you and the information you’re managing, while you sit on a couch or an easy chair, is just really a beautiful thing.  The mere experience of seeing these apps’ splash screens causes a shiver and Goosebumps.  Truly.  The iPad is not a desktop machine, and it’s not pocket device.  That doesn’t mean it’s useless though.  It’s the perfect “couchtop” computer. Now some downsides: the WiFi radio seems a bit flakey.  More than a few times, I have had to toggle the WiFi off and back on to get it to connect properly.  Worse yet, the iPad is totally bamboozled by the fact that I have four WiFi access points in my house, each with the same SSID.  My laptops are smart enough to roam from one to the other, but the iPad seems to maintain an affinity for the downstairs access point, even if I’m turning it on two flights up.  Telling the iPad to “forget” my WiFi network and then re-associate with it doesn’t help. More downers: as you might expect, there are far more applications developed for the iPhone than the iPad.  And although iPhone apps run on the iPad, that provides about the same experience as watching standard def on a big HD flat panel, complete with the lousy choice of thick black borders or zooming the picture in to fill the screen.  And speaking of iPhone Apps, I can’t get the Sonos one to work.  Ideally, they’d have a dedicated iPad app and it would work on the first try.  And the iPad is just as bad as any netbook when it comes to being a magnet for fingerprints.  The lack of multi-tasking is quite painful too – truly, I don’t mind if only one app can be active at once, but the lack of ability to switch between apps, and the requirement to return to the home screen and re-launch a previous app to switch back, is already old and I’ve had the thing less than 48 hours. These are just initial impressions.  I’ll have a fuller analysis soon, after I’ve had some more break-in time with my new toy.  I’ll be thinking not just about the iPad and iPhone but also about Android, the 2.1 update for which was pushed to my Droid today, and Windows Phone 7, whose “hub” concept I now understand the value of.  This has been a great year for alternative computing devices, and I see no net downside for Apple, Google or Microsoft.  Exciting times.

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  • Flow-Design Cheat Sheet &ndash; Part I, Notation

