Search Results

Search found 9254 results on 371 pages for 'approach'.

Page 38/371 | < Previous Page | 34 35 36 37 38 39 40 41 42 43 44 45  | Next Page >

  • Setting useLegacyV2RuntimeActivationPolicy At Runtime

    - by Reed
    Version 4.0 of the .NET Framework included a new CLR which is almost entirely backwards compatible with the 2.0 version of the CLR.  However, by default, mixed-mode assemblies targeting .NET 3.5sp1 and earlier will fail to load in a .NET 4 application.  Fixing this requires setting useLegacyV2RuntimeActivationPolicy in your app.Config for the application.  While there are many good reasons for this decision, there are times when this is extremely frustrating, especially when writing a library.  As such, there are (rare) times when it would be beneficial to set this in code, at runtime, as well as verify that it’s running correctly prior to receiving a FileLoadException. Typically, loading a pre-.NET 4 mixed mode assembly is handled simply by changing your app.Config file, and including the relevant attribute in the startup element: <?xml version="1.0" encoding="utf-8" ?> <configuration> <startup useLegacyV2RuntimeActivationPolicy="true"> <supportedRuntime version="v4.0"/> </startup> </configuration> .csharpcode { background-color: #ffffff; font-family: consolas, "Courier New", courier, monospace; color: black; font-size: small } .csharpcode pre { background-color: #ffffff; font-family: consolas, "Courier New", courier, monospace; color: black; font-size: small } .csharpcode pre { margin: 0em } .csharpcode .rem { color: #008000 } .csharpcode .kwrd { color: #0000ff } .csharpcode .str { color: #006080 } .csharpcode .op { color: #0000c0 } .csharpcode .preproc { color: #cc6633 } .csharpcode .asp { background-color: #ffff00 } .csharpcode .html { color: #800000 } .csharpcode .attr { color: #ff0000 } .csharpcode .alt { background-color: #f4f4f4; margin: 0em; width: 100% } .csharpcode .lnum { color: #606060 } This causes your application to run correctly, and load the older, mixed-mode assembly without issues. For full details on what’s happening here and why, I recommend reading Mark Miller’s detailed explanation of this attribute and the reasoning behind it. Before I show any code, let me say: I strongly recommend using the official approach of using app.config to set this policy. That being said, there are (rare) times when, for one reason or another, changing the application configuration file is less than ideal. While this is the supported approach to handling this issue, the CLR Hosting API includes a means of setting this programmatically via the ICLRRuntimeInfo interface.  Normally, this is used if you’re hosting the CLR in a native application in order to set this, at runtime, prior to loading the assemblies.  However, the F# Samples include a nice trick showing how to load this API and bind this policy, at runtime.  This was required in order to host the Managed DirectX API, which is built against an older version of the CLR. This is fairly easy to port to C#.  Instead of a direct port, I also added a little addition – by trapping the COM exception received if unable to bind (which will occur if the 2.0 CLR is already bound), I also allow a runtime check of whether this property was setup properly: public static class RuntimePolicyHelper { public static bool LegacyV2RuntimeEnabledSuccessfully { get; private set; } static RuntimePolicyHelper() { ICLRRuntimeInfo clrRuntimeInfo = (ICLRRuntimeInfo)RuntimeEnvironment.GetRuntimeInterfaceAsObject( Guid.Empty, typeof(ICLRRuntimeInfo).GUID); try { clrRuntimeInfo.BindAsLegacyV2Runtime(); LegacyV2RuntimeEnabledSuccessfully = true; } catch (COMException) { // This occurs with an HRESULT meaning // "A different runtime was already bound to the legacy CLR version 2 activation policy." LegacyV2RuntimeEnabledSuccessfully = false; } } [ComImport] [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] [Guid("BD39D1D2-BA2F-486A-89B0-B4B0CB466891")] private interface ICLRRuntimeInfo { void xGetVersionString(); void xGetRuntimeDirectory(); void xIsLoaded(); void xIsLoadable(); void xLoadErrorString(); void xLoadLibrary(); void xGetProcAddress(); void xGetInterface(); void xSetDefaultStartupFlags(); void xGetDefaultStartupFlags(); [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)] void BindAsLegacyV2Runtime(); } } Using this, it’s possible to not only set this at runtime, but also verify, prior to loading your mixed mode assembly, whether this will succeed. In my case, this was quite useful – I am working on a library purely for internal use which uses a numerical package that is supplied with both a completely managed as well as a native solver.  The native solver uses a CLR 2 mixed-mode assembly, but is dramatically faster than the pure managed approach.  By checking RuntimePolicyHelper.LegacyV2RuntimeEnabledSuccessfully at runtime, I can decide whether to enable the native solver, and only do so if I successfully bound this policy. There are some tricks required here – To enable this sort of fallback behavior, you must make these checks in a type that doesn’t cause the mixed mode assembly to be loaded.  In my case, this forced me to encapsulate the library I was using entirely in a separate class, perform the check, then pass through the required calls to that class.  Otherwise, the library will load before the hosting process gets enabled, which in turn will fail. This code will also, of course, try to enable the runtime policy before the first time you use this class – which typically means just before the first time you check the boolean value.  As a result, checking this early on in the application is more likely to allow it to work. Finally, if you’re using a library, this has to be called prior to the 2.0 CLR loading.  This will cause it to fail if you try to use it to enable this policy in a plugin for most third party applications that don’t have their app.config setup properly, as they will likely have already loaded the 2.0 runtime. As an example, take a simple audio player.  The code below shows how this can be used to properly, at runtime, only use the “native” API if this will succeed, and fallback (or raise a nicer exception) if this will fail: public class AudioPlayer { private IAudioEngine audioEngine; public AudioPlayer() { if (RuntimePolicyHelper.LegacyV2RuntimeEnabledSuccessfully) { // This will load a CLR 2 mixed mode assembly this.audioEngine = new AudioEngineNative(); } else { this.audioEngine = new AudioEngineManaged(); } } public void Play(string filename) { this.audioEngine.Play(filename); } } Now – the warning: This approach works, but I would be very hesitant to use it in public facing production code, especially for anything other than initializing your own application.  While this should work in a library, using it has a very nasty side effect: you change the runtime policy of the executing application in a way that is very hidden and non-obvious.

    Read the article

  • Oracle OpenWorld 2013 – Wrap up by Sven Bernhardt

    - by JuergenKress
    OOW 2013 is over and we’re heading home, so it is time to lean back and reflecting about the impressions we have from the conference. First of all: OOW was great! It was a pleasure to be a part of it. As already mentioned in our last blog article: It was the biggest OOW ever. Parallel to the conference the America’s Cup took place in San Francisco and the Oracle Team America won. Amazing job by the team and again congratulations from our side Back to the conference. The main topics for us are: Oracle SOA / BPM Suite 12c Adaptive Case management (ACM) Big Data Fast Data Cloud Mobile Below we will go a little more into detail, what are the key takeaways regarding the mentioned points: Oracle SOA / BPM Suite 12c During the five days at OOW, first details of the upcoming major release of Oracle SOA Suite 12c and Oracle BPM Suite 12c have been introduced. Some new key features are: Managed File Transfer (MFT) for transferring big files from a source to a target location Enhanced REST support by introducing a new REST binding Introduction of a generic cloud adapter, which can be used to connect to different cloud providers, like Salesforce Enhanced analytics with BAM, which has been totally reengineered (BAM Console now also runs in Firefox!) Introduction of templates (OSB pipelines, component templates, BPEL activities templates) EM as a single monitoring console OSB design-time integration into JDeveloper (Really great!) Enterprise modeling capabilities in BPM Composer These are only a few points from what is coming with 12c. We are really looking forward for the new realese to come out, because this seems to be really great stuff. The suite becomes more and more integrated. From 10g to 11g it was an evolution in terms of developing SOA-based applications. With 12c, Oracle continues it’s way – very impressive. Adaptive Case Management Another fantastic topic was Adaptive Case Management (ACM). The Oracle PMs did a great job especially at the demo grounds in showing the upcoming Case Management UI (will be available in 11g with the next BPM Suite MLR Patch), the roadmap and the differences between traditional business process modeling. They have been very busy during the conference because a lot of partners and customers have been interested Big Data Big Data is one of the current hype themes. Because of huge data amounts from different internal or external sources, the handling of these data becomes more and more challenging. Companies have a need for analyzing the data to optimize their business. The challenge is here: the amount of data is growing daily! To store and analyze the data efficiently, it is necessary to have a scalable and flexible infrastructure. Here it is important that hardware and software are engineered to work together. Therefore several new features of the Oracle Database 12c, like the new in-memory option, have been presented by Larry Ellison himself. From a hardware side new server machines like Fujitsu M10 or new processors, such as Oracle’s new M6-32 have been announced. The performance improvements, when using one of these hardware components in connection with the improved software solutions were really impressive. For more details about this, please take look at our previous blog post. Regarding Big Data, Oracle also introduced their Big Data architecture, which consists of: Oracle Big Data Appliance that is preconfigured with Hadoop Oracle Exdata which stores a huge amount of data efficently, to achieve optimal query performance Oracle Exalytics as a fast and scalable Business analytics system Analysis of the stored data can be performed using SQL, by streaming the data directly from Hadoop to an Oracle Database 12c. Alternatively the analysis can be directly implemented in Hadoop using “R”. In addition Oracle BI Tools can be used to analyze the data. Fast Data Fast Data is a complementary approach to Big Data. A huge amount of mostly unstructured data comes in via different channels with a high frequency. The analysis of these data streams is also important for companies, because the incoming data has to be analyzed regarding business-relevant patterns in real-time. Therefore these patterns must be identified efficiently and performant. To do so, in-memory grid solutions in combination with Oracle Coherence and Oracle Event Processing demonstrated very impressive how efficient real-time data processing can be. One example for Fast Data solutions that was shown during the OOW was the analysis of twitter streams regarding customer satisfaction. The feeds with negative words like “bad” or “worse” have been filtered and after a defined treshold has been reached in a certain timeframe, a business event was triggered. Cloud Another key trend in the IT market is of course Cloud Computing and what it means for companies and their businesses. Oracle announced their Cloud strategy and vision – companies can focus on their real business while all of the applications are available via Cloud. This also includes Oracle Database or Oracle Weblogic, so that companies can also build, deploy and run their own applications within the cloud. Three different approaches have been introduced: Infrastructure as a Service (IaaS) Platform as a Service (PaaS) Software as a Service (SaaS) Using the IaaS approach only the infrastructure components will be managed in the Cloud. Customers will be very flexible regarding memory, storage or number of CPUs because those parameters can be adjusted elastically. The PaaS approach means that besides the infrastructure also the platforms (such as databases or application servers) necessary for running applications will be provided within the Cloud. Here customers can also decide, if installation and management of these infrastructure components should be done by Oracle. The SaaS approach describes the most complete one, hence all applications a company uses are managed in the Cloud. Oracle is planning to provide all of their applications, like ERP systems or HR applications, as Cloud services. In conclusion this seems to be a very forward-thinking strategy, which opens up new possibilities for customers to manage their infrastructure and applications in a flexible, scalable and future-oriented manner. As you can see, our OOW days have been very very interresting. We collected many helpful informations for our projects. The new innovations presented at the confernce are great and being part of this was even greater! We are looking forward to next years’ conference! Links: http://www.oracle.com/openworld/index.html http://thecattlecrew.wordpress.com/2013/09/23/first-impressions-from-oracle-open-world-2013 SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Mix Forum Technorati Tags: cattleCrew,Sven Bernhard,OOW2013,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

