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• vmdk to live cd - VMware vmxnet virtual NIC driver Kernel panic

  - by ronalchn

  Task I am trying to convert a virtual machine to a live CD. Specifically, the virtual machine I am trying to convert is the IOI 2013 Competition Environment. In this task, I am aided by a guide Converting a virtual disk image: VDI or VMDK to an ISO you can distribute. Symptoms However, after getting through all the instructions, the live CD causes a kernel panic on boot on bare metal. In particular, the screen shows: [0.737348] cdrom: Uniform CD-ROM driver Revision: 3.20 [0.737503] sr 3:0:0:0: >Attached scsi CD-ROM sr0 [0.737638] sr 3:0:0:0: >Attached scsi generic sg2 type 5 [0.737771] Freeing unused kernel memory: 756k freed [0.738093] Write protecting the kernel text: 5960k [0.738155] Write protecting the kernel read-only data: 2424k [0.738224] NX-protecting the kernel data: 4280k Loading, please wait... [0.752252] udevd[100]: starting version 175 [0.768708] VMware vmxnet3 virtual NIC driver - version 1.1.29.0-k-NAPI [0.781204] VMware PVSCSI driver - version 1.0.2.0-k [0.789555] VMware vmxnet virtual NIC driver [0.799356] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000200 [0.799356] [0.799472] Pid: 1, comm: init Tainted: G 0 3.5.0-17-generic #28-Ubuntu [0.799549] Call Trace: [0.799603] [<c15bf0ec>] panic+0x81/0x17b [0.799654] [<c104a6a5>] do_exit+0x745/0x7a0 [0.799707] [<c104a9a4>] do_group_exit+0x34/0xa0 [0.799760] [<c104aa28>] sys_exit_group+0x18/0x20 [0.799813] [<c15cff5f>] sysenter_do_call+0x12/0x28 Possible problem I suspect that the problem is the VMware vmxnet virtual NIC driver - however, I do not know how I can uninstall it, and possibly install one for a bare metal machine. If anyone knows which packages needs installing/uninstalling at the .rootfs/ chroot directory stage, please let me know. Details on procedure Do note that after importing the .ova file into Virtualbox, the virtual machine is stored as a .vmdk file already, and not a .vdi file. I would like to point out some results of the procedure followed in case of any questions. This is after extracting the filesystem from the .raw file to the .rootfs/ directory mentioned in the blog. I changed the filesystem table as mentioned in the blog, then looked at the possible "kernel optimized for virtualization". However, I found that linux-image-generic was already installed. Also, when running the command dpkg-query --showformat='${Package}\n' -W 'vmware-tools*' (or dpkg-query --showformat='${Package}\n' -W '*-virtual'), no packages were found. Thus, I did not find any virtualization specific packages. I proceeded to generate the iso following the steps in the blog, and burned it to a DVD.

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• MVC Portable Areas Enhancement &ndash; Embedded Resource Controller

  - by Steve Michelotti

  MvcContrib contains a feature called Portable Areas which I’ve recently blogged about. In short, portable areas provide a way to distribute MVC binary components as simple .NET assemblies where the aspx/ascx files are actually compiled into the assembly as embedded resources. This is an extremely cool feature but once you start building robust portable areas, you’ll also want to be able to access other external files like css and javascript.  After my recent post suggesting portable areas be expanded to include other embedded resources, Eric Hexter asked me if I’d like to contribute the code to MvcContrib (which of course I did!). Embedded resources are stored in a case-sensitive way in .NET assemblies and the existing embedded view engine inside MvcContrib already took this into account. Obviously, we’d want the same case sensitivity handling to be taken into account for any embedded resource so my job consisted of 1) adding the Embedded Resource Controller, and 2) a little refactor to extract the logic that deals with embedded resources so that the embedded view engine and the embedded resource controller could both leverage it and, therefore, keep the code DRY. The embedded resource controller targets these scenarios: External image files that are referenced in an <img> tag External files referenced like css or JavaScript files Image files referenced inside css files Embedded Resources Walkthrough This post will describe a walkthrough of using the embedded resource controller in your portable areas to include the scenarios outlined above. I will build a trivial “Quick Links” widget to illustrate the concepts. The portable area registration is the starting point for all portable areas. The MvcContrib.PortableAreas.EmbeddedResourceController is optional functionality – you must opt-in if you want to use it.  To do this, you simply “register” it by providing a route in your area registration that uses it like this: 1: context.MapRoute("ResourceRoute", "quicklinks/resource/{resourceName}", 2: new { controller = "EmbeddedResource", action = "Index" }, 3: new string[] { "MvcContrib.PortableAreas" }); First, notice that I can specify any route I want (e.g., “quicklinks/resources/…”).  Second, notice that I need to include the “MvcContrib.PortableAreas” namespace as the fourth parameter so that the framework is able to find the EmbeddedResourceController at runtime. The handling of embedded views and embedded resources have now been merged.  Therefore, the call to: 1: RegisterTheViewsInTheEmmeddedViewEngine(GetType()); has now been removed (breaking change).  It has been replaced with: 1: RegisterAreaEmbeddedResources(); Other than that, the portable area registration remains unchanged. The solution structure for the static files in my portable area looks like this: I’ve got a css file in a folder called “Content” as well as a couple of image files in a folder called “images”. To reference these in my aspx/ascx code, all of have to do is this: 1: <link href="<%= Url.Resource("Content.QuickLinks.css") %>" rel="stylesheet" type="text/css" /> 2: <img src="<%= Url.Resource("images.globe.png") %>" /> This results in the following HTML mark up: 1: <link href="/quicklinks/resource/Content.QuickLinks.css" rel="stylesheet" type="text/css" /> 2: <img src="/quicklinks/resource/images.globe.png" /> The Url.Resource() method is now included in MvcContrib as well. Make sure you import the “MvcContrib” namespace in your views. Next, I have to following html to render the quick links: 1: <ul class="links"> 2: <li><a href="http://www.google.com">Google</a></li> 3: <li><a href="http://www.bing.com">Bing</a></li> 4: <li><a href="http://www.yahoo.com">Yahoo</a></li> 5: </ul> Notice the <ul> tag has a class called “links”. This is defined inside my QuickLinks.css file and looks like this: 1: ul.links li 2: { 3: background: url(/quicklinks/resource/images.navigation.png) left 4px no-repeat; 4: padding-left: 20px; 5: margin-bottom: 4px; 6: } On line 3 we’re able to refer to the url for the background property. As a final note, although we already have complete control over the location of the embedded resources inside the assembly, what if we also want control over the physical URL routes as well. This point was raised by John Nelson in this post. This has been taken into account as well. For example, suppose you want your physical url to look like this: 1: <img src="/quicklinks/images/globe.png" /> instead of the same corresponding URL shown above (i.e., “/quicklinks/resources/images.globe.png”). You can do this easily by specifying another route for it which includes a “resourcePath” parameter that is pre-pended. Here is the complete code for the area registration with the custom route for the images shown on lines 9-11: 1: public class QuickLinksRegistration : PortableAreaRegistration 2: { 3: public override void RegisterArea(System.Web.Mvc.AreaRegistrationContext context, IApplicationBus bus) 4: { 5: context.MapRoute("ResourceRoute", "quicklinks/resource/{resourceName}", 6: new { controller = "EmbeddedResource", action = "Index" }, 7: new string[] { "MvcContrib.PortableAreas" }); 8:   9: context.MapRoute("ResourceImageRoute", "quicklinks/images/{resourceName}", 10: new { controller = "EmbeddedResource", action = "Index", resourcePath = "images" }, 11: new string[] { "MvcContrib.PortableAreas" }); 12:   13: context.MapRoute("quicklink", "quicklinks/{controller}/{action}", 14: new {controller = "links", action = "index"}); 15:   16: this.RegisterAreaEmbeddedResources(); 17: } 18:   19: public override string AreaName 20: { 21: get 22: { 23: return "QuickLinks"; 24: } 25: } 26: } The Quick Links portable area results in the following requests (including custom route formats): The complete code for this post is now included in the Portable Areas sample solution in the latest MvcContrib source code. You can get the latest code now.  Portable Areas open up exciting new possibilities for MVC development!