    - by Ralf Westphal
    You want to avoid the pitfalls of object oriented design? Then this is the right place to start. Use Flow-Oriented Analysis (FOA) and –Design (FOD or just FD for Flow-Design) to understand a problem domain and design a software solution. Flow-Orientation as described here is related to Flow-Based Programming, Event-Based Programming, Business Process Modelling, and even Event-Driven Architectures. But even though “thinking in flows” is not new, I found it helpful to deviate from those precursors for several reasons. Some aim at too big systems for the average programmer, some are concerned with only asynchronous processing, some are even not very much concerned with programming at all. What I was looking for was a design method to help in software projects of any size, be they large or tiny, involing synchronous or asynchronous processing, being local or distributed, running on the web or on the desktop or on a smartphone. That´s why I took ideas from all of the above sources and some additional and came up with Event-Based Components which later got repositioned and renamed to Flow-Design. In the meantime this has generated some discussion (in the German developer community) and several teams have started to work with Flow-Design. Also I´ve conducted quite some trainings using Flow-Orientation for design. The results are very promising. Developers find it much easier to design software using Flow-Orientation than OOAD-based object orientation. Since Flow-Orientation is moving fast and is not covered completely by a single source like a book, demand has increased for at least an overview of the current state of its notation. This page is trying to answer this demand by briefly introducing/describing every notational element as well as their translation into C# source code. Take this as a cheat sheet to put next to your whiteboard when designing software. However, please do not expect any explanation as to the reasons behind Flow-Design elements. Details on why Flow-Design at all and why in this specific way you´ll find in the literature covering the topic. Here´s a resource page on Flow-Design/Event-Based Components, if you´re able to read German. Notation Connected Functional Units The basic element of any FOD are functional units (FU): Think of FUs as some kind of software code block processing data. For the moment forget about classes, methods, “components”, assemblies or whatever. See a FU as an abstract piece of code. Software then consists of just collaborating FUs. I´m using circles/ellipses to draw FUs. But if you like, use rectangles. Whatever suites your whiteboard needs best.   The purpose of FUs is to process input and produce output. FUs are transformational. However, FUs are not called and do not call other FUs. There is no dependency between FUs. Data just flows into a FU (input) and out of it (output). From where and where to is of no concern to a FU.   This way FUs can be concatenated in arbitrary ways:   Each FU can accept input from many sources and produce output for many sinks:   Flows Connected FUs form a flow with a start and an end. Data is entering a flow at a source, and it´s leaving it through a sink. Think of sources and sinks as special FUs which conntect wires to the environment of a network of FUs.   Wiring Details Data is flowing into/out of FUs through wires. This is to allude to electrical engineering which since long has been working with composable parts. Wires are attached to FUs usings pins. They are the entry/exit points for the data flowing along the wires. Input-/output pins currently need not be drawn explicitly. This is to keep designing on a whiteboard simple and quick.   Data flowing is of some type, so wires have a type attached to them. And pins have names. If there is only one input pin and output pin on a FU, though, you don´t need to mention them. The default is Process for a single input pin, and Result for a single output pin. But you´re free to give even single pins different names.   There is a shortcut in use to address a certain pin on a destination FU:   The type of the wire is put in parantheses for two reasons. 1. This way a “no-type” wire can be easily denoted, 2. this is a natural way to describe tuples of data.   To describe how much data is flowing, a star can be put next to the wire type:   Nesting – Boards and Parts If more than 5 to 10 FUs need to be put in a flow a FD starts to become hard to understand. To keep diagrams clutter free they can be nested. You can turn any FU into a flow: This leads to Flow-Designs with different levels of abstraction. A in the above illustration is a high level functional unit, A.1 and A.2 are lower level functional units. One of the purposes of Flow-Design is to be able to describe systems on different levels of abstraction and thus make it easier to understand them. Humans use abstraction/decomposition to get a grip on complexity. Flow-Design strives to support this and make levels of abstraction first class citizens for programming. You can read the above illustration like this: Functional units A.1 and A.2 detail what A is supposed to do. The whole of A´s responsibility is decomposed into smaller responsibilities A.1 and A.2. FU A thus does not do anything itself anymore! All A is responsible for is actually accomplished by the collaboration between A.1 and A.2. Since A now is not doing anything anymore except containing A.1 and A.2 functional units are devided into two categories: boards and parts. Boards are just containing other functional units; their sole responsibility is to wire them up. A is a board. Boards thus depend on the functional units nested within them. This dependency is not of a functional nature, though. Boards are not dependent on services provided by nested functional units. They are just concerned with their interface to be able to plug them together. Parts are the workhorses of flows. They contain the real domain logic. They actually transform input into output. However, they do not depend on other functional units. Please note the usage of source and sink in boards. They correspond to input-pins and output-pins of the board.   Implicit Dependencies Nesting functional units leads to a dependency tree. Boards depend on nested functional units, they are the inner nodes of the tree. Parts are independent, they are the leafs: Even though dependencies are the bane of software development, Flow-Design does not usually draw these dependencies. They are implicitly created by visually nesting functional units. And they are harmless. Boards are so simple in their functionality, they are little affected by changes in functional units they are depending on. But functional units are implicitly dependent on more than nested functional units. They are also dependent on the data types of the wires attached to them: This is also natural and thus does not need to be made explicit. And it pertains mainly to parts being dependent. Since boards don´t do anything with regard to a problem domain, they don´t care much about data types. Their infrastructural purpose just needs types of input/output-pins to match.   Explicit Dependencies You could say, Flow-Orientation is about tackling complexity at its root cause: that´s dependencies. “Natural” dependencies are depicted naturally, i.e. implicitly. And whereever possible dependencies are not even created. Functional units don´t know their collaborators within a flow. This is core to Flow-Orientation. That makes for high composability of functional units. A part is as independent of other functional units as a motor is from the rest of the car. And a board is as dependend on nested functional units as a motor is on a spark plug or a crank shaft. With Flow-Design software development moves closer to how hardware is constructed. Implicit dependencies are not enough, though. Sometimes explicit dependencies make designs easier – as counterintuitive this might sound. So FD notation needs a ways to denote explicit dependencies: Data flows along wires. But data does not flow along dependency relations. Instead dependency relations represent service calls. Functional unit C is depending on/calling services on functional unit S. If you want to be more specific, name the services next to the dependency relation: Although you should try to stay clear of explicit dependencies, they are fundamentally ok. See them as a way to add another dimension to a flow. Usually the functionality of the independent FU (“Customer repository” above) is orthogonal to the domain of the flow it is referenced by. If you like emphasize this by using different shapes for dependent and independent FUs like above. Such dependencies can be used to link in resources like databases or shared in-memory state. FUs can not only produce output but also can have side effects. A common pattern for using such explizit dependencies is to hook a GUI into a flow as the source and/or the sink of data: Which can be shortened to: Treat FUs others depend on as boards (with a special non-FD API the dependent part is connected to), but do not embed them in a flow in the diagram they are depended upon.   Attributes of Functional Units Creation and usage of functional units can be modified with attributes. So far the following have shown to be helpful: Singleton: FUs are by default multitons. FUs in the same of different flows with the same name refer to the same functionality, but to different instances. Think of functional units as objects that get instanciated anew whereever they appear in a design. Sometimes though it´s helpful to reuse the same instance of a functional unit; this is always due to valuable state it holds. Signify this by annotating the FU with a “(S)”. Multiton: FUs on which others depend are singletons by default. This is, because they usually are introduced where shared state comes into play. If you want to change them to be a singletons mark them with a “(M)”. Configurable: Some parts need to be configured before the can do they work in a flow. Annotate them with a “(C)” to have them initialized before any data items to be processed by them arrive. Do not assume any order in which FUs are configured. How such configuration is happening is an implementation detail. Entry point: In each design there needs to be a single part where “it all starts”. That´s the entry point for all processing. It´s like Program.Main() in C# programs. Mark the entry point part with an “(E)”. Quite often this will be the GUI part. How the entry point is started is an implementation detail. Just consider it the first FU to start do its job.   Patterns / Standard Parts If more than a single wire is attached to an output-pin that´s called a split (or fork). The same data is flowing on all of the wires. Remember: Flow-Designs are synchronous by default. So a split does not mean data is processed in parallel afterwards. Processing still happens synchronously and thus one branch after another. Do not assume any specific order of the processing on the different branches after the split.   It is common to do a split and let only parts of the original data flow on through the branches. This effectively means a map is needed after a split. This map can be implicit or explicit.   Although FUs can have multiple input-pins it is preferrable in most cases to combine input data from different branches using an explicit join: The default output of a join is a tuple of its input values. The default behavior of a join is to output a value whenever a new input is received. However, to produce its first output a join needs an input for all its input-pins. Other join behaviors can be: reset all inputs after an output only produce output if data arrives on certain input-pins

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  • Suggestion for chkstk.asm stackoverfolw exception in C++ with Visual Studio 2010

    - by Gulshan
    I am working with an implementation of merge sort. I am doing C++ Visual Studio 2010. But when I took a array of 300000 integers for timing, it is showing an unhandled stackoverflow exception and taking me to a readonly file named "chkstk.asm". I reduced the size to 200000 and it worked. Again the same code worked with C-free 4 editor (mingw 2.95) without any problem while the size was 400000. Do you have any suggestion to get the code working in Visual Studio? May be the recursion in the mergesort is causing the problem.

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