    Read the article

  • Benefits of Behavior Driven Development

    - by Aligned
    Originally posted on: http://geekswithblogs.net/Aligned/archive/2013/07/26/benefits-of-behavior-driven-development.aspxContinuing my previous article on BDD, I wanted to point out some benefits of BDD and since BDD is an extension of Test Driven Development (TDD), you get those as well. I’ll add another article on some possible downsides of this approach. There are many articles about the benefits of TDD and they apply to BDD. I’ve pointed out some here and copied some of the main points for each article, but there are many more including the book The Art of Unit Testing by Roy Osherove. http://geekswithblogs.net/leesblog/archive/2008/04/30/the-benefits-of-test-driven-development.aspx (Lee Brandt) Stability Accountability Design Ability Separated Concerns Progress Indicator http://tddftw.com/benefits-of-tdd/ Help maintainers understand the intention behind the code Bring validation and proper data handling concerns to the forefront. Writing the tests first is fun. Better APIs come from writing testable code. TDD will make you a better developer. http://www.slideshare.net/dhelper/benefit-from-unit-testing-in-the-real-world (from Typemock). Take a look at the slides, especially the extra time required for TDD (slide 10) and the next one of the bugs avoided using TDD (slide 11). Less bugs (slide 11) about testing and development (13) Increase confidence in code (14) Fearlessly change your code (14) Document Requirements (14) also see http://visualstudiomagazine.com/articles/2013/06/01/roc-rocks.aspx Discover usability issues early (14) All these points and articles are great and there are many more. The following are my additions to the benefits of BDD from using it in real projects for my company. July 2013 on MSDN - Behavior-Driven Design with SpecFlow Scott Allen did a very informative TDD and MVC module, but to me he is doing BDDCompile and Execute Requirements in Microsoft .NET ~ Video from TechEd 2012 Communication I was working through a complicated task that the decision tree kept growing. After writing out the Given, When, Then of the scenario, I was able tell QA what I had worked through for their initial test cases. They were able to add from there. It is also useful to use this language with other developers, managers, or clients to help make informed decisions on if it meets the requirements or if it can simplified to save time (money). Thinking through solutions, before starting to code This was the biggest benefit to me. I like to jump into coding to figure out the problem. Many times I don't understand my path well enough and have to do some parts over. A past supervisor told me several times during reviews that I need to get better at seeing "the forest for the trees". When I sit down and write out the behavior that I need to implement, I force myself to think things out further and catch scenarios before they get to QA. A co-worker that is new to BDD and we’ve been using it in our new project for the last 6 months, said “It really clarifies things”. It took him awhile to understand it all, but now he’s seeing the value of this approach (yes there are some downsides, but that is a different issue). Developers’ Confidence This is huge for me. With tests in place, my confidence grows that I won’t break code that I’m not directly changing. In the past, I’ve worked on projects with out tests and we would frequently find regression bugs (or worse the users would find them). That isn’t fun. We don’t catch all problems with the tests, but when QA catches one, I can write a test to make sure it doesn’t happen again. It’s also good for Releasing code, telling your manager that it’s good to go. As time goes on and the code gets older, how confident are you that checking in code won’t break something somewhere else? Merging code - pre release confidence If you’re merging code a lot, it’s nice to have the tests to help ensure you didn’t merge incorrectly. Interrupted work I had a task that I started and planned out, then was interrupted for a month because of different priorities. When I started it up again, and un-shelved my changes, I had the BDD specs and it helped me remember what I had figured out and what was left to do. It would have much more difficult without the specs and tests. Testing and verifying complicated scenarios Sometimes in the UI there are scenarios that get tricky, because there are a lot of steps involved (click here to open the dialog, enter the information, make sure it’s valid, when I click cancel it should do {x}, when I click ok it should close and do {y}, then do this, etc….). With BDD I can avoid some of the mouse clicking define the scenarios and have them re-run quickly, without using a mouse. UI testing is still needed, but this helps a bunch. The same can be true for tricky server logic. Documentation of Assumptions and Specifications The BDD spec tests (Jasmine or SpecFlow or other tool) also work as documentation and show what the original developer was trying to accomplish. It’s not a different Word document, so developers will keep this up to date, instead of letting it become obsolete. What happens if you leave the project (consulting, new job, etc) with no specs or at the least good comments in the code? Sometimes I think of a new scenario, so I add a failing spec and continue in the same stream of thought (don’t forget it because it was on a piece of paper or in a notepad). Then later I can come back and handle it and have it documented. Jasmine tests and JavaScript –> help deal with the non-typed system I like JavaScript, but I also dislike working with JavaScript. I miss C# telling me if a property doesn’t actually exist at build time. I like the idea of TypeScript and hope to use it more in the future. I also use KnockoutJs, which has observables that need to be called with ending (), since the observable is a function. It’s hard to remember when to use () or not and the Jasmine specs/tests help ensure the correct usage.   This should give you an idea of the benefits that I see in using the BDD approach. I’m sure there are more. It talks a lot of practice, investment and experimentation to figure out how to approach this and to get comfortable with it. I agree with Scott Allen in the video I linked above “Remember that TDD can take some practice. So if you're not doing test-driven design right now? You can start and practice and get better. And you'll reach a point where you'll never want to get back.”

    Read the article

  • Find the set of largest contiguous rectangles to cover multiple areas

    - by joelpt
    I'm working on a tool called Quickfort for the game Dwarf Fortress. Quickfort turns spreadsheets in csv/xls format into a series of commands for Dwarf Fortress to carry out in order to plot a "blueprint" within the game. I am currently trying to optimally solve an area-plotting problem for the 2.0 release of this tool. Consider the following "blueprint" which defines plotting commands for a 2-dimensional grid. Each cell in the grid should either be dug out ("d"), channeled ("c"), or left unplotted ("."). Any number of distinct plotting commands might be present in actual usage. . d . d c c d d d d c c . d d d . c d d d d d c . d . d d c To minimize the number of instructions that need to be sent to Dwarf Fortress, I would like to find the set of largest contiguous rectangles that can be formed to completely cover, or "plot", all of the plottable cells. To be valid, all of a given rectangle's cells must contain the same command. This is a faster approach than Quickfort 1.0 took: plotting every cell individually as a 1x1 rectangle. This video shows the performance difference between the two versions. For the above blueprint, the solution looks like this: . 9 . 0 3 2 8 1 1 1 3 2 . 1 1 1 . 2 7 1 1 1 4 2 . 6 . 5 4 2 Each same-numbered rectangle above denotes a contiguous rectangle. The largest rectangles take precedence over smaller rectangles that could also be formed in their areas. The order of the numbering/rectangles is unimportant. My current approach is iterative. In each iteration, I build a list of the largest rectangles that could be formed from each of the grid's plottable cells by extending in all 4 directions from the cell. After sorting the list largest first, I begin with the largest rectangle found, mark its underlying cells as "plotted", and record the rectangle in a list. Before plotting each rectangle, its underlying cells are checked to ensure they are not yet plotted (overlapping a previous plot). We then start again, finding the largest remaining rectangles that can be formed and plotting them until all cells have been plotted as part of some rectangle. I consider this approach slightly more optimized than a dumb brute-force search, but I am wasting a lot of cycles (re)calculating cells' largest rectangles and checking underlying cells' states. Currently, this rectangle-discovery routine takes the lion's share of the total runtime of the tool, especially for large blueprints. I have sacrificed some accuracy for the sake of speed by only considering rectangles from cells which appear to form a rectangle's corner (determined using some neighboring-cell heuristics which aren't always correct). As a result of this 'optimization', my current code doesn't actually generate the above solution correctly, but it's close enough. More broadly, I consider the goal of largest-rectangles-first to be a "good enough" approach for this application. However I observe that if the goal is instead to find the minimum set (fewest number) of rectangles to completely cover multiple areas, the solution would look like this instead: . 3 . 5 6 8 1 3 4 5 6 8 . 3 4 5 . 8 2 3 4 5 7 8 . 3 . 5 7 8 This second goal actually represents a more optimal solution to the problem, as fewer rectangles usually means fewer commands sent to Dwarf Fortress. However, this approach strikes me as closer to NP-Hard, based on my limited math knowledge. Watch the video if you'd like to better understand the overall strategy; I have not addressed other aspects of Quickfort's process, such as finding the shortest cursor-path that plots all rectangles. Possibly there is a solution to this problem that coherently combines these multiple strategies. Help of any form would be appreciated.

    Read the article

  • Using NServiceBus behind a custom web service

    - by Michael Stephenson
    In this post I'd like to talk about an architecture scenario we had recently and how we were able to utilise NServiceBus to help us address this problem. Scenario Cognos is a reporting system used by one of my clients. A while back we developed a web service façade to allow line of business applications to be able to access reports from Cognos to support their various functions. The service was intended to provide access to reports which were quick running reports or pre-generated reports which could be accessed real-time on demand. One of the key aims of the web service was to provide a simple generic interface to allow applications to get any report without needing to worry about the complex .net SDK for Cognos. The web service also supported multi-hop kerberos delegation so that report data could be accesses under the context of the end user. This service was working well for a period of time. The Problem The problem we encountered was that reports were now also required to be available to batch processes. The original design was optimised for low latency so users would enjoy a positive experience, however when the batch processes started to request 250+ concurrent reports over an extended period of time you can begin to imagine the sorts of problems that come into play. The key problems this new scenario caused are: Users may be affected and the latency of on demand reports was significantly slower The Cognos infrastructure was not scaled sufficiently to be able to cope with these long peaks of load From a cost perspective it just isn't feasible to scale the Cognos infrastructure to be able to handle the load when it is only for a couple of hour window each night. We really needed to introduce a second pattern for accessing this service which would support high through-put scenarios. We also had little control over the batch process in terms of being able to throttle its load. We could however make some changes to the way it accessed the reports. The Approach My idea was to introduce a throttling mechanism between the Web Service Façade and Cognos. This would allow the batch processes to push reports requests hard at the web service which we were confident the web service can handle. The web service would then queue these requests and process them behind the scenes and make a call back to the batch application to provide the report once it had been accessed. In terms of technology we had some limitations because we were not able to use WCF or IIS7 where the MSMQ-Activated WCF services could have helped, but we did have MSMQ as an option and I thought NServiceBus could do just the job to help us here. The flow of how this would work was as follows: The batch applications would send a request for a report to the web service The web service uses NServiceBus to send the message to a Queue The NServiceBus Generic Host is running as a windows service with a message handler which subscribes to these messages The message handler gets the message, accesses the report from Cognos The message handler calls back to the original batch application, this is decoupled because the calling application provides a call back url The report gets into the batch application and is processed as normal This approach looks something like the below diagram: The key points are an application wanting to take advantage of the batch driven reports needs to do the following: Implement our call back contract Make a call to the service providing a call back url Provide a correlation ID so it knows how to tie each response back to its request What does NServiceBus offer in this solution So this scenario is not the typical messaging service bus type of solution people implement with NServiceBus, but it did offer the following: Simplified interaction with MSMQ Offered the ability to configure the number of processes working through the queue so we could find a balance between load on Cognos versus the applications end to end processing time NServiceBus offers retries and a way to manage failed messages NServiceBus offers a high availability setup The simple thing is that NServiceBus gave us the platform to build the solution on. We just implemented a message handler which functionally processed a message and we could rely on NServiceBus to do all of the hard work around managing the queues and all of the lower level things that would have took ages to write to any kind of robust level. Conclusion With this approach we were able to deal with a fairly significant performance issue with out too much rework. Hopefully this write up gives people some insight into ideas on how to leverage the excellent NServiceBus framework to help solve integration and high through-put scenarios.