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• Seriously, It’s Time to Get Your Content Act Together

  - by Mike Stiles

  Branded content, content marketing, social content, brand journalism, we’re seeing those terms more and more. Why? The technology tools are coming together. We should know. We can gather big data, crunch it, listen to the public, moderate, respond, get to know the customer intimately, know what they like, know what they want, we can target, distribute, amplify, measure engagement and reaction, modify strategy and even automate a great deal of all that. An amazing machine, a sleek, smooth-running engine has been built such that all the parts can interact and work together to deliver peak performance and maximum output. But that engine isn’t going anywhere without any gas. Content is the gas. Yes, we curate other people’s content. We can siphon their gas. There’s tech to help with that too. But as for the creation of original, worthwhile content made for a specific audience, our audience, machines can’t do that…at least not yet. Curated content is great. But somebody has to originate the content for it to be curated and shared. And since the need for good, curated content is obviously large and the desire to share is there, it’s a winning proposition for a brand to be a consistent producer of original content. And yet, it feels like content is an issue we’re avoiding. There’s a reluctance to build a massive pipeline if you have no idea what you’re going to run through it. The C-suite often doesn’t know what content is, that it’s different from ads, where to get it, who makes it, how long it should be, what the point of it is if there’s no hard sell of the product, what it costs, how to use it, how to measure it, how to make sure it’s good, or how to make sure it will keep flowing. It could be the reason many brands aren’t pulling the trigger on socially enabling the enterprise. And that’s a shame, because there are a lot of creative, daring, experimental, uniquely talented entertainers and journalists chomping at the bit to execute content for brands. But for many corporate executives, content is “weird,” and the people who make it are even weirder. The content side of the equation is human. It’s art, but art that can be informed by data. The natural inclination is for brands to turn to their agencies for such creative endeavors. But agencies are falling into one of two categories. They’re failing to transition from ads to content. In “Content Era, What’s the Role of Agencies?” Alexander Jutkowitz says agencies were made for one-hit campaigns, not ongoing content. Or, they’re ready and capable but can’t get clients to do the right things. Agencies have to make money, even if it means continuing to do the wrong things because that’s all the client will agree to. So what we wind up with in the pipeline is advertising, marketing-heavy content, content that was obviously created or spearheaded by non-creative executives, random & inconsistent content, copy written for SEO bots, and other completely uninteresting nightmares. Frank Rose, author of “The Art of Immersion,” writes, “Content without story and excitement is noise pollution.” In the old days, you made an ad and inserted it into shows made by people who knew what they were doing. You could bask in that show’s success and leverage their audience. Now, you are tasked with attracting, amassing and holding your own audience. You may just want to make, advertise and sell your widgets. But now there’s a war on for a precious commodity, attention. People are busy. They have filters to keep uninteresting and irrelevant things out. They value their time and expect value back when they give it up. Joe Pulizzi, founder of the Content Marketing Institute, says, "Your customers don't care about you, your products, your services…they care about themselves, their wants and their needs." Is it worth getting serious about content and doing it right? 61% of consumers feel better about a company that delivers custom content (Custom Content Council). Interesting content is one of the top 3 reasons people follow brands on social (Content+). 78% of consumers think organizations that provide custom content want to build good relationships with them (TMG Custom Media). On the B2B side, 80% of business decision makers prefer to get company info in a series of articles vs. an ad. So what’s the hang-up? Cited barriers to content marketing are lack of human resources (42%) and lack of budget (35%). 54% of brands don’t have a single on-site, dedicated content creator. And only 38% of brands have a content marketing strategy. Tech has built the biggest, most incredible stage for brands that’s ever been built. Putting something on that stage is your responsibility. Do a bad show, or no show at all, and you’ll be the beautiful, talented actress that never got discovered. @mikestilesPhoto: Gabriella Fabbri, stock.xchng

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• Adopting DBVCS

  - by Wes McClure

  Identify early adopters Pick a small project with a small(ish) team.  This can be a legacy application or a green-field application. Strive to find a team of early adopters that will be eager to try something new. Get the team on board! Research Research the tool(s) that you want to use.  Some tools provide all of the features you would need while some only provide a slice of the pie.  DBVCS requires the ability to manage a set of change scripts that update a database from one version to the next.  Ideally a tool can track database versions and automatically apply updates.  The change script generation process can be manual, but having diff tools available to automatically generate it can really reduce the overhead to adoption.  Finally, an automated tool to generate a script file per database object is an added bonus as your version control system can quickly identify what was changed in a commit (add/del/modify), just like with code changes. Don’t settle on just one tool, identify several.  Then work with the team to evaluate the tools.  Have the team do some tests of the following scenarios with each tool: Baseline an existing database: can the migration tool work with legacy databases?  Caution: most migration platforms do not support baselines or have poor support, especially the fad of fluent APIs. Add/drop tables Add/drop procedures/functions/views Alter tables (rename columns, add columns, remove columns) Massage data – migrations sometimes involve changing data types that cannot be implicitly casted and require you to decide how the data is explicitly cast to the new type.  This is a requirement for a migrations platform.  Think about a case where you might want to combine fields, or move a field from one table to another, you wouldn’t want to lose the data. Run the tool via the command line.  If you cannot automate the tool in Continuous Integration what is the point? Create a copy of a database on demand. Backup/restore databases locally. Let the team give feedback and decide together, what tool they would like to try out. My recommendation at this point would be to include TSqlMigrations and RoundHouse as SQL based migration platforms.  In general I would recommend staying away from the fluent platforms as they often lack baseline capabilities and add overhead to learn a new API when SQL is already a very well known DSL.  Code migrations often get messy with procedures/views/functions as these have to be created with SQL and aren’t cross platform anyways.  IMO stick to SQL based migrations. Reconciling Production If your project is a legacy application, you will need to reconcile the current state of production with your development databases.  Find changes in production and bring them down to development, even if they are old and need to be removed.  Once complete, produce a baseline of either dev or prod as they are now in sync.  Commit this to your VCS of choice. Add whatever schema changes tracking mechanism your tool requires to your development database.  This often requires adding a table to track the schema version of that database.  Your tool should support doing this for you.  You can add this table to production when you do your next release. Script out any changes currently in dev.  Remove production artifacts that you brought down during reconciliation.  Add change scripts for any outstanding changes in dev since the last production release.  Commit these to your repository.   Say No to Shared Dev DBs Simply put, you wouldn’t dream of sharing a code checkout, why would you share a development database?  If you have a shared dev database, back it up, distribute the backups and take the shared version offline (including the dev db server once all projects are using DB VCS).  Doing DB VCS with a shared database is bound to cause problems as people won’t be able to easily script out their own changes from those that others are working on.   First prod release Copy prod to your beta/testing environment.  Add the schema changes table (or mechanism) and do a test run of your changes.  If successful you can schedule this to be run on production.   Evaluation After your first release, evaluate the pain points of the process.  Try to find tools or modifications to existing tools to help fix them.  Don’t leave stones unturned, iteratively evolve your tools and practices to make the process as seamless as possible.  This is why I suggest open source alternatives.  Nothing is set in stone, a good example was adding transactional support to TSqlMigrations.  We ran into situations where an update would break a database, so I added a feature to do transactional updates and rollback on errors!  Another good example is generating change scripts.  We have been manually making these for months now.  I found an open source project called Open DB Diff and integrated this with TSqlMigrations.  These were things we just accepted at the time when we began adopting our tool set.  Once we became comfortable with the base functionality, it was time to start automating more of the process.  Just like anything else with development, never be afraid to try to find tools to make your job easier!   Enjoy -Wes

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• Configure Oracle SOA JMSAdatper to Work with WLS JMS Topics

  - by fip

  The WebLogic JMS Topic are typically running in a WLS cluster. So as your SOA composites that receive these Topic messages. In some situation, the two clusters are the same while in others they are sepearate. The composites in SOA cluster are subscribers to the JMS Topic in WebLogic cluster. As nature of JMS Topic is meant to distribute the same copy of messages to all its subscribers, two questions arise immediately when it comes to load balancing the JMS Topic messages against the SOA composites: How to assure all of the SOA cluster members receive different messages instead of the same (duplicate) messages, even though the SOA cluster members are all subscribers to the Topic? How to make sure the messages are evenly distributed (load balanced) to SOA cluster members? Here we will walk through how to configure the JMS Topic, the JmsAdapter connection factory, as well as the composite so that the JMS Topic messages will be evenly distributed to same composite running off different SOA cluster nodes without causing duplication. 2. The typical configuration In this typical configuration, we achieve the load balancing of JMS Topic messages to JmsAdapters by configuring a partitioned distributed topic along with sharable subscriptions. You can reference the documentation for explanation of PDT. And this blog posting does a very good job to visually explain how this combination of configurations would message load balancing among clients of JMS Topics. Our job is to apply this configuration in the context of SOA JMS Adapters. To do so would involve the following steps: Step A. Configure JMS Topic to be UDD and PDT, at the WebLogic cluster that house the JMS Topic Step B. Configure JCA Connection Factory with proper ServerProperties at the SOA cluster Step C. Reference the JCA Connection Factory and define a durable subscriber name, at composite's JmsAdapter (or the *.jca file) Here are more details of each step: Step A. Configure JMS Topic to be UDD and PDT, You do this at the WebLogic cluster that house the JMS Topic. You can follow the instructions at Administration Console Online Help to create a Uniform Distributed Topic. If you use WebLogic Console, then at the same administration screen you can specify "Distribution Type" to be "Uniform", and the Forwarding policy to "Partitioned", which would make the JMS Topic Uniform Distributed Destination and a Partitioned Distributed Topic, respectively Step B: Configure ServerProperties of JCA Connection Factory You do this step at the SOA cluster. This step is to make the JmsAdapter that connect to the JMS Topic through this JCA Connection Factory as a certain type of "client". When you configure the JCA Connection Factory for the JmsAdapter, you define the list of properties in FactoryProperties field, in a semi colon separated list: ClientID=myClient;ClientIDPolicy=UNRESTRICTED;SubscriptionSharingPolicy=SHARABLE;TopicMessageDistributionAll=false You can refer to Chapter 8.4.10 Accessing Distributed Destinations (Queues and Topics) on the WebLogic Server JMS of the Adapter User Guide for the meaning of these properties. Please note: Except for ClientID, other properties such as the ClientIDPolicy=UNRESTRICTED, SubscriptionSharingPolicy=SHARABLE and TopicMessageDistributionAll=false are all default settings for the JmsAdapter's connection factory. Therefore you do NOT have to explicitly specify them explicitly. All you need to do is the specify the ClientID. The ClientID is different from the subscriber ID that we are to discuss in the later steps. To make it simple, you just need to remember you need to specify the client ID and make it unique per connection factory. Here is the example setting: Step C. Reference the JCA Connection Factory and define a durable subscriber name, at composite's JmsAdapter (or the *.jca file) In the following example, the value 'MySubscriberID-1' was given as the value of property 'DurableSubscriber': <adapter-config name="subscribe" adapter="JMS Adapter" wsdlLocation="subscribe.wsdl" xmlns="http://platform.integration.oracle/blocks/adapter/fw/metadata"> <connection-factory location="eis/wls/MyTestUDDTopic" UIJmsProvider="WLSJMS" UIConnectionName="ateam-hq24b"/> <endpoint-activation portType="Consume_Message_ptt" operation="Consume_Message"> <activation-spec className="oracle.tip.adapter.jms.inbound.JmsConsumeActivationSpec"> <property name="DurableSubscriber" value="MySubscriberID-1"/> <property name="PayloadType" value="TextMessage"/> <property name="UseMessageListener" value="false"/> <property name="DestinationName" value="jms/MyTestUDDTopic"/> </activation-spec> </endpoint-activation> </adapter-config> You can set the durable subscriber name either at composite's JmsAdapter wizard,or by directly editing the JmsAdapter's *.jca file within the Composite project. 2.The "atypical" configurations: For some systems, there may be restrictions that do not allow the afore mentioned "typical" configurations be applied. For examples, some deployments may be required to configure the JMS Topic to be Replicated Distributed Topic rather than Partition Distributed Topic. We would like to discuss those scenarios here: Configuration A: The JMS Topic is NOT PDT In this case, you need to define the message selector 'NOT JMS_WL_DDForwarded' in the adapter's *.jca file, to filter out those "replicated" messages. Configuration B. The ClientIDPolicy=RESTRICTED In this case, you need separate factories for different composites. More accurately, you need separate factories for different *.jca file of JmsAdapter. References: Managing Durable Subscription WebLogic JMS Partitioned Distributed Topics and Shared Subscriptions JMS Troubleshooting: Configuring JMS Message Logging: Advanced Programming with Distributed Destinations Using the JMS Destination Availability Helper API

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• Replication Services in a BI environment

  - by jorg

  In this blog post I will explain the principles of SQL Server Replication Services without too much detail and I will take a look on the BI capabilities that Replication Services could offer in my opinion. SQL Server Replication Services provides tools to copy and distribute database objects from one database system to another and maintain consistency afterwards. These tools basically copy or synchronize data with little or no transformations, they do not offer capabilities to transform data or apply business rules, like ETL tools do. The only “transformations” Replication Services offers is to filter records or columns out of your data set. You can achieve this by selecting the desired columns of a table and/or by using WHERE statements like this: SELECT <published_columns> FROM [Table] WHERE [DateTime] >= getdate() - 60 There are three types of replication: Transactional Replication This type replicates data on a transactional level. The Log Reader Agent reads directly on the transaction log of the source database (Publisher) and clones the transactions to the Distribution Database (Distributor), this database acts as a queue for the destination database (Subscriber). Next, the Distribution Agent moves the cloned transactions that are stored in the Distribution Database to the Subscriber. The Distribution Agent can either run at scheduled intervals or continuously which offers near real-time replication of data! So for example when a user executes an UPDATE statement on one or multiple records in the publisher database, this transaction (not the data itself) is copied to the distribution database and is then also executed on the subscriber. When the Distribution Agent is set to run continuously this process runs all the time and transactions on the publisher are replicated in small batches (near real-time), when it runs on scheduled intervals it executes larger batches of transactions, but the idea is the same. Snapshot Replication This type of replication makes an initial copy of database objects that need to be replicated, this includes the schemas and the data itself. All types of replication must start with a snapshot of the database objects from the Publisher to initialize the Subscriber. Transactional replication need an initial snapshot of the replicated publisher tables/objects to run its cloned transactions on and maintain consistency. The Snapshot Agent copies the schemas of the tables that will be replicated to files that will be stored in the Snapshot Folder which is a normal folder on the file system. When all the schemas are ready, the data itself will be copied from the Publisher to the snapshot folder. The snapshot is generated as a set of bulk copy program (BCP) files. Next, the Distribution Agent moves the snapshot to the Subscriber, if necessary it applies schema changes first and copies the data itself afterwards. The application of schema changes to the Subscriber is a nice feature, when you change the schema of the Publisher with, for example, an ALTER TABLE statement, that change is propagated by default to the Subscriber(s). Merge Replication Merge replication is typically used in server-to-client environments, for example when subscribers need to receive data, make changes offline, and later synchronize changes with the Publisher and other Subscribers, like with mobile devices that need to synchronize one in a while. Because I don’t really see BI capabilities here, I will not explain this type of replication any further. Replication Services in a BI environment Transactional Replication can be very useful in BI environments. In my opinion you never want to see users to run custom (SSRS) reports or PowerPivot solutions directly on your production database, it can slow down the system and can cause deadlocks in the database which can cause errors. Transactional Replication can offer a read-only, near real-time database for reporting purposes with minimal overhead on the source system. Snapshot Replication can also be useful in BI environments, if you don’t need a near real-time copy of the database, you can choose to use this form of replication. Next to an alternative for Transactional Replication it can be used to stage data so it can be transformed and moved into the data warehousing environment afterwards. In many solutions I have seen developers create multiple SSIS packages that simply copies data from one or more source systems to a staging database that figures as source for the ETL process. The creation of these packages takes a lot of (boring) time, while Replication Services can do the same in minutes. It is possible to filter out columns and/or records and it can even apply schema changes automatically so I think it offers enough features here. I don’t know how the performance will be and if it really works as good for this purpose as I expect, but I want to try this out soon!

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• Big Data – Buzz Words: What is Hadoop – Day 6 of 21

  - by Pinal Dave

  In yesterday’s blog post we learned what is NoSQL. In this article we will take a quick look at one of the four most important buzz words which goes around Big Data – Hadoop. What is Hadoop? Apache Hadoop is an open-source, free and Java based software framework offers a powerful distributed platform to store and manage Big Data. It is licensed under an Apache V2 license. It runs applications on large clusters of commodity hardware and it processes thousands of terabytes of data on thousands of the nodes. Hadoop is inspired from Google’s MapReduce and Google File System (GFS) papers. The major advantage of Hadoop framework is that it provides reliability and high availability. What are the core components of Hadoop? There are two major components of the Hadoop framework and both fo them does two of the important task for it. Hadoop MapReduce is the method to split a larger data problem into smaller chunk and distribute it to many different commodity servers. Each server have their own set of resources and they have processed them locally. Once the commodity server has processed the data they send it back collectively to main server. This is effectively a process where we process large data effectively and efficiently. (We will understand this in tomorrow’s blog post). Hadoop Distributed File System (HDFS) is a virtual file system. There is a big difference between any other file system and Hadoop. When we move a file on HDFS, it is automatically split into many small pieces. These small chunks of the file are replicated and stored on other servers (usually 3) for the fault tolerance or high availability. (We will understand this in the day after tomorrow’s blog post). Besides above two core components Hadoop project also contains following modules as well. Hadoop Common: Common utilities for the other Hadoop modules Hadoop Yarn: A framework for job scheduling and cluster resource management There are a few other projects (like Pig, Hive) related to above Hadoop as well which we will gradually explore in later blog posts. A Multi-node Hadoop Cluster Architecture Now let us quickly see the architecture of the a multi-node Hadoop cluster. A small Hadoop cluster includes a single master node and multiple worker or slave node. As discussed earlier, the entire cluster contains two layers. One of the layer of MapReduce Layer and another is of HDFC Layer. Each of these layer have its own relevant component. The master node consists of a JobTracker, TaskTracker, NameNode and DataNode. A slave or worker node consists of a DataNode and TaskTracker. It is also possible that slave node or worker node is only data or compute node. The matter of the fact that is the key feature of the Hadoop. In this introductory blog post we will stop here while describing the architecture of Hadoop. In a future blog post of this 31 day series we will explore various components of Hadoop Architecture in Detail. Why Use Hadoop? There are many advantages of using Hadoop. Let me quickly list them over here: Robust and Scalable – We can add new nodes as needed as well modify them. Affordable and Cost Effective – We do not need any special hardware for running Hadoop. We can just use commodity server. Adaptive and Flexible – Hadoop is built keeping in mind that it will handle structured and unstructured data. Highly Available and Fault Tolerant – When a node fails, the Hadoop framework automatically fails over to another node. Why Hadoop is named as Hadoop? In year 2005 Hadoop was created by Doug Cutting and Mike Cafarella while working at Yahoo. Doug Cutting named Hadoop after his son’s toy elephant. Tomorrow In tomorrow’s blog post we will discuss Buzz Word – MapReduce. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• Can not print after upgrading from 12.x to 14.04