    Read the article

  • Having fun with Reflection

    - by Nick Harrison
    I was once asked in a technical interview what I could tell them about Reflection.   My response, while a little tongue in cheek was that "I can tell you it is one of my favorite topics to talk about" I did get a laugh out of that and it was a great ice breaker.    Reflection may not be the answer for everything, but it often can be, or maybe even should be.     I have posted in the past about my favorite CopyTo method.   It can come in several forms and is often very useful.   I explain it further and expand on the basic idea here  The basic idea is to allow reflection to loop through the properties of two objects and synchronize the ones that are in common.   I love this approach for data binding and passing data across the layers in an application. Recently I have been working on a project leveraging Data Transfer Objects to pass data through WCF calls.   We won't go into how the architecture got this way, but in essence there is a partial duplicate inheritance hierarchy where there is a related Domain Object for each Data Transfer Object.     The matching objects do not share a common ancestor or common interface but they will have the same properties in common.    By passing the problems with this approach, let's talk about how Reflection and our friendly CopyTo could make the most of this bad situation without having to change too much. One of the problems is keeping the two sets of objects in synch.   For this particular project, the DO has all of the functionality and the DTO is used to simply transfer data back and forth.    Both sets of object have parallel hierarchies with the same properties being defined at the corresponding levels.   So we end with BaseDO,  BaseDTO, GenericDO, GenericDTO, ProcessAreaDO,  ProcessAreaDTO, SpecializedProcessAreaDO, SpecializedProcessAreaDTO, TableDo, TableDto. and so on. Without using Reflection and a CopyTo function, tremendous care and effort must be made to keep the corresponding objects in synch.    New properties can be added at any level in the inheritance and must be kept in synch at all subsequent layers.    For this project we have come up with a clever approach of calling a base GetDo or UpdateDto making sure that the same method at each level of inheritance is called.    Each level is responsible for updating the properties at that level. This is a lot of work and not keeping it in synch can create all manner of problems some of which are very difficult to track down.    The other problem is the type of code that this methods tend to wind up with. You end up with code like this: Transferable dto = new Transferable(); base.GetDto(dto); dto.OfficeCode = GetDtoNullSafe(officeCode); dto.AccessIndicator = GetDtoNullSafe(accessIndicator); dto.CaseStatus = GetDtoNullSafe(caseStatus); dto.CaseStatusReason = GetDtoNullSafe(caseStatusReason); dto.LevelOfService = GetDtoNullSafe(levelOfService); dto.ReferralComments = referralComments; dto.Designation = GetDtoNullSafe(designation); dto.IsGoodCauseClaimed = GetDtoNullSafe(isGoodCauseClaimed); dto.GoodCauseClaimDate = goodCauseClaimDate;       One obvious problem is that this is tedious code.   It is error prone code.    Adding helper functions like GetDtoNullSafe help out immensely, but there is still an easier way. We can bypass the tedious code, by pass the complex inheritance tricks, and reduce all of this to a single method in the base class. TransferObject dto = new TransferObject(); CopyTo (this, dto); return dto; In the case of this one project, such a change eliminated the need for 20% of the total code base and a whole class of unit test cases that made sure that all of the properties were in synch. The impact of such a change also needs to include the on going time savings and the improvements in quality that can arise from them.    Developers who are not worried about keeping the properties in synch across mirrored object hierarchies are freed to worry about more important things like implementing business requirements.

    Read the article

  • Unit Testing DateTime – The Crazy Way

    - by João Angelo
    We all know that the process of unit testing code that depends on DateTime, particularly the current time provided through the static properties (Now, UtcNow and Today), it’s a PITA. If you go ask how to unit test DateTime.Now on stackoverflow I’ll bet that you’ll get two kind of answers: Encapsulate the current time in your own interface and use a standard mocking framework; Pull out the big guns like Typemock Isolator, JustMock or Microsoft Moles/Fakes and mock the static property directly. Now each alternative has is pros and cons and I would have to say that I glean more to the second approach because the first adds a layer of abstraction just for the sake of testability. However, the second approach depends on commercial tools that not every shop wants to buy or in the not so friendly Microsoft Moles. (Sidenote: Moles is now named Fakes and it will ship with VS 2012) This tends to leave people without an acceptable and simple solution so after reading another of these types of questions in SO I came up with yet another alternative, one based on the first alternative that I presented here but tries really hard to not get in your way with yet another layer of abstraction. So, without further dues, I present you, the Tardis. The Tardis is single section of conditionally compiled code that overrides the meaning of the DateTime expression inside a single class. You still get the normal coding experience of using DateTime all over the place, but in a DEBUG compilation your tests will be able to mock every static method or property of the DateTime class. An example follows, while the full Tardis code can be downloaded from GitHub: using System; using NSubstitute; using NUnit.Framework; using Tardis; public class Example { public Example() : this(string.Empty) { } public Example(string title) { #if DEBUG this.DateTime = DateTimeProvider.Default; this.Initialize(title); } internal IDateTimeProvider DateTime { get; set; } internal Example(string title, IDateTimeProvider provider) { this.DateTime = provider; #endif this.Initialize(title); } private void Initialize(string title) { this.Title = title; this.CreatedAt = DateTime.UtcNow; } private string title; public string Title { get { return this.title; } set { this.title = value; this.UpdatedAt = DateTime.UtcNow; } } public DateTime CreatedAt { get; private set; } public DateTime UpdatedAt { get; private set; } } public class TExample { public void T001() { // Arrange var tardis = Substitute.For<IDateTimeProvider>(); tardis.UtcNow.Returns(new DateTime(2000, 1, 1, 6, 6, 6)); // Act var sut = new Example("Title", tardis); // Assert Assert.That(sut.CreatedAt, Is.EqualTo(tardis.UtcNow)); } public void T002() { // Arrange var tardis = Substitute.For<IDateTimeProvider>(); var sut = new Example("Title", tardis); tardis.UtcNow.Returns(new DateTime(2000, 1, 1, 6, 6, 6)); // Act sut.Title = "Updated"; // Assert Assert.That(sut.UpdatedAt, Is.EqualTo(tardis.UtcNow)); } } This approach is also suitable for other similar classes with commonly used static methods or properties like the ConfigurationManager class.

    Read the article

  • Meet Thomas, the Most Innovational person in Oracle Direct EMEA of Q1

    - by Maria Sandu
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Thomas was voted, by his peers,  the most Innovational person in Oracle Direct EMEA of Q1, the first quarter of this fiscal! Thomas, a Business Development Consultant at Oracle Direct’s Applications Team, taught himself how to use and leverage the power of social engagement consistent with Oracle’s Social Media Policy.  From these learning's he provided both his and other applications teams in Dublin with huge amounts of training and has presented his findings to the teams on more than one occasion. It is important to recognise that this isn't just a great idea....it actually works! The results speak for themselves. Thomas is engaging with customers and prospects via their preferred channel of communication and creating a strong personal social brand. We congratulate Thomas for his efforts of raising Social Media to the next level within Business Development Group. He put a lot of work into Social Selling, as one of the first within the BDG and set the example for a new innovative approach on how to sell anno 2013. He deserves to be recognized for this. His contribution to social media has been a great inspiration for all Business Development Consultants or Business Relationship Consultants. He knows what he talks about and has great conversion rates out of his social media campaigns. And he doesn't mind sharing his knowledge with everybody. Great effort in searching for new ways of communication and social selling. Thomas has shown great initiative towards leveraging the social media and networks (twitter, linkedin) to find new business opportunities in a previously way. He has shown great out-of-the-box thinking while addressing new companies and prospects and has shared those experiences and ideas to help his colleagues use the same approach. This included a presentation, informational emails and a general helpful attitude from him. He also shared his success stories from his innovational approach.  Thomas is showing initiative with an innovative and fresh character, truly helping people to try something new  with a focus on selling across channels and working for the CRM team which is focused on selling social. We think the way Thomas positions social, by using social is innovative and inspirational. What better way to tell your clients do social, by engaging with them on a social platform? Going always the extra mile, we believe, that Thomas Brits, is an innovator from the day he walked into Oracle Direct. The way Thomas operates on the work floor by introducing new ideas to find the best opportunities as possible shows he runs the extra mile for coming up with new ideas around how to engage with customers more efficiently for instance via Social Media. Thomas also organises power hours/days for the team. He is the best! /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

    Read the article

  • Chrome Web Browser Messages: Some Observations

    - by ultan o'broin
    I'm always on the lookout for how different apps handle errors and what kind of messages are shown (I probably need to get out more), I use this 'research' to reflect on our own application error messages patterns and guidelines and how we might make things better for our users in future. Users are influenced by all sorts of things, but their everyday experiences of technology, and especially what they encounter on the internet, increasingly sets their expectations for the enterprise user experience too. I recently came across a couple of examples from Google's Chrome web browser that got me thinking. In the first case, we have a Chrome error about not being able to find a web page. I like how simple, straightforward messaging language is used along with an optional ability to explore things a bit further--for those users who want to. The 'more information' option shows the error encountered by the browser (or 'original' error) in technical terms, along with an error number. Contrasting the two messages about essentially the same problem reveals what's useful to users and what's not. Everyone can use the first message, but the technical version of the message has to be explicitly disclosed for any more advanced user to pursue further. More technical users might search for a resolution, using that Error 324 number, but I imagine most users who see the message will try again later or check their URL again. Seems reasonable that such an approach be adopted in the enterprise space too, right? Maybe. Generally, end users don't go searching for solutions based on those error numbers, and help desk folks generally prefer they don't do so. That's because of the more critical nature of enterprise data or the fact that end users may not have the necessary privileges to make any fixes anyway. What might be more useful here is a link to a trusted source of additional help provided by the help desk or reputable community instead. This takes me on to the second case, this time more closely related to the language used in messaging situations. Here, I first noticed by the using of the (s) approach to convey possibilities of there being one or more pages at the heart of the problem. This approach is a no-no in Oracle style terms (the plural would be used) and it can create translation issues (though it is not a show-stopper). I think Google could have gone with the plural too. However, of more interest is the use of the verb "kill", shown in the message text and as an action button label. For many writers, words like "kill" and "abort" are to be avoided as they can give offense. I am not so sure about that judgment, as really their use cannot be separated from the context. Certainly, for more technical users, they're fine and have been in use for years, so I see no reason to avoid these terms if the audience has accepted them. Most end users too, I think would find the idea of "kill" usable and may even use the term in every day speech. Others might disagree--Apple uses a concept of Force Quit, for example. Ultimately, the only way to really know how to proceed is to research these matter by asking users of differing roles and expertise to perform some tasks, encounter these messages and then make recommendations based on those findings for our designs. Something to do in 2011!