  - by user318889

  After upgrading from V12.04 to V14.04 I am not able to print. I am using an HP LaserJet 400 M451dn. The printer troubleshooter told me that there is no solution to the problem. This is the output of the advanced diagnositc output. (Due to limited space I cut the output!) Can anybody tell me what is going wrong. I am using the printer via USB ? Page 1 (Scheduler not running?): {'cups_connection_failure': False} Page 2 (Is local server publishing?): {'local_server_exporting_printers': False} Page 3 (Choose printer): {'cups_dest': , 'cups_instance': None, 'cups_queue': u'HP-LaserJet-400-color-M451dn', 'cups_queue_listed': True} Page 4 (Check printer sanity): {'cups_device_uri_scheme': u'hp', 'cups_printer_dict': {'device-uri': u'hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670', 'printer-info': u'Hewlett-Packard HP LaserJet 400 color M451dn', 'printer-is-shared': True, 'printer-location': u'Pinatubo', 'printer-make-and-model': u'HP LJ 300-400 color M351-M451 Postscript (recommended)', 'printer-state': 4, 'printer-state-message': u'', 'printer-state-reasons': [u'none'], 'printer-type': 8556636, 'printer-uri-supported': u'ipp://localhost:631/printers/HP-LaserJet-400-color-M451dn'}, 'cups_printer_remote': False, 'hplip_output': (['', '\x1b[01mHP Linux Imaging and Printing System (ver. 3.14.6)\x1b[0m', '\x1b[01mDevice Information Utility ver. 5.2\x1b[0m', '', 'Copyright (c) 2001-13 Hewlett-Packard Development Company, LP', 'This software comes with ABSOLUTELY NO WARRANTY.', 'This is free software, and you are welcome to distribute it', 'under certain conditions. See COPYING file for more details.', '', '', '\x1b[01mhp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670\x1b[0m', '', '\x1b[01mDevice Parameters (dynamic data):\x1b[0m', '\x1b[01m Parameter Value(s) \x1b[0m', ' ---------------------------- ----------------------------------------------------------', ' back-end hp ', " cups-printers ['HP-LaserJet-400-color-M451dn'] ", ' cups-uri hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670 ', ' dev-file ', ' device-state -1 ', ' device-uri hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670 ', ' deviceid ', ' error-state 101 ', ' host ', ' is-hp True ', ' panel 0 ', ' panel-line1 ', ' panel-line2 ', ' port 1 ', ' serial CNFF308670 ', ' status-code 5002 ', ' status-desc ', '\x1b[01m', 'Model Parameters (static data):\x1b[0m', '\x1b[01m Parameter Value(s) \x1b[0m', ' ---------------------------- ----------------------------------------------------------', ' align-type 0 ', ' clean-type 0 ', ' color-cal-type 0 ', ' copy-type 0 ', ' embedded-server-type 0 ', ' fax-type 0 ', ' fw-download False ', ' icon hp_color_laserjet_cp2025.png ', ' io-mfp-mode 1 ', ' io-mode 1 ', ' io-support 6 ', ' job-storage 0 ', ' linefeed-cal-type 0 ', ' model HP_LaserJet_400_color_M451dn ', ' model-ui HP LaserJet 400 Color m451dn ', ' model1 HP LaserJet 400 Color M451dn ', ' monitor-type 0 ', ' panel-check-type 0 ', ' pcard-type 0 ', ' plugin 0 ', ' plugin-reason 0 ', ' power-settings 0 ', ' ppd-name lj_300_400_color_m351_m451 ', ' pq-diag-type 0 ', ' r-type 0 ', ' r0-agent1-kind 4 ', ' r0-agent1-sku CE410A/CE410X ', ' r0-agent1-type 1 ', ' r0-agent2-kind 4 ', ' r0-agent2-sku CE411A ', ' r0-agent2-type 4 ', ' r0-agent3-kind 4 ', ' r0-agent3-sku CE413A ', ' r0-agent3-type 5 ', ' r0-agent4-kind 4 ', ' r0-agent4-sku CE412A ', ' r0-agent4-type 6 ', ' scan-src 0 ', ' scan-type 0 ', ' status-battery-check 0 ', ' status-dynamic-counters 0 ', ' status-type 3 ', ' support-released True ', ' support-subtype 2202411 ', ' support-type 2 ', ' support-ver 3.12.2 ', " tech-class ['Postscript'] ", " tech-subclass ['Normal'] ", ' tech-type 4 ', ' usb-pid 3882 ', ' usb-vid 1008 ', ' wifi-config 0 ', '\x1b[01m', 'Status History (most recent first):\x1b[0m', '\x1b[01m Date/Time Code Status Description User Job ID \x1b[0m', ' -------------------- ----- ---------------------------------------- -------- --------', ' 08/21/14 00:07:25 5012 Device communication error richard 0 ', ' 08/20/14 13:42:44 500 Started a print job richard 4214 ', '', '', 'Done.', ''], ['\x1b[35;01mwarning: No display found.\x1b[0m', '\x1b[31;01merror: hp-info -u/--gui requires Qt4 GUI support. Entering interactive mode.\x1b[0m', '\x1b[31;01merror: Unable to communicate with device (code=12): hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670\x1b[0m', '\x1b[31;01merror: Error opening device (Device not found).\x1b[0m', ''], 0), 'is_cups_class': False, 'local_cups_queue_attributes': {'charset-configured': u'utf-8', 'charset-supported': [u'us-ascii', u'utf-8'], 'color-supported': True, 'compression-supported': [u'none', u'gzip'], 'copies-default': 1, 'copies-supported': (1, 9999), 'cups-version': u'1.7.2', 'device-uri': u'hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670', 'document-format-default': u'application/octet-stream', 'document-format-supported': [u'application/octet-stream', u'application/pdf', u'application/postscript', u'application/vnd.adobe-reader-postscript', u'application/vnd.cups-command', u'application/vnd.cups-pdf', u'application/vnd.cups-pdf-banner', u'application/vnd.cups-postscript', u'application/vnd.cups-raw', u'application/vnd.samsung-ps', u'application/x-cshell', u'application/x-csource', u'application/x-perl', u'application/x-shell', u'image/gif', u'image/jpeg', u'image/png', u'image/tiff', u'image/urf', u'image/x-bitmap', u'image/x-photocd', u'image/x-portable-anymap', u'image/x-portable-bitmap', u'image/x-portable-graymap', u'image/x-portable-pixmap', u'image/x-sgi-rgb', u'image/x-sun-raster', u'image/x-xbitmap', u'image/x-xpixmap', u'image/x-xwindowdump', u'text/css', u'text/html', u'text/plain'], 'finishings-default': 3, 'finishings-supported': [3], 'generated-natural-language-supported': [u'en-us'], 'ipp-versions-supported': [u'1.0', u'1.1', u'2.0', u'2.1'], 'ippget-event-life': 15, 'job-creation-attributes-supported': [u'copies', u'finishings', u'ipp-attribute-fidelity', u'job-hold-until', u'job-name', u'job-priority', u'job-sheets', u'media', u'media-col', u'multiple-document-handling', u'number-up', u'output-bin', u'orientation-requested', u'page-ranges', u'print-color-mode', u'print-quality', u'printer-resolution', u'sides'], 'job-hold-until-default': u'no-hold', 'job-hold-until-supported': [u'no-hold', u'indefinite', u'day-time', u'evening', u'night', u'second-shift', u'third-shift', u'weekend'], 'job-ids-supported': True, 'job-k-limit': 0, 'job-k-octets-supported': (0, 470914416), 'job-page-limit': 0, 'job-priority-default': 50, 'job-priority-supported': [100], 'job-quota-period': 0, 'job-settable-attributes-supported': [u'copies', u'finishings', u'job-hold-until', u'job-name', u'job-priority', u'media', u'media-col', u'multiple-document-handling', u'number-up', u'output-bin', u'orientation-requested', u'page-ranges', u'print-color-mode', u'print-quality', u'printer-resolution', u'sides'], 'job-sheets-default': (u'none', u'none'), 'job-sheets-supported': [u'none', u'classified', u'confidential', u'form', u'secret', u'standard', u'topsecret', u'unclassified'], 'jpeg-k-octets-supported': (0, 470914416), 'jpeg-x-dimension-supported': (0, 65535), 'jpeg-y-dimension-supported': (1, 65535), 'marker-change-time': 0, 'media-bottom-margin-supported': [423], 'media-col-default': u'(unknown IPP value tag 0x34)', 'media-col-supported': [u'media-bottom-margin', u'media-left-margin', u'media-right-margin', u'media-size', u'media-source', u'media-top-margin', u'media-type'], 'media-default': u'iso_a4_210x297mm', 'media-left-margin-supported': [423], 'media-right-margin-supported': [423],

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• Windows Phone 8 Announcement