    Read the article

  • Organizational characteristics that impact the selection of Development Methodology concepts applied to a project

    Based on my experience, no one really follows a specific methodology exactly as it is formally designed. In fact, the key concepts of a few methodologies are usually combined to form a hybrid methodology for each project based on the current organizational makeup and the project need/requirements to be accomplished. Organizational characteristics that impact the selection of methodology concepts applied to a project. Prior subject knowledge pertaining to a project can be critical when deciding on what methodology or combination of methodologies to apply to a project. For example, if a project is very straight forward, and the development staff has experience in developing  that are similar, then the waterfall method could possibly be the best choice because little to no research is needed  in order to complete the project tasks and there is very little need for changes to occur.  On the other hand, if the development staff has limited subject knowledge or the requirements/specification of the project could possibly change as the project progresses then the use of spiral, iterative, incremental, agile, or any combination would be preferred. The previous methodologies used by an organization typically do not change much from project to project unless the needs of a project dictate differently. For example, if the waterfall method is the preferred development methodology then most projects will be developed by the waterfall method. Depending on the time allotted to a project each day can impact the selection of a development methodology. In one example, if the staff can only devote a few hours a day to a project then the incremental methodology might be ideal because modules can be added to the final project as they are developed. On the other hand, if daily time allocation is not an issue, then a multitude of methodologies could work well for a project. Project characteristics that impact the selection of methodology concepts applied to a project. The type of project being developed can often dictate the type of methodology used for the project. Based on my experience, projects that tend to have a lot of user interaction, follow a more iterative, incremental, or agile approach typically using a prototype that develops into a final project. These methodologies desire back and forth communication between users, clients, and developers to allow for requirements to change and functionality to be enhanced. Conversely, limited interaction applications or automated services can still sometimes get away with using the waterfall or transactional approach. The timeline of a project can also force an organization to prefer a particular methodology over the rest. For instance, if the project must be completed within 24 hours, then there is very little time for discussions back and forth between clients, users and the development team. In this scenario, the waterfall method would be perfect because the only interaction with the client occurs prior to a development project to outline the system requirements, and the development team can quickly move through the software development stages in order to complete the project within the deadline. If the team had more time, then the other methodologies could also be considered because there is more time for client and users to review the project and make changes as they see fit, and/or allow for more time to review the project in order to enhance the business performance and functionality. Sometimes the client and or user involvement can dictate the selection of methodologies applied to a project. One example of this is if a client is highly motivated to get a project completed and desires to play an active part in the development process then the agile development approach would work perfectly with this client because it allows for frequent interaction between clients, users and the development team. The inverse of this situation is a client that just wants to provide the project requirements and only wants to get involved when the project is to be delivered. In this case the waterfall method would work well because there is no room for changes and no back and forth between the users, clients or the development team.

    Read the article

  • Project structure: where to put business logic

    - by Mister Smith
    First of all, I'm not asking where does business logic belong. This has been asked before and most answers I've read agree in that it belongs in the model: Where to put business logic in MVC design? How much business logic should be allowed to exist in the controller layer? How accurate is "Business logic should be in a service, not in a model"? Why put the business logic in the model? What happens when I have multiple types of storage? However people disagree in the way this logic should be distributed across classes. There seem to exist three major currents of thought: Fat model with business logic inside entity classes. Anemic model and business logic in "Service" classes. It depends. I find all of them problematic. The first option is what most Fowlerites stick to. The problem with a fat model is that sometimes a business logic funtion is not only related to a class, and instead uses a bunch of other classes. If, for example, we are developing a web store, there should be a function that calcs an order's total. We could think of putting this function inside the Order class, but what actually happens is that the logic needs to use different classes, not only data contained in the Order class, but also in the User class, the Session class, and maybe the Tax class, Country class, or Giftcard, Payment, etc. Some of these classes could be composed inside the Order class, but some others not. Sorry if the example is not very good, but I hope you understand what I mean. Putting such a function inside the Order class would break the single responsibility principle, adding unnecesary dependences. The business logic would be scattered across entity classes, making it hard to find. The second option is the one I usually follow, but after many projects I'm still in doubt about how to name the class or classes holding the business logic. In my company we usually develop apps with offline capabilities. The user is able to perform entire transactions offline, so all validation and business rules should be implemented in the client, and then there's usually a background thread that syncs with the server. So we usually have the following classes/packages in every project: Data model (DTOs) Data Access Layer (Persistence) Web Services layer (Usually one class per WS, and one method per WS method). Now for the business logic, what is the standard approach? A single class holding all the logic? Multiple classes? (if so, what criteria is used to distribute the logic across them?). And how should we name them? FooManager? FooService? (I know the last one is common, but in our case it is bad naming because the WS layer usually has classes named FooWebService). The third option is probably the right one, but it is also devoid of any useful info. To sum up: I don't like the first approach, but I accept that I might have been unable to fully understand the Zen of it. So if you advocate for fat models as the only and universal solution you are welcome to post links explaining how to do it the right way. I'd like to know what is the standard design and naming conventions for the second approach in OO languages. Class names and package structure, in particular. It would also be helpful too if you could include links to Open Source projects showing how it is done. Thanks in advance.

    Read the article

  • Site Review: Facebook.com and Blockbuster.com - Navigation Schemes

    After cycling through a list of my favorite sites I decided to select Facebook.com and Blockbuster.com for this  post because I found their navigation schemes very intuitive. Facebook in my opinion took a very simplistic and minimalistic approach when they designed their site and its navigation. For example, when you login to your account you will find on the upper left hand side a generic section of the site common areas to all users like news, messages, events, photos and friends. Below this in a separate navigation menu is a list of applications that a user has elected to access through bookmarks. Finally in the upper right hand corner of the site contains links to administer the user’s account like account settings, public profile, and a link back to the users’ home page. Blockbuster on the other had tried to make site navigation a little more slick by using a menu-submenu approach to navigation where user can click on things like Rent, Buy, On Demand, Games, Stores, and Gifts and a submenu of corresponding items appears below the original menu item. In addition they also took this approach and added categorized lists of movies that they offer on the homepage so that users can click on an item like “DVD Spotlight” and a list of movies represented as actual DVD box cases appear on the user’s screen so they can scroll through the list by using left and right arrows on either side of the images displayed. Both Facebook and Blockbuster have more than one navigation groupings because their respected sites are so large and offer an absorbent amount of features. Because of this reason they have to group the main functionality of information in to logical groups based on their actions they perform and the access to specific information. For example it would not make sense for Facebook to include a particular game you like to play within your account with a section pertaining to account administration. The game link would be completely out of place and really confuse the users experience because the groupings where not logically grouped. In addition I think that Facebook users would benefit if Facebook allowed its users to specify what they want on the general navigation from within their site or at least create a section to show frequently accessed pages or favorite sections. Finally regarding additional navigation, I think blockbuster users really benefit from the submenu system of categorizing data, and if fact Blockbuster even allows them to refine the information they are looking for through the use of secondary submenu systems allowing users to really drill down in to what they are looking for to learn more on. I do not think that having more than one navigation bar on a web page is not confusing for the user. For example if you have a navigation bar at the top of your page and at the bottom will allow users to move around the website easier because they can utilize the navigation closest to where their cursor is on the page. In regards to designers forcing all the navigation in to one navigation bar, I think it would be hard for the user to fully understand what is going on based on the size and complexity of the site they are dealing with. For example Blockbuster has a ton of content that could not easily be put in to one navigation bar. From my experience with both Facebook and Blockbuster, they both do a good job with cross browser compatibility. I have had no issues with either site in IE, Firefox, Chrome, and Safari over the years. In addition, I do not believe that either Facebook or Blockbuster require any additional plug-in to utilize their navigation bars.

    Read the article

  • Best of OTN - Week of Oct 21st

    - by CassandraClark-OTN
    This week's Best of OTN, for you, the best devs, dba's, sysadmins and architects out there!  In these weekly posts the OTN team will highlight the top content from each community; Architect, Database, Systems and Java.  Since we'll be publishing this on Fridays, we'll also mix in a little fun! Architect Community Top Content- The Road Ahead for WebLogic 12c | Edwin BiemondOracle ACE Edwin Biemond shares his thoughts on announced new features in Oracle WebLogic 12.1.3 & 12.1.4 and compares those upcoming releases to Oracle WebLogic 12.1.2. A Roadmap for SOA Development and Delivery | Mark NelsonDo you know the way to S-O-A? Mark Nelson does. His latest blog post, part of an ongoing series, will help to keep you from getting lost along the way. Updated ODI Statement of Direction | Robert SchweighardtHeads up Oracle Data Integrator fans! A new statement of product direction document is available, offering an overview of the strategic product plans for Oracle’s data integration products for bulk data movement and transformation, specifically Oracle Data Integrator (ODI) and Oracle Warehouse Builder (OWB). Bob Rhubart, Architect Community Manager Friday Funny - "Some people approach every problem with an open mouth." — Adlai E. Stevenson (October 23, 1835 – June 14, 1914) 23rd Vice President of the United States Database Community Top Content - Pre-Built Developer VMs (for Oracle VM VirtualBox)Heard all the chatter about Oracle VirtualBox? Over 1 million downloads per week and look: pre-built virtual appliances designed specifically for developers. Video: Big Data, or BIG DATA?Oracle Ace Director Ben Prusinski explains the differences.?? Webcast Series - Developing Applications in Oracle's Public CloudTime to get started on developing and deploying cloud applications by moving to the cloud. Good friend Gene Eun from Oracle's Cloud team posted this two-part Webcast series that has an overview and demonstration of the Oracle Database Cloud Service. Check out the demos on how to migrate your data to the cloud, extend your application with interactive reporting, and create and access RESTful Web services. Registration required, but so worth it! Laura Ramsey, Database Community Manager Friday Funny - Systems Community Top Content - Video: What Kind of Scalability is Better, Horizontal or Vertical?Rick Ramsey asks the question "Is Oracle's approach to large vertically scaled servers at odds with today's trend of combining lots and lots of small, low-cost servers systems with networking to build a cloud, or is it a better approach?" Michael Palmeter, Director of Solaris Product Management, and Renato Ribeiro, Director Product Management for SPARC Servers, discuss.Video: An Engineer Takes a Minute to Explain CloudBart Smaalders, long-time Oracle Solaris core engineer, takes a minute to explain cloud from a sysadmin point of view. ?Hands-On Lab: How to Deploy and Manage a Private IaaS Cloud Soup to nuts. This lab shows you how to set up and manage a private cloud with Oracle Enterprise Manager Cloud Control 12c in an Infrastructure as a service (IaaS) model. You will first configure the IaaS cloud as the cloud administrator and then deploy guest virtual machines (VMs) as a self-service user. Rick Ramsey, Systems Community Manager Friday Funny - Video: Drunk Airline Pilot - Dean Martin - Foster Brooks Java Community Top Content - Video: NightHacking Interview with James GoslingJames Gosling, the Father of Java, discusses robotics, Java and how to keep his autonomous WaveGliders in the ocean for weeks at a time. Live from Hawaii.  Video: Raspberry Pi Developer Challenge: Remote Controller A developer who knew nothing about Java Embedded or Raspberry Pi shows how he can now control a robot with his phone. The project was built during the Java Embedded Challenge for Raspberry Pi at JavaOne 2013.Java EE 7 Certification Survey - Participants NeededHelp us define how to server your training and certification needs for Java EE 7. Tori Wieldt, Java Community Manager Friday Funny - Programmers have a strong sensitivity to Yak's pheromone. Causes irresistible desire to shave said Yak. Thanks, @rickasaurus! To follow and take part in the conversation follow/like etc. at one or all of the resources below -  OTN TechBlog The Java Source Blog The OTN Garage Blog The OTN ArchBeat Blog @oracletechnet @java @OTN_Garage @OTNArchBeat @OracleDBDev OTN I Love Java OTN Garage OTN ArchBeat Oracle DB Dev OTN Java

    Read the article

  • Best depth sorting method for a Top Down 2D game using a 3D physics engine

    - by Alic44
    I've spent many days googling this and still have issues with my game engine I'd like to ask about, which I haven't seen addressed before. I think the problem is that my game is an unusual combination of a completely 2D graphical approach using XNA's SpriteBatch, and a completely 3D engine (the amazing BEPU physics engine) with rotation mostly disabled. In essence, my question is similar to this one (the part about "faux 3D"), but the difference is that in my game, the player as well as every other creature is represented by 3D objects, and they can all jump, pick up other objects, and throw them around. What this means is that sorting by one value, such as a Z position (how far north/south a character is on the screen) won't work, because as soon as a smaller creature jumps on top of a larger creature, or a box, and walks backwards, the moment its z value is less than that other creature, it will appear to be behind the object it is actually standing on. I actually originally solved this problem by splitting every object in the game into physics boxes which MUST have a Y height equal to their Z depth. I then based the depth sorting value on the object's y position (how high it is off the ground) PLUS its z position (how far north or south it is on the screen). The problem with this approach is that it requires all moving objects in the game to be split graphically into chunks which match up with a physical box which has its y dimension equal to its z dimension. Which is stupid. So, I got inspired last night to rewrite with a fresh approach. My new method is a little more complex, but I think a little more sane: every object which needs to be sorted by depth in the game exposes the interface IDepthDrawable and is added to a list owned by the DepthDrawer object. IDepthDrawable contains: public interface IDepthDrawable { Rectangle Bounds { get; } //possibly change this to a class if struct copying of the xna Rectangle type becomes an issue DepthDrawShape DepthShape { get; } void Draw(SpriteBatch spriteBatch); } The Bounds Rectangle of each IDepthDrawable object represents the 2D Axis-Aligned Bounding Box it will take up when drawn to the screen. Anything that doesn't intersect the screen will be culled at this stage and the remaining on-screen IDepthDrawables will be Bounds tested for intersections with each other. This is where I get a little less sure of what I'm doing. Each group of collisions will be added to a list or other collection, and each list will sort itself based on its DepthShape property, which will have access to the object-to-be-drawn's physics information. For starting out, lets assume everything in the game is an axis aligned 3D Box shape. Boxes are pretty easy to sort. Something like: if (depthShape1.Back > depthShape2.Front) //if depthShape1 is in front of depthShape2. //depthShape1 goes on top. else if (depthShape1.Bottom > depthShape2.Top) //if depthShape1 is above depthShape2. //depthShape1 goes on top. //if neither of these are true, depthShape2 must be in front or above. So, by sorting draw order by several different factors from the physics engine, I believe I can get a really correct draw order. My question is, is this a good way of going about this, or is there some tried and true, tested way which is completely different and has somehow completely eluded me on the internets? And, if this does seem like a good way to remake my draw order sorting, what's the right sorting algorithm for reordering the Bounds Rectangle collision lists, and how do you deal with a Bounds Rectangle colliding with two different object which don't collide with eachother. I know these are solved problems, but I've only been programming for a year so any specific input here will be greatly appreciated. Thanks for reading this far, ye who made it -- sorry it was so long!

    Read the article

  • My .NET Technology picks for 2011

    - by shiju
    My Technology predictions for 2011 Cloud computing and Mobile application development will be the hottest trends for 2011. I hope that Windows Azure will be very hot in year 2011 and lot of cloud computing adoption will be happen with Windows Azure on 2011. Web application scalability will be the big challenge for Architects in the next year and architecture approaches like CQRS will get some attention on next year. Architects will look on different options for web application scalability and adoption of NoSQL and Document databases will be more in the year 2011. The following are the my technology picks for .Net stack Windows Azure Windows Azure will be one of the hottest technologies of 2011. Adoption of Cloud and Windows Azure will get big attention on next year. The Windows Azure platform is a flexible cloud–computing platform that lets you focus on solving business problems and addressing customer needs. No need to invest upfront on expensive infrastructure. Pay only for what you use, scale up when you need capacity and pull it back when you don’t. We handle all the patches and maintenance — all in a secure environment with over 99.9% uptime. Silverlight 5 Silverlight is becoming a common technology for variety of development platforms. You can develop Silverlight applications for web, desktop and windows phone. The new Silverlight 5 beta will be available during the starting quarter of the next year with new capabilities and lot of new features. Silverlight 5 will be powerful development platform for both web-based business apps and rich media solutions. We can expect final version of Silverlight 5 on end of 2011. Windows Phone 7 Development Tools Mobile application development will be very hot in year 2011 and Windows Phone 7 will be one of the hottest technologies of next year. You can get introduction on Windows Phone 7 Development Tools from somasegar’s blog post and MSDN documentation available from here. EF Code First I am a big fan of Entity Framework’s Code First approach and hope that Code First approach will attract more people onto Entity Framework 4. EF Code First lets you focus on domain model which will enable Domain-Driven Development for applications. I hope that DDD fans will love the EF Code First approach. The Entity Framework 4 now supports three types of approaches and these will attract different types of developer audience. ASP.NET MVC 3 The ASP.NET MVC 3 will be the hottest technology of Microsoft web stack on the next year. ASP.NET developers will widely move to the ASP.NET MVC Framework from their WebForms development. The new Razor view engine is great and it will increase the adoption of ASP.NET MVC 3. Razor the will improve the productivity when working with ASP.NET MVC 3 Views. You can build great web applications using ASP.NET MVC 3 and jQuery with better maintainability, generation of clean HTML and even better performance. In my opinion, the best technology stack for web development is ASP.NET MVC 3 and Entity Framework 4 Code First as ORM. On the next year, you can expect more articles from my blog on ASP.NET MVC 3 and Entity Framework 4 Code First. RavenDB NoSQL and Document databases will get more attention on the coming year and RavenDB will be the most notable document database in the .NET stack. RavenDB is an Open Source (with a commercial option) document database for the .NET/Windows platform developed by Ayende Rahien. RavenDB is .NET focused document database which comes with a fully functional .NET client API and supports LINQ. I have written few articles on RavenDB and you can read it from here. Managed Extensibility Framework (MEF) Many people didn't realized the power of MEF. The MEF lets you create extensible applications and provides a great solution for the runtime extensibility problem. I hope that .NET developers will more adopt the MEF on the next year for their .NET applications. You can get an excellent introduction on MEF from Anoop Madhusudanan’s blog post MEF or Managed Extensibility Framework – Creating a Zoo and Animals

    Read the article

  • Investigating on xVelocity (VertiPaq) column size

    - by Marco Russo (SQLBI)
      In January I published an article about how to optimize high cardinality columns in VertiPaq. In the meantime, VertiPaq has been rebranded to xVelocity: the official name is now “xVelocity in-memory analytics engine (VertiPaq)” but using xVelocity and VertiPaq when we talk about Analysis Services has the same meaning. In this post I’ll show how to investigate on columns size of an existing Tabular database so that you can find the most important columns to be optimized. A first approach can be looking in the DataDir of Analysis Services and look for the folder containing the database. Then, look for the biggest files in all subfolders and you will find the name of a file that contains the name of the most expensive column. However, this heuristic process is not very optimized. A better approach is using a DMV that provides the exact information. For example, by using the following query (open SSMS, open an MDX query on the database you are interested to and execute it) you will see all database objects sorted by used size in a descending way. SELECT * FROM $SYSTEM.DISCOVER_STORAGE_TABLE_COLUMN_SEGMENTS ORDER BY used_size DESC You can look at the first rows in order to understand what are the most expensive columns in your tabular model. The interesting data provided are: TABLE_ID: it is the name of the object – it can be also a dictionary or an index COLUMN_ID: it is the column name the object belongs to – you can also see ID_TO_POS and POS_TO_ID in case they refer to internal indexes RECORDS_COUNT: it is the number of rows in the column USED_SIZE: it is the used memory for the object By looking at the ration between USED_SIZE and RECORDS_COUNT you can understand what you can do in order to optimize your tabular model. Your options are: Remove the column. Yes, if it contains data you will never use in a query, simply remove the column from the tabular model Change granularity. If you are tracking time and you included milliseconds but seconds would be enough, round the data source column to the nearest second. If you have a floating point number but two decimals are good enough (i.e. the temperature), round the number to the nearest decimal is relevant to you. Split the column. Create two or more columns that have to be combined together in order to produce the original value. This technique is described in VertiPaq optimization article. Sort the table by that column. When you read the data source, you might consider sorting data by this column, so that the compression will be more efficient. However, this technique works better on columns that don’t have too many distinct values and you will probably move the problem to another column. Sorting data starting from the lower density columns (those with a few number of distinct values) and going to higher density columns (those with high cardinality) is the technique that provides the best compression ratio. After the optimization you should be able to reduce the used size and improve the count/size ration you measured before. If you are interested in a longer discussion about internal storage in VertiPaq and you want understand why this approach can save you space (and time), you can attend my 24 Hours of PASS session “VertiPaq Under the Hood” on March 21 at 08:00 GMT.