  - by Tim Murphy

  As if the Surface announcement on Monday wasn’t exciting enough, today Microsoft announce that Windows Phone 8 will be coming this fall.  That itself is great news, but the features coming were like confetti flying in all different directions.  Given this speed I couldn’t capture every feature they covered.  A summary of what I did capture is listed below starting with their eight main features. Common Core The first thing that they covered is that Windows Phone 8 will share a core OS with Windows 8.  It will also run natively on multiple cores.  They mentioned that they have run it on up to 64 cores to this point.  The phones as you might expect will at least start as dual core.  If you remember there were metrics saying that Windows Phone 7 performed operations faster on a single core than other platforms did with dual cores.  The metrics they showed here indicate that Windows Phone 8 runs faster on comparable dual core hardware than other platforms. New Screen Resolutions Screen resolution has never been an issue for me, but it has been a criticism of Windows Phone 7 in the media.  Windows Phone 8 will supports three screen resolutions: WVGA 800 x 480, WXGA 1280 x 768, and 720 1280x720.  Hopefully this makes pixel counters a little happier. MicroSD Support This was one of my pet peeves when I got my Samsung Focus. With Windows Phone 8 the operating system will support adding MicroSD cards after initial setup.  Of course this is dependent on the hardware company on implementing it, but I think we have seen that even feature phone manufacturers have not had a problem supporting this in the past. NFC NFC has been an anticipated feature for some time.  What Microsoft showed today included the fact that they didn’t just want it to be for the phone.  There is cross platform NFC functionality between Windows Phone 8 and Windows 8.  The demos , while possibly a bit fanciful, showed would could be achieved even in a retail environment.  We are getting closer and closer to a Minority Report world with these technologies. Wallet Windows Phone 8 isn’t the first platform to have a wallet concept.  What they have done to differentiate themselves is to make it sot that it is not dependent on a SIM type chip like other platforms.  They have also expanded the concept beyond just banks to other types of credits such as airline miles. Nokia Mapping People have been envious of the Lumia phones having the Nokia mapping software.  Now all Windows Phone 8 devices will use NavTeq data and will have the capability to run in an offline fashion.  This is a major step forward from the Bing “touch for the next turn” maps. IT Administration The lack of features for enterprise administration and deployment was a complaint even before the Windows Phone 7 was released.  With the Windows Phone 8 release such features as Bitlocker and Secure boot will be baked into the OS. We will also have the ability to privately sign and distribute applications. Changing Start Screen Joe Belfiore made a big deal about this aspect of the new release.  Users will have more color themes available to them and the live tiles will be highly customizable. You will have the ability to resize and organize the tiles in a more dynamic way.  This allows for less important tiles or ones with less information to be made smaller.  And There Is More So what other tidbits came out of the presentation?  Later this summer the API for WP8 will be available.  There will be developer events coming to a city near you.  Another announcement of interest to developers is the ability to write applications at a native code level.  This is a boon for game developers and those who need highly efficient applications. As a topper on the cake there was mention of in app payment. On the consumer side we also found out that all updates will be available over the air.  Along with this came the fact that Microsoft will support all devices with updates for at least 18 month and you will be able to subscribe for early updates.  Update coming for Windows Phone 7.5 customers to WP7.8.  The main enhancement will be the new live tile features.  The big bonus is that the update will bypass the carriers.  I would assume though that you will be brought up to date with all previous patches that your carrier may not have released. There is so much more, but that is enough for one post.  Needless to say, EXCITING! del.icio.us Tags: Windows Phone 8,WP8,Windows Phone 7,WP7,Announcements,Microsoft

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• My own personal use of Oracle Linux

  - by wcoekaer

  It always is easier to explain something with examples... Many people still don't seem to understand some of the convenient things around using Oracle Linux and since I personally (surprise!) use it at home, let me give you an idea. I have quite a few servers at home and I also have 2 hosted servers with a hosted provider. The servers at home I use mostly to play with random Linux related things, or with Oracle VM or just try out various new Oracle products to learn more. I like the technology, it's like a hobby really. To be able to have a good installation experience and use an officially certified Linux distribution and not waste time trying to find the right libraries, I, of course, use Oracle Linux. Now, at least I can get a copy of Oracle Linux for free (even if I was not working for Oracle) and I can/could use that on as many servers at home (or at my company if I worked elsewhere) for testing, development and production. I just go to http://edelivery.oracle.com/linux and download the version(s) I want and off I go. Now, I also have the right (and not because I am an employee) to take those images and put them on my own server and give them to someone else, I in fact, just recently set up my own mirror on my own hosted server. I don't have to remove oracle-logos, I don't have to rebuild the ISO images, I don't have to recompile anything, I can just put the whole binary distribution on my own server without contract. Perfectly free to do so. Of course the source code of all of this is there, I have a copy of the UEK code at home, just cloned from https://oss.oracle.com/git/?p=linux-2.6-unbreakable.git. And as you can see, the entire changelog, checkins, merges from Linus's tree, complete overview of everything that got changed from kernel to kernel, from patch to patch, errata to errata. No obfuscating, no tar balls and spending time with diff, or go read bug reports to find out what changed (seems silly to me). Some of my servers are on the external network and I need to be current with security errata, but guess what, no problem, my servers are hooked up to http://public-yum.oracle.com which is open, free, and completely up to date, in a consistent, reliable way with any errata, security or bugfix. So I have nothing to worry about. Also, not because I am an employee. Anyone can. And, with this, I also can, and have, set up my own mirror site that hosts these RPMs. both binary and source rpms. Because I am free to get them and distribute them. I am quite capable of supporting my servers on my own, so I don't need to rely on the support organization so I don't need to have a support subscription :-). So I don't need to pay. Neither would you, at least not with Oracle Linux. Another cool thing. The hosted servers came (unfortunately) with Centos installed. While Centos works just fine as is, I tend to prefer to be current with my security errata(reliably) and I prefer to just maintain one yum repository instead of 2, I converted them over to Oracle Linux as well (in place) so they happily receive and use the exact same RPMs. Since Oracle Linux is exactly the same from a user/application point of view as RHEL, including files like /etc/redhat-release and no changes from .el. to .centos. I know I have nothing to worry about installing one of the RHEL applications. So, OL everywhere makes my life a lot easier and why not... Next! Since I run Oracle VM and I have -tons- of VM's on my machines, in some cases on my big WOPR box I have 15-20 VMs running. Well, no problem, OL is free and I don't have to worry about counting the number of VMs, whether it's 1, or 4, or more than 10 ... like some other alternatives started doing... and finally :) I like to try out new stuff, not 3 year old stuff. So with UEK2 as part of OL6 (and 6.3 in particular) I can play with a 3.0.x based kernel and it just installs and runs perfectly clean with OL6, so quite current stuff in an environment that I know works, no need to toy around with an unsupported pre-alpha upstream distribution with libraries and versions that are not compatible with production software (I have nothing against ubuntu or fedora or opensuse... just not what I can rely on or use for what I need, and I don't need a desktop). pretty compelling. I say... and again, it doesn't matter that I work for Oracle, if I was working elsewhere, or not at all, all of the above would still apply. Student, teacher, developer, whatever. contrast this with $349 for 2 sockets and oneguest and selfsupport per year to even just get the software bits.

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• Landscape orientation for UITabBarController?

  - by gingersnap

  The UITabBarController does not allow landscape orientation. So I used a subclass of UITabBarContoller (called RotatingTabBarController). Its sole purpose it to allow rotation by returning YES to shouldAutorotateToInterfaceOrientation call. The problem is that when you rotate the iPhone in simulator it gives the following malloc error. malloc: *** error for object 0x3888000: pointer being freed was not allocated *** set a breakpoint in malloc_error_break to debug I am using 3.0 SDK with Xcode 3.2 on Snow Leopard. I set a breakpoint in malloc_error_break but I can not trace it back to my code. Is there something I can do to make this error go away? Here is the RotatingTabBarController class: #import <UIKit/UIKit.h> @interface RotatingTabBarController : UITabBarController { } @end @implementation RotatingTabBarController -(BOOL)shouldAutorotateToInterfaceOrientation:UIInterfaceOrientation)interfaceOrientation { return YES; } @end Update: I tried the same with a category. But it gives the same malloc error. // UITabBarController+Rotation.h @interface UITabBarController (rotation) - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation; @end // UITabBarController+Rotation.m #import "UITabBarController+Rotation.h" @implementation UITabBarController (rotation) - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { return YES; } @end Backtrace [Session started at 2009-09-05 12:13:19 -0400.] Untitled(992,0xa06d9500) malloc: *** error for object 0x2024000: pointer being freed was not allocated *** set a breakpoint in malloc_error_break to debug Untitled(992,0xa06d9500) malloc: *** error for object 0x2014000: pointer being freed was not allocated *** set a breakpoint in malloc_error_break to debug [Session started at 2009-09-05 12:13:27 -0400.] GNU gdb 6.3.50-20050815 (Apple version gdb-1344) (Fri Jul 3 01:19:56 UTC 2009) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "x86_64-apple-darwin".Attaching to process 992. sharedlibrary apply-load-rules all (gdb) bt #0 0x951908fa in mach_msg_trap () #1 0x95191067 in mach_msg () #2 0x30244d62 in CFRunLoopRunSpecific () #3 0x30244628 in CFRunLoopRunInMode () #4 0x32044c31 in GSEventRunModal () #5 0x32044cf6 in GSEventRun () #6 0x309021ee in UIApplicationMain () #7 0x00002608 in main (argc=1, argv=0xbfffef94) at /Users/vishwas/Desktop/Untitled/main.m:13 (gdb)

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• activeX component in axapta

  - by Nico

  hi folks, i'm struggling with an .net activeX i try to use in ms axapta 2009. using this component on my local machine where it was compiled, it's working quite fine. it can be added as activeX element on a form, the methods and events are listed in the axapta-activeX-explorer and i can interact with it without any problems. but trying to distribute the dll to other clients isn't working as intended. the registration of the dll via regasm /codebase /tlb works properly - getting the message, registration was successful. the component is also listed when selecting an activeX-element to add in ax, but neither functions nor properties are listed. and launching the form results in an errormessage - activeX component CLSID ... not found on system, not installed. the classID is indeed the one, defined in .net. strange things happen, having a look on the task-manager. the activeX-component itself is just a wrapper to interact with a com-application. when launching the ax-form with the not working and _not_installed_!! activeX-thing, the taskmanager shows a new process of the com-application, which is instanciated by the activeX :/ things i tried: using different versions of regasm, eg \Windows\Microsoft.NET\Framework\v2.0.50727 ; C:\Windows\Microsoft.NET\Framework64\v2.0.50727 using new GUIDs in .net, prior removing the old ones from the registry compiling, using different versions of the .net framework doing registration via regasm, regasm /codebase, regasm /codebase /tlb, using a visual-studio-setup running registration via command-line as administrator running setup as administrator running even ax as administrator on client-machine moving dll to a different folder followed by new registration ( windows/system32; ax/client/bin ) installing to GAC ( gacutil /i ) different project-options in visual studio ( COM-Visibility; register for COM-Interop; different targetPlatform ) hoped for the fact, that compiling in visual studio with register for COM-Interop option enabled does something more than just the regasm-registration, i used a registry-monitor-microsoft-tool for logging the registry-activity which happend during compilation. using these logs to create all registry-entries on the target-client in addition didn't work either. any hints or help would be so much appreciated! this thing is blocking me for days now :(

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• Is MVVM pointless?

  - by joebeazelman

  Is orthodox MVVM implementation pointless? I am creating a new application and I considered Windows Forms and WPF. I chose WPF because it's future-proof and offer lots of flexibility. There is less code and easier to make significant changes to your UI using XAML. Since the choice for WPF is obvious, I figured that I may as well go all the way by using MVVM as my application architecture since it offers blendability, separation concerns and unit testability. Theoretically, it seems beautiful like the holy grail of UI programming. This brief adventure; however, has turned into a real headache. As expected in practice, I’m finding that I’ve traded one problem for another. I tend to be an obsessive programmer in that I want to do things the right way so that I can get the right results and possibly become a better programmer. The MVVM pattern just flunked my test on productivity and has just turned into a big yucky hack! The clear case in point is adding support for a Modal dialog box. The correct way is to put up a dialog box and tie it to a view model. Getting this to work is difficult. In order to benefit from the MVVM pattern, you have to distribute code in several places throughout the layers of your application. You also have to use esoteric programming constructs like templates and lamba expressions. Stuff that makes you stare at the screen scratching your head. This makes maintenance and debugging a nightmare waiting to happen as I recently discovered. I had an about box working fine until I got an exception the second time I invoked it, saying that it couldn’t show the dialog box again once it is closed. I had to add an event handler for the close functionality to the dialog window, another one in the IDialogView implementation of it and finally another in the IDialogViewModel. I thought MVVM would save us from such extravagant hackery! There are several folks out there with competing solutions to this problem and they are all hacks and don’t provide a clean, easily reusable, elegant solution. Most of the MVVM toolkits gloss over dialogs and when they do address them, they are just alert boxes that don’t require custom interfaces or view models. I’m planning on giving up on the MVVM view pattern, at least its orthodox implementation of it. What do you think? Has it been worth the trouble for you if you had any? Am I just a incompetent programmer or does MVVM not what it's hyped up to be?

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• Socket server with multiple clients, sending messages to many clients without hurting liveliness

  - by Karl Johanson

  I have a small socket server, and I need to distribute various messages from client-to-client depending on different conditionals. However I think I have a small problem with livelyness in my current code, and is there anything wrong in my approach: public class CuClient extends Thread { Socket socket = null; ObjectOutputStream out; ObjectInputStream in; CuGroup group; public CuClient(Socket s, CuGroup g) { this.socket = s; this.group = g; out = new ObjectOutputStream(this.socket.getOutputStream()); out.flush(); in = new ObjectInputStream(this.socket.getInputStream()); } @Override public void run() { String cmd = ""; try { while (!cmd.equals("client shutdown")) { cmd = (String) in.readObject(); this.group.broadcastToGroup(this, cmd); } out.close(); in.close(); socket.close(); } catch (Exception e) { System.out.println(this.getName()); e.printStackTrace(); } } public void sendToClient(String msg) { try { this.out.writeObject(msg); this.out.flush(); } catch (IOException ex) { } } And my CuGroup: public class CuGroup { private Vector<CuClient> clients = new Vector<CuClient>(); public void addClient(CuClient c) { this.clients.add(c); } void broadcastToGroup(CuClient clientName, String cmd) { Iterator it = this.clients.iterator(); while (it.hasNext()) { CuClient cu = (CuClient)it.next(); cu.sendToClient(cmd); } } } And my main-class: public class SmallServer { public static final Vector<CuClient> clients = new Vector<CuClient>(10); public static boolean serverRunning = true; private ServerSocket serverSocket; private CuGroup group = new CuGroup(); public void body() { try { this.serverSocket = new ServerSocket(1337, 20); System.out.println("Waiting for clients\n"); do { Socket s = this.serverSocket.accept(); CuClient t = new CuClient(s,group); System.out.println("SERVER: " + s.getInetAddress() + " is connected!\n"); t.start(); } while (this.serverRunning); } catch (IOException ex) { ex.printStackTrace(); } } public static void main(String[] args) { System.out.println("Server"); SmallServer server = new SmallServer(); server.body(); } } Consider the example with many more groups, maybe a Collection of groups. If they all synchronize on a single Object, I don't think my server will be very fast. I there a pattern or something that can help my liveliness?

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• Objective-C: properties not being saved or passed

  - by Gerald Yeo

  Hi, i'm a newbie to iphone development. I'm doing a navigation-based app, and I'm having trouble passing values to a new view. @interface RootViewController : UITableViewController { NSString *imgurl; NSMutableArray *galleryArray; } @property (nonatomic, retain) NSString *imgurl; @property (nonatomic, retain) NSMutableArray *galleryArray; - (void)showAll; @end #import "RootViewController.h" #import "ScrollView.h" #import "Model.h" #import "JSON/JSON.h" @implementation RootViewController @synthesize galleryArray, imgurl; - (void)viewDidLoad { UIBarButtonItem *showButton = [[[UIBarButtonItem alloc] initWithTitle:NSLocalizedString(@"Show All", @"") style:UIBarButtonItemStyleBordered target:self action:@selector(showAll)] autorelease]; self.navigationItem.rightBarButtonItem = showButton; NSString *jsonString = [[Model sharedInstance] jsonFromURLString:@"http://www.ddbstaging.com/gerald/gallery.php"]; NSDictionary *resultDictionary = [jsonString JSONValue]; if (resultDictionary == nil) { UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Webservice Down" message:@"The webservice you are accessing is currently down. Please try again later." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil]; [alert show]; [alert release]; } else { galleryArray = [[NSMutableArray alloc] init]; galleryArray = [resultDictionary valueForKey:@"gallery"]; imgurl = (NSString *)[galleryArray objectAtIndex:0]; NSLog(@" -> %@", galleryArray); NSLog(imgurl); } } - (void)showAll { NSLog(@" -> %@", galleryArray); NSLog(imgurl); ScrollView *controller = [[ScrollView alloc] initWithJSON:galleryArray]; [self.navigationController pushViewController:controller animated:YES]; } The RootViewController startup and the json data loads up fine. I can see it from the first console trace. However, once I click on the Show All button, the app crashes. It doesn't even trace the galleryArray and imgurl properyly. Maybe additional pairs of eyes can spot my mistakes. Any help is greatly appreciated! [Session started at 2010-05-08 16:16:07 +0800.] 2010-05-08 16:16:07.242 Photos[5892:20b] -> ( ) GNU gdb 6.3.50-20050815 (Apple version gdb-967) (Tue Jul 14 02:11:58 UTC 2009) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "i386-apple-darwin".sharedlibrary apply-load-rules all Attaching to process 5892. (gdb)

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• How to generate and encode (for use in GA), random, strict, binary rooted trees with N leaves?