    Read the article

  • Seperation of project responsibilities in new project

    - by dreza
    We have very recently started a new project (MVC 3.0) and some of our early discussion has been around how the work and development will be split amongst the team members to ensure we get the least amount of overlap of work and so help make it a bit easier for each developer to get on and do their work. The project is expected to take about 6 months - 1 year (although not all developers are likely to be on and might filter off towards the end), Our team is going to be small so this will help out a bit I believe. The team will essentially consist of: 3 x developers (1 a slightly more experienced and will be the lead) 1 x project manager / product owner / tester An external company responsbile for doing our design work General project/development decisions so far have included: Develop in an Agile way using SCRUM techniques (We are still very much learning this approach as a company) Use MVVM archectecture Use Ninject and DI where possible Attempt to use as TDD as much as possible to drive development. Keep our controllers as skinny as possible Keep our views as simple as possible During our discussions two approaches have been broached as too how to seperate the workload given our objectives outlined above. OPTION 1: A framework seperation where each person is responsible for conceptual areas with overlap and discussion primarily in the integration areas. The integration areas would the responsibily of both developers as required. View prototypes (**Graphic designer**) | - Mockups | Views (Razor and view helpers etc) & Javascript (**Developer 1**) | - View models (Integration point) | Controllers and Application logic (**Developer 2**) | - Models (Integration point) | Domain model and persistence (**Developer 3**) PROS: Integration points are quite clear and so developers can work without dependencies on others fairly easily Code practices such as naming conventions and style is more easily managed in regards to consistancy as primarily only one developer will be handling an area CONS: Completion of an entire feature becomes a bit grey as no single person is responsible for an entire feature (story?) A person might not have a full appreciation for all areas of the project and so code overlap might be lacking if suddenly that person left. OPTION 2: A more task orientated approach where each person is responsible for the completion of the entire task from view - controller - model. PROS: A person is responsible for one entire feature so it's "complete" state can be clearly defined Code overlap into different areas will occur so each individual has good coverage over the entire application CONS: Overlap of development will occur in all the modules and developers can develop/extend without a true understanding of what the original code owner was intending. This could potentially lead more easily to code bloat? Following a convention might be harder as developers are adding to all areas of the project If a developer sets up a way of doing things would it be harder to enforce the other developers to follow that convention or even build on it (or even discuss it?). Dunno.. Bugs could more easily be introduced into areas not thought about by the developer It's easier to possibly to carry a team member in so far as one member just hacks code together to complete a task whilst another takes time to build a foundation that could be used by others and so help make future tasks easier i.e. starts building a framework? QUESTION: As it might appear I'm more in favor of option 1, however I'm interested to see how others might have approached this or what is the standard or best or preferred way of undertaking a project. Or indeed any different approach to handling this?

    Read the article

  • Investigating on xVelocity (VertiPaq) column size

    - by Marco Russo (SQLBI)
      In January I published an article about how to optimize high cardinality columns in VertiPaq. In the meantime, VertiPaq has been rebranded to xVelocity: the official name is now “xVelocity in-memory analytics engine (VertiPaq)” but using xVelocity and VertiPaq when we talk about Analysis Services has the same meaning. In this post I’ll show how to investigate on columns size of an existing Tabular database so that you can find the most important columns to be optimized. A first approach can be looking in the DataDir of Analysis Services and look for the folder containing the database. Then, look for the biggest files in all subfolders and you will find the name of a file that contains the name of the most expensive column. However, this heuristic process is not very optimized. A better approach is using a DMV that provides the exact information. For example, by using the following query (open SSMS, open an MDX query on the database you are interested to and execute it) you will see all database objects sorted by used size in a descending way. SELECT * FROM $SYSTEM.DISCOVER_STORAGE_TABLE_COLUMN_SEGMENTS ORDER BY used_size DESC You can look at the first rows in order to understand what are the most expensive columns in your tabular model. The interesting data provided are: TABLE_ID: it is the name of the object – it can be also a dictionary or an index COLUMN_ID: it is the column name the object belongs to – you can also see ID_TO_POS and POS_TO_ID in case they refer to internal indexes RECORDS_COUNT: it is the number of rows in the column USED_SIZE: it is the used memory for the object By looking at the ration between USED_SIZE and RECORDS_COUNT you can understand what you can do in order to optimize your tabular model. Your options are: Remove the column. Yes, if it contains data you will never use in a query, simply remove the column from the tabular model Change granularity. If you are tracking time and you included milliseconds but seconds would be enough, round the data source column to the nearest second. If you have a floating point number but two decimals are good enough (i.e. the temperature), round the number to the nearest decimal is relevant to you. Split the column. Create two or more columns that have to be combined together in order to produce the original value. This technique is described in VertiPaq optimization article. Sort the table by that column. When you read the data source, you might consider sorting data by this column, so that the compression will be more efficient. However, this technique works better on columns that don’t have too many distinct values and you will probably move the problem to another column. Sorting data starting from the lower density columns (those with a few number of distinct values) and going to higher density columns (those with high cardinality) is the technique that provides the best compression ratio. After the optimization you should be able to reduce the used size and improve the count/size ration you measured before. If you are interested in a longer discussion about internal storage in VertiPaq and you want understand why this approach can save you space (and time), you can attend my 24 Hours of PASS session “VertiPaq Under the Hood” on March 21 at 08:00 GMT.