  - by Peter Simon

  First, I am an engineer, not a computer scientist, so I apologize in advance for any misuse of nomenclature and general ignorance of CS background. Here is the motivational background for my question: I am contemplating writing a genetic algorithm optimizer to aid in designing a power divider network (also called a beam forming network, or BFN for short). The BFN is intended to distribute power to each of N radiating elements in an array of antennas. The fraction of the total input power to be delivered to each radiating element has been specified. Topologically speaking, a BFN is a strictly binary, rooted tree. Each of the (N-1) interior nodes of the tree represents the input port of an unequal, binary power splitter. The N leaves of the tree are the power divider outputs. Given a particular power divider topology, one is still free to map the power divider outputs to the array inputs in an arbitrary order. There are N! such permutations of the outputs. There are several considerations in choosing the desired ordering: 1) The power ratio for each binary coupler should be within a specified range of values. 2) The ordering should be chosen to simplify the mechanical routing of the transmission lines connecting the power divider. The number of ouputs N of the BFN may range from, say, 6 to 22. I have already written a genetic algorithm optimizer that, given a particular BFN topology and desired array input power distribution, will search through the N! permutations of the BFN outputs to generate a design with compliant power ratios and good mechanical routing. I would now like to generalize my program to automatically generate and search through the space of possible BFN topologies. As I understand it, for N outputs (leaves of the binary tree), there are $C_{N-1}$ different topologies that can be constructed, where $C_N$ is the Catalan number. I would like to know how to encode an arbitrary tree having N leaves in a way that is consistent with a chromosomal description for use in a genetic algorithm. Also associated with this is the need to generate random instances for filling the initial population, and to implement crossover and mutations operators for this type of chromosome. Any suggestions will be welcome. Please minimize the amount of CS lingo in your reply, since I am not likely to be acquainted with it. Thanks in advance, Peter

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• iPhone Image Resources, ICO vs PNG, app bundle filesize

  - by Jasarien

  My application has a collection of around 1940 icons that are used throughout. They're currently in ICO and new images provided to me come in ICO format too. I have noticed that they contain a 16x16 and 32x32 representation of each icon in one file. Each file is roughly 4KB in filesize (as reported by finder, but ls reports that they vary from being ~1000 bytes to 5000 bytes) A very small number of these icons only contain the 32x32 representation, and as a result are only around 700 bytes in size. Currently I am bundling these icons with my application and they are inflating the size of the app a bit more than I would like. Altogether, the images total just about 25.5MB. Xcode must do some kind of compression because the resulting app bundle is about 12.4MB. Compressing this further into a ZIP (as it would be when submitted to the App Store), results in a final file of 5.8MB. I'm aware that the maximum limit for over the air App Store downloads has been raised to 20MB since the introduction of the iPad (I'm not sure if that extends to iPhone apps as well as iPad apps though, if not the limit would be 10MB). My worry is that new icons are going to be added (sometimes up to 10 icons per week), and will continue to inflate the app bundle over time. What is the best way to distribute these icons with my app? Things I've tried and not had much success with: Converting the icons from ICO to PNG: I tried this in the hopes that the pngcrush utility would help out with the filesize. But it appears that it doesn't make much of a difference between a normal PNG and a crushed png (I believe it just optimises the image for display on the iPhone's GPU rather than compress it's size). Also in going from ICO to PNG actually increased the size of the icon file... Zipping the images, and then uncompressing them on first run. While this did reduce the overall image sizes, I found that the effort needed to unzip them, copy them to the documents folder and ensure that duplication doesn't happen on upgrades was too much hassle to be worth the benefit. Also, on original and 3G iPhones unzipping and copying around 25MB of images takes too long and creates a bad experience... Things I've considered but not yet tried: Instead of distributing the icons within the app bundle, host them online, and download each icon on demand (it depends on the user's data as to which icons will actually be displayed and when). Issues with this is that bandwidth costs money, and image downloads will be bandwidth intensive. However, my app currently has a small userbase of around 5,500 users (of which I estimate around 1500 to be active based on Flurry stats), and I have a huge unused bandwidth allowance with my current hosting package. So I'm open to thoughts on how to solve this tricky issue.

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• Windows Question: RunOnce/Second Boot Issues [closed]

  - by Greg

  Moved to Super User: Windows Question: RunOnce/Second Boot Issues I am attempting to create a Windows XP SP3 image that will run my application on Second Boot. Here is the intended workflow. 1) Run Image Prep Utility (I wrote) on windows to add my runonce entries and clean a few things up. 2) Reboot to ghost, make image file. 3) Package into my ISO and distribute. 4) System will be imaged by user. 5) On first boot, I have about 5 things that run, one of which includes a driver updater (I wrote) for my own specific devices. 6) One of the entries inside of HKCU/../runonce is a reg file, which adds another key to HKLM/../runonce. This is how second boot is acquired. 7) As a result of the driver updater, user is prompted to reboot. 8) My application is then launched from HKLM/../runonce on second boot. This workflow works perfectly, except for a select few legacy systems that contain devices that cause the add hardware wizard to pop up. When the add hardware wizard pops up is when I begin to see problems. It's important to note, that if I manually inspect the registry after the add hardware wizard pops up, it appears as I would expect, with all the first boot scripts having run, and it's sitting in a state I would correctly expect it to be in for a second boot scenario. The problem comes when I click next on the add hardware wizard, it seems to re-run the single entry I've added, and re-executes the runonce scripts. (only one script now as it's already executed and cleared out the initial entries). This causes my application to open as if it were a second boot, only when next is clicked on the add hardware wizard. If I click cancel, and reboot, then it also works as expected. I don't care as much about other solutions, because I could design a system that doesn't fully rely on Microsoft's registry. I simply can't find any information as to WHY this is happening. I believe this is some type of Microsoft issue that's presenting itself as a result of an overstretched image that's expected to support too many legacy platforms, but any help that can be provided would be appreciated. Thanks,

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• iPhone Debugger Message -- Weird

  - by Bill Shiff

  Hello, I have an iPhone app that I've been working on and have recently upgraded my version of XCode. Since the upgrade, I can build and debug in the iPhone Simulator just fine, but when I try to debug on an attached device I get the following messages: From Xcode4: GNU gdb 6.3.50-20050815 (Apple version gdb-1510) (Fri Oct 22 04:12:10 UTC 2010) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "--host=i386-apple-darwin --target=arm-apple-darwin".tty /dev/ttys001 sharedlibrary apply-load-rules all warning: Unable to read symbols from "dyld" (prefix __dyld_) (not yet mapped into memory). warning: Unable to read symbols for (null)/Library/Frameworks/MessageUI.framework/MessageUI (file not found). warning: Unable to read symbols from "MessageUI" (not yet mapped into memory). warning: Unable to read symbols for (null)/Library/Frameworks/MapKit.framework/MapKit (file not found). warning: Unable to read symbols from "MapKit" (not yet mapped into memory). warning: Unable to read symbols from "Foundation" (not yet mapped into memory). warning: Unable to read symbols for (null)/Library/Frameworks/UIKit.framework/UIKit (file not found). warning: Unable to read symbols from "UIKit" (not yet mapped into memory). warning: Unable to read symbols for (null)/Library/Frameworks/CoreGraphics.framework/CoreGraphics (file not found). warning: Unable to read symbols from "CoreGraphics" (not yet mapped into memory). warning: Unable to read symbols from "CoreData" (not yet mapped into memory). warning: Unable to read symbols from "QuartzCore" (not yet mapped into memory). warning: Unable to read symbols from "libgcc_s.1.dylib" (not yet mapped into memory). warning: Unable to read symbols from "libSystem.B.dylib" (not yet mapped into memory). warning: Unable to read symbols from "libobjc.A.dylib" (not yet mapped into memory). warning: Unable to read symbols from "CoreFoundation" (not yet mapped into memory). target remote-mobile /tmp/.XcodeGDBRemote-3836-28 Switching to remote-macosx protocol mem 0x1000 0x3fffffff cache mem 0x40000000 0xffffffff none mem 0x00000000 0x0fff none [Switching to thread 11523] [Switching to thread 11523] gdb stack crawl at point of internal error: 0 gdb-arm-apple-darwin 0x0013216e internal_vproblem + 316

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• A NSMutableArray is destroying my life!

  - by camilo

  EDITED to show the relevant part of the code Hi. There's a strange problem with an NSMutableArray which I'm just not understanding... Explaining: I have a NSMutableArray, defined as a property (nonatomic, retain), synthesized, and initialized with 29 elements. realSectionNames = [[NSMutableArray alloc] initWithCapacity:29]; After the initialization, I can insert elements as I wish and everything seems to be working fine. While I'm running the application, however, if I insert a new element in the array, I can print the array in the function where I inserted the element, and everything seems ok. However, when I select a row in the table, and I need to read that array, my application crashes. In fact, it cannot even print the array anymore. Is there any "magical and logical trick" everybody should know when using a NSMutableArray that a beginner like myself can be missing? Thanks a lot. I declare my array as realSectionNames = [[NSMutableArray alloc] initWithCapacity:29]; I insert objects in my array with [realSectionNames addObject:[category categoryFirstLetter]]; although I know i can also insert it with [realSectionNames insertObject:[category categoryFirstLetter] atIndex:i]; where the "i" is the first non-occupied position. After the insertion, I reload the data of my tableView. Printing the array before or after reloading the data shows it has the desired information. After that, selecting a row at the table makes the application crash. This realSectionNames is used in several UITableViewDelegate functions, but for the case it doesn't matter. What truly matters is that printing the array in the beginning of the didSelectRowAtIndexPath function crashes everything (and of course, doesn't print anything). I'm pretty sure it's in that line, for printing anything he line before works (example): NSLog(@"Anything"); NSLog(@"%@", realSectionNames); gives the output: 2010-03-24 15:16:04.146 myApplicationExperience[3527:207] Anything [Session started at 2010-03-24 15:16:04 +0000.] GNU gdb 6.3.50-20050815 (Apple version gdb-967) (Tue Jul 14 02:11:58 UTC 2009) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "i386-apple-darwin".sharedlibrary apply-load-rules all Attaching to process 3527. Still not understanding what kind of stupidity I've done this time... maybe it's not too late to follow the career of brain surgeon?

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• Primary language - C++/Qt, C#, Java?