    Read the article

  • Much Ado About Nothing: Stub Objects

    - by user9154181
    The Solaris 11 link-editor (ld) contains support for a new type of object that we call a stub object. A stub object is a shared object, built entirely from mapfiles, that supplies the same linking interface as the real object, while containing no code or data. Stub objects cannot be executed — the runtime linker will kill any process that attempts to load one. However, you can link to a stub object as a dependency, allowing the stub to act as a proxy for the real version of the object. You may well wonder if there is a point to producing an object that contains nothing but linking interface. As it turns out, stub objects are very useful for building large bodies of code such as Solaris. In the last year, we've had considerable success in applying them to one of our oldest and thorniest build problems. In this discussion, I will describe how we came to invent these objects, and how we apply them to building Solaris. This posting explains where the idea for stub objects came from, and details our long and twisty journey from hallway idea to standard link-editor feature. I expect that these details are mainly of interest to those who work on Solaris and its makefiles, those who have done so in the past, and those who work with other similar bodies of code. A subsequent posting will omit the history and background details, and instead discuss how to build and use stub objects. If you are mainly interested in what stub objects are, and don't care about the underlying software war stories, I encourage you to skip ahead. The Long Road To Stubs This all started for me with an email discussion in May of 2008, regarding a change request that was filed in 2002, entitled: 4631488 lib/Makefile is too patient: .WAITs should be reduced This CR encapsulates a number of cronic issues with Solaris builds: We build Solaris with a parallel make (dmake) that tries to build as much of the code base in parallel as possible. There is a lot of code to build, and we've long made use of parallelized builds to get the job done quicker. This is even more important in today's world of massively multicore hardware. Solaris contains a large number of executables and shared objects. Executables depend on shared objects, and shared objects can depend on each other. Before you can build an object, you need to ensure that the objects it needs have been built. This implies a need for serialization, which is in direct opposition to the desire to build everying in parallel. To accurately build objects in the right order requires an accurate set of make rules defining the things that depend on each other. This sounds simple, but the reality is quite complex. In practice, having programmers explicitly specify these dependencies is a losing strategy: It's really hard to get right. It's really easy to get it wrong and never know it because things build anyway. Even if you get it right, it won't stay that way, because dependencies between objects can change over time, and make cannot help you detect such drifing. You won't know that you got it wrong until the builds break. That can be a long time after the change that triggered the breakage happened, making it hard to connect the cause and the effect. Usually this happens just before a release, when the pressure is on, its hard to think calmly, and there is no time for deep fixes. As a poor compromise, the libraries in core Solaris were built using a set of grossly incomplete hand written rules, supplemented with a number of dmake .WAIT directives used to group the libraries into sets of non-interacting groups that can be built in parallel because we think they don't depend on each other. From time to time, someone will suggest that we could analyze the built objects themselves to determine their dependencies and then generate make rules based on those relationships. This is possible, but but there are complications that limit the usefulness of that approach: To analyze an object, you have to build it first. This is a classic chicken and egg scenario. You could analyze the results of a previous build, but then you're not necessarily going to get accurate rules for the current code. It should be possible to build the code without having a built workspace available. The analysis will take time, and remember that we're constantly trying to make builds faster, not slower. By definition, such an approach will always be approximate, and therefore only incremantally more accurate than the hand written rules described above. The hand written rules are fast and cheap, while this idea is slow and complex, so we stayed with the hand written approach. Solaris was built that way, essentially forever, because these are genuinely difficult problems that had no easy answer. The makefiles were full of build races in which the right outcomes happened reliably for years until a new machine or a change in build server workload upset the accidental balance of things. After figuring out what had happened, you'd mutter "How did that ever work?", add another incomplete and soon to be inaccurate make dependency rule to the system, and move on. This was not a satisfying solution, as we tend to be perfectionists in the Solaris group, but we didn't have a better answer. It worked well enough, approximately. And so it went for years. We needed a different approach — a new idea to cut the Gordian Knot. In that discussion from May 2008, my fellow linker-alien Rod Evans had the initial spark that lead us to a game changing series of realizations: The link-editor is used to link objects together, but it only uses the ELF metadata in the object, consisting of symbol tables, ELF versioning sections, and similar data. Notably, it does not look at, or understand, the machine code that makes an object useful at runtime. If you had an object that only contained the ELF metadata for a dependency, but not the code or data, the link-editor would find it equally useful for linking, and would never know the difference. Call it a stub object. In the core Solaris OS, we require all objects to be built with a link-editor mapfile that describes all of its publically available functions and data. Could we build a stub object using the mapfile for the real object? It ought to be very fast to build stub objects, as there are no input objects to process. Unlike the real object, stub objects would not actually require any dependencies, and so, all of the stubs for the entire system could be built in parallel. When building the real objects, one could link against the stub objects instead of the real dependencies. This means that all the real objects can be built built in parallel too, without any serialization. We could replace a system that requires perfect makefile rules with a system that requires no ordering rules whatsoever. The results would be considerably more robust. We immediately realized that this idea had potential, but also that there were many details to sort out, lots of work to do, and that perhaps it wouldn't really pan out. As is often the case, it would be necessary to do the work and see how it turned out. Following that conversation, I set about trying to build a stub object. We determined that a faithful stub has to do the following: Present the same set of global symbols, with the same ELF versioning, as the real object. Functions are simple — it suffices to have a symbol of the right type, possibly, but not necessarily, referencing a null function in its text segment. Copy relocations make data more complicated to stub. The possibility of a copy relocation means that when you create a stub, the data symbols must have the actual size of the real data. Any error in this will go uncaught at link time, and will cause tragic failures at runtime that are very hard to diagnose. For reasons too obscure to go into here, involving tentative symbols, it is also important that the data reside in bss, or not, matching its placement in the real object. If the real object has more than one symbol pointing at the same data item, we call these aliased symbols. All data symbols in the stub object must exhibit the same aliasing as the real object. We imagined the stub library feature working as follows: A command line option to ld tells it to produce a stub rather than a real object. In this mode, only mapfiles are examined, and any object or shared libraries on the command line are are ignored. The extra information needed (function or data, size, and bss details) would be added to the mapfile. When building the real object instead of the stub, the extra information for building stubs would be validated against the resulting object to ensure that they match. In exploring these ideas, I immediately run headfirst into the reality of the original mapfile syntax, a subject that I would later write about as The Problem(s) With Solaris SVR4 Link-Editor Mapfiles. The idea of extending that poor language was a non-starter. Until a better mapfile syntax became available, which seemed unlikely in 2008, the solution could not involve extentions to the mapfile syntax. Instead, we cooked up the idea (hack) of augmenting mapfiles with stylized comments that would carry the necessary information. A typical definition might look like: # DATA(i386) __iob 0x3c0 # DATA(amd64,sparcv9) __iob 0xa00 # DATA(sparc) __iob 0x140 iob; A further problem then became clear: If we can't extend the mapfile syntax, then there's no good way to extend ld with an option to produce stub objects, and to validate them against the real objects. The idea of having ld read comments in a mapfile and parse them for content is an unacceptable hack. The entire point of comments is that they are strictly for the human reader, and explicitly ignored by the tool. Taking all of these speed bumps into account, I made a new plan: A perl script reads the mapfiles, generates some small C glue code to produce empty functions and data definitions, compiles and links the stub object from the generated glue code, and then deletes the generated glue code. Another perl script used after both objects have been built, to compare the real and stub objects, using data from elfdump, and validate that they present the same linking interface. By June 2008, I had written the above, and generated a stub object for libc. It was a useful prototype process to go through, and it allowed me to explore the ideas at a deep level. Ultimately though, the result was unsatisfactory as a basis for real product. There were so many issues: The use of stylized comments were fine for a prototype, but not close to professional enough for shipping product. The idea of having to document and support it was a large concern. The ideal solution for stub objects really does involve having the link-editor accept the same arguments used to build the real object, augmented with a single extra command line option. Any other solution, such as our prototype script, will require makefiles to be modified in deeper ways to support building stubs, and so, will raise barriers to converting existing code. A validation script that rederives what the linker knew when it built an object will always be at a disadvantage relative to the actual linker that did the work. A stub object should be identifyable as such. In the prototype, there was no tag or other metadata that would let you know that they weren't real objects. Being able to identify a stub object in this way means that the file command can tell you what it is, and that the runtime linker can refuse to try and run a program that loads one. At that point, we needed to apply this prototype to building Solaris. As you might imagine, the task of modifying all the makefiles in the core Solaris code base in order to do this is a massive task, and not something you'd enter into lightly. The quality of the prototype just wasn't good enough to justify that sort of time commitment, so I tabled the project, putting it on my list of long term things to think about, and moved on to other work. It would sit there for a couple of years. Semi-coincidentally, one of the projects I tacked after that was to create a new mapfile syntax for the Solaris link-editor. We had wanted to do something about the old mapfile syntax for many years. Others before me had done some paper designs, and a great deal of thought had already gone into the features it should, and should not have, but for various reasons things had never moved beyond the idea stage. When I joined Sun in late 2005, I got involved in reviewing those things and thinking about the problem. Now in 2008, fresh from relearning for the Nth time why the old mapfile syntax was a huge impediment to linker progress, it seemed like the right time to tackle the mapfile issue. Paving the way for proper stub object support was not the driving force behind that effort, but I certainly had them in mind as I moved forward. The new mapfile syntax, which we call version 2, integrated into Nevada build snv_135 in in February 2010: 6916788 ld version 2 mapfile syntax PSARC/2009/688 Human readable and extensible ld mapfile syntax In order to prove that the new mapfile syntax was adequate for general purpose use, I had also done an overhaul of the ON consolidation to convert all mapfiles to use the new syntax, and put checks in place that would ensure that no use of the old syntax would creep back in. That work went back into snv_144 in June 2010: 6916796 OSnet mapfiles should use version 2 link-editor syntax That was a big putback, modifying 517 files, adding 18 new files, and removing 110 old ones. I would have done this putback anyway, as the work was already done, and the benefits of human readable syntax are obvious. However, among the justifications listed in CR 6916796 was this We anticipate adding additional features to the new mapfile language that will be applicable to ON, and which will require all sharable object mapfiles to use the new syntax. I never explained what those additional features were, and no one asked. It was premature to say so, but this was a reference to stub objects. By that point, I had already put together a working prototype link-editor with the necessary support for stub objects. I was pleased to find that building stubs was indeed very fast. On my desktop system (Ultra 24), an amd64 stub for libc can can be built in a fraction of a second: % ptime ld -64 -z stub -o stubs/libc.so.1 -G -hlibc.so.1 \ -ztext -zdefs -Bdirect ... real 0.019708910 user 0.010101680 sys 0.008528431 In order to go from prototype to integrated link-editor feature, I knew that I would need to prove that stub objects were valuable. And to do that, I knew that I'd have to switch the Solaris ON consolidation to use stub objects and evaluate the outcome. And in order to do that experiment, ON would first need to be converted to version 2 mapfiles. Sub-mission accomplished. Normally when you design a new feature, you can devise reasonably small tests to show it works, and then deploy it incrementally, letting it prove its value as it goes. The entire point of stub objects however was to demonstrate that they could be successfully applied to an extremely large and complex code base, and specifically to solve the Solaris build issues detailed above. There was no way to finesse the matter — in order to move ahead, I would have to successfully use stub objects to build the entire ON consolidation and demonstrate their value. In software, the need to boil the ocean can often be a warning sign that things are trending in the wrong direction. Conversely, sometimes progress demands that you build something large and new all at once. A big win, or a big loss — sometimes all you can do is try it and see what happens. And so, I spent some time staring at ON makefiles trying to get a handle on how things work, and how they'd have to change. It's a big and messy world, full of complex interactions, unspecified dependencies, special cases, and knowledge of arcane makefile features... ...and so, I backed away, put it down for a few months and did other work... ...until the fall, when I felt like it was time to stop thinking and pondering (some would say stalling) and get on with it. Without stubs, the following gives a simplified high level view of how Solaris is built: An initially empty directory known as the proto, and referenced via the ROOT makefile macro is established to receive the files that make up the Solaris distribution. A top level setup rule creates the proto area, and performs operations needed to initialize the workspace so that the main build operations can be launched, such as copying needed header files into the proto area. Parallel builds are launched to build the kernel (usr/src/uts), libraries (usr/src/lib), and commands. The install makefile target builds each item and delivers a copy to the proto area. All libraries and executables link against the objects previously installed in the proto, implying the need to synchronize the order in which things are built. Subsequent passes run lint, and do packaging. Given this structure, the additions to use stub objects are: A new second proto area is established, known as the stub proto and referenced via the STUBROOT makefile macro. The stub proto has the same structure as the real proto, but is used to hold stub objects. All files in the real proto are delivered as part of the Solaris product. In contrast, the stub proto is used to build the product, and then thrown away. A new target is added to library Makefiles called stub. This rule builds the stub objects. The ld command is designed so that you can build a stub object using the same ld command line you'd use to build the real object, with the addition of a single -z stub option. This means that the makefile rules for building the stub objects are very similar to those used to build the real objects, and many existing makefile definitions can be shared between them. A new target is added to the Makefiles called stubinstall which delivers the stub objects built by the stub rule into the stub proto. These rules reuse much of existing plumbing used by the existing install rule. The setup rule runs stubinstall over the entire lib subtree as part of its initialization. All libraries and executables link against the objects in the stub proto rather than the main proto, and can therefore be built in parallel without any synchronization. There was no small way to try this that would yield meaningful results. I would have to take a leap of faith and edit approximately 1850 makefiles and 300 mapfiles first, trusting that it would all work out. Once the editing was done, I'd type make and see what happened. This took about 6 weeks to do, and there were many dark days when I'd question the entire project, or struggle to understand some of the many twisted and complex situations I'd uncover in the makefiles. I even found a couple of new issues that required changes to the new stub object related code I'd added to ld. With a substantial amount of encouragement and help from some key people in the Solaris group, I eventually got the editing done and stub objects for the entire workspace built. I found that my desktop system could build all the stub objects in the workspace in roughly a minute. This was great news, as it meant that use of the feature is effectively free — no one was likely to notice or care about the cost of building them. After another week of typing make, fixing whatever failed, and doing it again, I succeeded in getting a complete build! The next step was to remove all of the make rules and .WAIT statements dedicated to controlling the order in which libraries under usr/src/lib are built. This came together pretty quickly, and after a few more speed bumps, I had a workspace that built cleanly and looked like something you might actually be able to integrate someday. This was a significant milestone, but there was still much left to do. I turned to doing full nightly builds. Every type of build (open, closed, OpenSolaris, export, domestic) had to be tried. Each type failed in a new and unique way, requiring some thinking and rework. As things came together, I became aware of things that could have been done better, simpler, or cleaner, and those things also required some rethinking, the seeking of wisdom from others, and some rework. After another couple of weeks, it was in close to final form. My focus turned towards the end game and integration. This was a huge workspace, and needed to go back soon, before changes in the gate would made merging increasingly difficult. At this point, I knew that the stub objects had greatly simplified the makefile logic and uncovered a number of race conditions, some of which had been there for years. I assumed that the builds were faster too, so I did some builds intended to quantify the speedup in build time that resulted from this approach. It had never occurred to me that there might not be one. And so, I was very surprised to find that the wall clock build times for a stock ON workspace were essentially identical to the times for my stub library enabled version! This is why it is important to always measure, and not just to assume. One can tell from first principles, based on all those removed dependency rules in the library makefile, that the stub object version of ON gives dmake considerably more opportunities to overlap library construction. Some hypothesis were proposed, and shot down: Could we have disabled dmakes parallel feature? No, a quick check showed things being build in parallel. It was suggested that we might be I/O bound, and so, the threads would be mostly idle. That's a plausible explanation, but system stats didn't really support it. Plus, the timing between the stub and non-stub cases were just too suspiciously identical. Are our machines already handling as much parallelism as they are capable of, and unable to exploit these additional opportunities? Once again, we didn't see the evidence to back this up. Eventually, a more plausible and obvious reason emerged: We build the libraries and commands (usr/src/lib, usr/src/cmd) in parallel with the kernel (usr/src/uts). The kernel is the long leg in that race, and so, wall clock measurements of build time are essentially showing how long it takes to build uts. Although it would have been nice to post a huge speedup immediately, we can take solace in knowing that stub objects simplify the makefiles and reduce the possibility of race conditions. The next step in reducing build time should be to find ways to reduce or overlap the uts part of the builds. When that leg of the build becomes shorter, then the increased parallelism in the libs and commands will pay additional dividends. Until then, we'll just have to settle for simpler and more robust. And so, I integrated the link-editor support for creating stub objects into snv_153 (November 2010) with 6993877 ld should produce stub objects PSARC/2010/397 ELF Stub Objects followed by the work to convert the ON consolidation in snv_161 (February 2011) with 7009826 OSnet should use stub objects 4631488 lib/Makefile is too patient: .WAITs should be reduced This was a huge putback, with 2108 modified files, 8 new files, and 2 removed files. Due to the size, I was allowed a window after snv_160 closed in which to do the putback. It went pretty smoothly for something this big, a few more preexisting race conditions would be discovered and addressed over the next few weeks, and things have been quiet since then. Conclusions and Looking Forward Solaris has been built with stub objects since February. The fact that developers no longer specify the order in which libraries are built has been a big success, and we've eliminated an entire class of build error. That's not to say that there are no build races left in the ON makefiles, but we've taken a substantial bite out of the problem while generally simplifying and improving things. The introduction of a stub proto area has also opened some interesting new possibilities for other build improvements. As this article has become quite long, and as those uses do not involve stub objects, I will defer that discussion to a future article.