  - by Airjoe

  I'm looking for some input, but let me start with a bit of background (for tl;dr skip to end). I'm an IT major with a concentration in networking. While I'm not a CS major nor do I want to program as a vocation, I do consider myself a programmer and do pretty well with the concepts involved. I've been programming since about 6th grade, started out with a proprietary game creation language that made my transition into C++ at college pretty easy. I like to make programs for myself and friends, and have been paid to program for local businesses. A bit about that- I wrote some programs for a couple local businesses in my senior year in high school. I wrote management systems for local shops (inventory, phone/pos orders, timeclock, customer info, and more stuff I can't remember). It definitely turned out to be over my head, as I had never had any formal programming education. It was a great learning experience, but damn was it crappy code. Oh yeah, by the way, it was all vb6. So, I've used vb6 pretty extensively, I've used c++ in my classes (intro to programming up to algorithms), used Java a little bit in another class (had to write a ping client program, pretty easy) and used Java for some simple Project Euler problems to help learn syntax and such when writing the program for the class. I've also used C# a bit for my own simple personal projects (simple programs, one which would just generate an HTTP request on a list of websites and notify if one responded unexpectedly or not at all, and another which just held a list of things to do and periodically reminded me to do them), things I would've written in vb6 a year or two ago. I've just started using Qt C++ for some undergrad research I'm working on. Now I've had some formal education, I [think I] understand organization in programming a lot better (I didn't even use classes in my vb6 programs where I really should have), how it's important to structure code, split into functions where appropriate, document properly, efficiency both in memory and speed, dynamic and modular programming etc. I was looking for some input on which language to pick up as my "primary". As I'm not a "real programmer", it will be mostly hobby projects, but will include some 'real' projects I'm sure. From my perspective: QtC++ and Java are cross platform, which is cool. Java and C# run in a virtual machine, but I'm not sure if that's a big deal (something extra to distribute, possibly a bit slower? I think Qt would require additional distributables too, right?). I don't really know too much more than this, so I appreciate any help, thanks! TL;DR Am an avocational programmer looking for a language, want quick and straight forward development, liked vb6, will be working with database driven GUI apps- should I go with QtC++, Java, C#, or perhaps something else?

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• Delegates does not work properly

  - by Warrior

  I am new to iPhone development. I am converting the date to the desired format and set it to the delegate and get its value in the another view. The session restarts when I tried to get the value from delegate. If I set the original date and not the formatted date in the set delegate, then i able to get the value in the another view. If I also give any static string value, then also I am able to the static string value back. Only the formatted date which is string is set then the session restarts. If i print and check the value of the formatted date it prints the correct formatted date only.Please help me out.Here is my code for date conversion NSString *dateval=[[stories objectAtIndex: storyIndex] objectForKey:@"date"]; NSDateFormatter *inputFormatter = [[NSDateFormatter alloc] init]; [inputFormatter setDateFormat:@"EEE, MMM dd, yyyy"]; NSDate *inputDate = [inputFormatter dateFromString:dateval]; NSDateFormatter *outputFormatter = [[NSDateFormatter alloc] init]; [outputFormatter setDateFormat:@"MMMM dd"]; NSString *outputDate = [outputFormatter stringFromDate:inputDate]; AppDelegate *delegate=(AppDelegate *)[[UIApplication sharedApplication]delegate]; [delegate setCurrentDates:outputDate]; EDIT: This is displayed in console inside view did load [Session started at 2010-04-21 19:12:53 +0530.] GNU gdb 6.3.50-20050815 (Apple version gdb-967) (Tue Jul 14 02:11:58 UTC 2009) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "i386-apple-darwin".sharedlibrary apply-load-rules all Attaching to process 4216. (gdb) In another view - (void)viewDidLoad { NSLog(@"inside view did load"); AppDelegate *delegate=(AppDelegate *)[[UIApplication sharedApplication]delegate]; NSString *titleValue=[delegate getCurrentDates]; self.navigationItem.title =titleValue ; } The get does not work properly.It works fine if i give any static string or the "dateval". Thanks.

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• How does your team work together in a remote setup?

  - by Carl Rosenberger

  Hi, we are a distributed team working on the object database db4o. The way we work: We try to program in pairs only. We use Skype and VNC or SharedView to connect and work together. In our online Tuesday meeting every week (usually about 1 hour) we talk about the tasks done last week we create new pairs for the next week with a random generator so knowledge and friendship distribute evenly we set the priority for any new tasks or bugs that have come in each team picks the tasks it likes to do from the highest prioritized ones. From Tuesday to Wednesday we estimate tasks. We have a unit of work we call "Ideal Developer Session" (IDS), maybe 2 or 3 hours of working together as a pair. It's not perfectly well defined (because we know estimation always is inaccurate) but from our past shared experience we have a common sense of what an IDS is. If we can't estimate a task because it feels too long for a week we break it down into estimatable smaller tasks. During a short meeting on Wednesday we commit to a workload we feel is well doable in a week. We commit to complete. If a team runs out of committed tasks during the week, it can pick new ones from the prioritized queue we have in Jira. When we started working this way, some of us found that remote pair programming takes a lot of energy because you are so focussed. If you pair program for more than 5 or 6 hours per day, you get drained. On the other hand working like this has turned out to be very efficient. The knowledge about our codebase is evenly distributed and we have really learnt lots from eachother. I would be very interested to hear about the experiences from other teams working in a similar way. Things like: How often do you meet? Have you tried different sprint lengths (one week, two week, longer) ? Which tools do you use? Which issue tracker do you use? What do you do about time zone differences? How does it work for you to integrate new people into the team? How many hours do you usually work per week? How does your management interact with the way you are working? Do you get put on a waterfall with hard deadlines? What's your unit of work? What is your normal velocity? (units of work done per week) Programming work should be fun and for us it usually is great fun. I would be happy about any new ideas how to make it even more fun and/or more efficient.

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• How do I create a safe local development environment?

  - by docgnome

  I'm currently doing web development with another developer on a centralized development server. In the past this has worked alright, as we have two separate projects we are working on and rarely conflict. Now, however, we are adding a third (possible) developer into the mix. This is clearly going to create problems with other developers changes affecting my work and vice versa. To solve this problem, I'm thinking the best solution would be to create a virtual machine to distribute between the developers for local use. The problem I have is when it comes to the database. Given that we all develop on laptops, simply keeping a local copy of the live data is plain stupid. I've considered sanitizing the data, but I can't really figure out how to replace the real data, with data that would be representative of what people actually enter with out repeating the same information over and over again, e.g. everyone's address becomes 123 Testing Lane, Test Town, WA, 99999 or something. Is this really something to be concerned about? Are there tools to help with this sort of thing? I'm using MySQL. Ideally, if I sanitized the db it should be done from a script that I can run regularly. If I do this I'd also need a way to reduce the size of the db itself. (I figure I could select all the records created after x and whack them and all the records in corresponding tables out so that isn't really a big deal.) The second solution I've thought of is to encrypt the hard drive of the vm, but I'm unsure of how practical this is in terms of speed and also in the event of a lost/stolen laptop. If I do this, should the vm hard drive file itself be encrypted or should it be encrypted in the vm? (I'm assuming the latter as it would be portable and doesn't require the devs to have any sort of encryption capability on their OS of choice.) The third is to create a copy of the database for each developer on our development server that they are then responsible to keep the schema in sync with the canonical db by means of migration scripts or what have you. This solution seems to be the simplest but doesn't really scale as more developers are added. How do you deal with this problem?

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• Primary language - QtC++, C#, Java?

  - by Airjoe

  I'm looking for some input, but let me start with a bit of background (for tl;dr skip to end). I'm an IT major with a concentration in networking. While I'm not a CS major nor do I want to program as a vocation, I do consider myself a programmer and do pretty well with the concepts involved. I've been programming since about 6th grade, started out with a proprietary game creation language that made my transition into C++ at college pretty easy. I like to make programs for myself and friends, and have been paid to program for local businesses. A bit about that- I wrote some programs for a couple local businesses in my senior year in high school. I wrote management systems for local shops (inventory, phone/pos orders, timeclock, customer info, and more stuff I can't remember). It definitely turned out to be over my head, as I had never had any formal programming education. It was a great learning experience, but damn was it crappy code. Oh yeah, by the way, it was all vb6. So, I've used vb6 pretty extensively, I've used c++ in my classes (intro to programming up to algorithms), used Java a little bit in another class (had to write a ping client program, pretty easy) and used Java for some simple Project Euler problems to help learn syntax and such when writing the program for the class. I've also used C# a bit for my own simple personal projects (simple programs, one which would just generate an HTTP request on a list of websites and notify if one responded unexpectedly or not at all, and another which just held a list of things to do and periodically reminded me to do them), things I would've written in vb6 a year or two ago. I've just started using Qt C++ for some undergrad research I'm working on. Now I've had some formal education, I [think I] understand organization in programming a lot better (I didn't even use classes in my vb6 programs where I really should have), how it's important to structure code, split into functions where appropriate, document properly, efficiency both in memory and speed, dynamic and modular programming etc. I was looking for some input on which language to pick up as my "primary". As I'm not a "real programmer", it will be mostly hobby projects, but will include some 'real' projects I'm sure. From my perspective: QtC++ and Java are cross platform, which is cool. Java and C# run in a virtual machine, but I'm not sure if that's a big deal (something extra to distribute, possibly a bit slower? I think Qt would require additional distributables too, right?). I don't really know too much more than this, so I appreciate any help, thanks! TL;DR Am an avocational programmer looking for a language, want quick and straight forward development, liked vb6, will be working with database driven GUI apps- should I go with QtC++, Java, C#, or perhaps something else?

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