    Read the article

  • iphone presentModalViewController

    - by sandy
    Hi All, I have an app, inside that an UIViewController is attached on the UIWindow. on the view of UIViewController, i have added a button and a uiview_1 of size 100x80. this uiview_1 contains another uiview_2 as subview of same size and this uiview_2 contains a UIImageView or a UIlable at runtime (both UIImageView and UIlable are userinteraction enabled) now on the touch/click of UIImageView, i want to show a new view using presentModalViewController, the problem is the view is shown and using back button on the navigation bar i come to the previous/main screen. here the problem come in picture, now i am unable to touch the button or the UIImageView. both are not responding, but app is not crashed and nor frozen. what is wrong in that? Plz help in this... ----- EDIT: Approach First: SWVController *swvController = [[SWVController alloc] init]; UINavigationController *viewNavController = [[UINavigationController alloc] initWithRootViewController:swvController]; UIViewController *pushController = [[UIViewController alloc] init]; UIWindow *win = [[UIApplication sharedApplication] keyWindow]; [win addSubview:pushController.view]; [pushController presentModalViewController:viewNavController animated:YES]; In the swvController i have back button that calls the dismissModelViewController on click result is the Main screen ctrls are not responding to touch – sandy 3 hours ago Second approach: SWVController *swvController = [[SWVController alloc] init]; UINavigationController *viewNavController = [[UINavigationController alloc] initWithRootViewController:swvController]; UIViewController *pushController = [[UIViewController alloc] init]; [self addSubview:pushController.view]; [pushController presentModalViewController:viewNavController animated:YES]; In the swvController i have back button that calls the dismissModelViewController on click result is the swvController's back button on navbar is not responding – sandy 3 hours ago 3rd approach: SWVController *swvController = [[SWVController alloc] init]; UINavigationController *viewNavController = [[UINavigationController alloc] initWithRootViewController:swvController]; SampleAppAppDelegate *appdel = [[UIApplication sharedApplication] delegate]; [appdel.viewController presentModalViewController:viewNavController animated:YES]; result is working fine, but the problem is i dont want to use SampleAppAppDelegate,i want to give my small Uiview (100x80) as a ctrl to other person , where my ctrl will not able to get the AppDelegate of thet app at run time. – sandy 3 hours ago

    Read the article

  • Is Rails Metal (& Rack) a good way to implement a high traffic web service api?

    - by Greg
    I am working on a very typical web application. The main component of the user experience is a widget that a site owner would install on their front page. Every time their front page loads, the widget talks to our server and displays some of the data that returns. So there are two components to this web application: the front end UI that the site owner uses to configure their widget the back end component that responds to the widget's web api call Previously we had all of this running in PHP. Now we are experimenting with Rails, which is fantastic for #1 (the front end UI). The question is how to do #2, the back serving of widget information, efficiently. Obviously this is much higher load than the front end, since it is called every time the front page loads on one of our clients' websites. I can see two obvious approaches: A. Parallel Stack: Set up a parallel stack that uses something other than rails (e.g. our old PHP-based approach) but accesses the same database as the front end B. Rails Metal: Use Rails Metal/Rack to bypass the Rails routing mechanism, but keep the api call responder within the Rails app My main question: Is Rails/Metal a reasonable approach for something like this? But also... Will the overhead of loading the Rails environment still be too heavy? Is there a way to get even closer to the metal with Rails, bypassing most of the environment? Will Rails/Metal performance approach the perf of a similar task on straight PHP (just looking for ballpark here)? And... Is there a 'C' option that would be much better than both A and B? That is, something before going to the lengths of C code compiled to binary and installed as an nginx or apache module? Thanks in advance for any insights.

    Read the article

  • How do you handle 'SelectedItemChanged' events in a MVVM ViewModel?

    - by Travis
    I have some logic that depends upon two properties being set, as it executes when both properties have a value. For example: private void DoCalc() { if (string.IsNullOrEmpty(Property1) || string.IsNullOrEmpty(Property2)) return; Property3 = Property1 + " " + Property2; } That code would need to be executed every time Property1 or Property2 changed, but I'm having trouble figuring out how to do it in a stylistically acceptable manner. Here are the choices as I see them: 1) Call method from ViewModel I don't have a problem with this conceptually, as the logic is still in the ViewModel - I'm not a 'No code-behind' nazi. However, the 'trigger' logic (when either property changes) is still in the UI layer, which I don't love. The codebehind would look like this: void ComboBox_Property1_SelectedItemChanged(object sender, RoutedEventArgs e) { viewModel.DoCalc(); } 2) Call method from Property Setter This approach seems the most 'pure', but it also seems ugly, as if the logic is hidden. It would look like this: public string Property1 { get {return property1;} set { if (property1 != value) { property1 = value; NotifyPropertyChanged("Property1"); DoCalc(); } } } 3) Hook into the PropertyChanged event I'm now thinking this might be the right approach, but it feels weird to hook into the property changed event in the implementing viewmodel. It would look something like this: public ViewModel() { this.PropertyChanged += new PropertyChangedEventHandler(ViewModel_PropertyChanged); } void ViewModel_PropertyChanged(object sender, PropertyChangedEventArgs e) { if (e.PropertyName == "Property1" || e.PropertyName == "Property2") { DoCalc(); } } So, my question is, if you were browsing through some source code with that requirement, which approach would you prefer to see implemented (and why?). Thanks for any input.

    Read the article

  • Putting a versioned-but-not-via-source control project in source control

    - by Emilio
    I have some old code (an old but still maintained VB6 application) that from a source control point of view is the ultimate example of the plumber's plumbing (or cobbler's shoes). It's been version controlled by the approach of making a new directory for each version. Are there any major downsides to taking the following approach? Do the initial check-in of all files Erase all files from the working directory, then copy all files from the next version to the working directory Check them in Goto #2 until done Note that I have a general change log text file which I'd grab the comments from for each version I check in/commit. I don't have (or really care about at this point) comments on a per-file- basis. I don't really know at this point what files have changed between versions, and being lazy I figured I could avoid doing file compares between versions to find out, so that's why I'm taking the approach above. Not to mention that erasing all the files first allows file deletions to be detected. I specifically haven't mentioned which version control tool I'm using since I'm hoping (also assuming, but maybe very incorrectly) that the answer is fairly independent. When I use terms like "check-in" I use them in the general sense, not specific to a tool.

    Read the article

  • Postback problem when using URL Rewrite and 404.aspx

    - by salle55
    I'm using URL rewrite on my site to get URLs like: http://mysite.com/users/john instead of http://mysite.com/index.aspx?user=john To achive this extensionless rewrite with IIS6 and no access to the hosting-server I use the "404-approach". When a request that the server can't find, the mapped 404-page is executed, since this is a aspx-page the rewrite can be performed (I can setup the 404-mapping using the controlpanel on the hosting-service). This is the code in Global.asax: protected void Application_BeginRequest(object sender, EventArgs e) { string url = HttpContext.Current.Request.Url.AbsolutePath; if (url.Contains("404.aspx")) { string[] urlInfo404 = Request.Url.Query.ToString().Split(';'); if (urlInfo404.Length > 1) { string requestURL = urlInfo404[1]; if (requestURL.Contains("/users/")) { HttpContext.Current.RewritePath("~/index.aspx?user=" + GetPageID(requestURL)); StoreRequestURL(requestURL); } else if (requestURL.Contains("/picture/")) { HttpContext.Current.RewritePath("~/showPicture.aspx?pictureID=" + GetPageID(requestURL)); StoreRequestURL(requestURL); } } } } private void StoreRequestURL(string url) { url = url.Replace("http://", ""); url = url.Substring(url.IndexOf("/")); HttpContext.Current.Items["VirtualUrl"] = url; } private string GetPageID(string requestURL) { int idx = requestURL.LastIndexOf("/"); string id = requestURL.Substring(idx + 1); id = id.Replace(".aspx", ""); //Only needed when testing without the 404-approach return id; } And in Page_Load on my masterpage I set the correct URL in the action-attribute on the form-tag. protected void Page_Load(object sender, EventArgs e) { string virtualURL = (string)HttpContext.Current.Items["VirtualUrl"]; if (!String.IsNullOrEmpty(virtualURL)) { form1.Action = virtualURL; } } The rewrite works fine but when I perform a postback on the page the postback isn't executed, can this be solved somehow? The problem seems to be with the 404-approach because when I try without it (and loses the extensionless-feature) the postback works. That is when I request: http://mysite.com/users/john.aspx Can this be solved or is there any other solution that fulfil my requirements (IIS6, no serveraccess/ISAPI-filter and extensionless).

    Read the article

  • Which pattern should be used for editing properties with modal view controller on iPhone?

    - by Matthew Daugherty
    I am looking for a good pattern for performing basic property editing via a modal view on the iPhone. Assume I am putting together an application that works like the Contacts application. The "detail" view controller displays all of the contact's properties in a UITableView. When the UITableView goes into edit mode a disclosure icon is displayed in the cells. Clicking a cell causes a modal "editor" view controller to display a view that allows the user to modify the selected property. This view will often contain only a single text box or picker. The user clicks Cancel/Save and the "editor" view is dismissed and the "detail" view is updated. In this scenario, which view is responsible for updating the model? The "editor" view could update the property directly using Key-Value Coding. This appears in the CoreDataBooks example. This makes sense to me on some level because it treats the property as the model for the editor view controller. However, this is not the pattern suggested by the View Controller Programming Guide. It suggests that the "editor" view controller should define a protocol that the "detail" controller adopts. When the user indicates they are done with the edit, the "detail" view controller is called back with the entered value and it dismisses the "editor" view. Using this approach the "detail" controller updates the model. This approach seems problematic if you are using the same "editor" view for multiple properties since there is only a single call-back method. Would love to get some feedback on what approach works best.

    Read the article

< Previous Page | 34 35 36 37 38 39 40 41 42 43 44 45  | Next Page >