Search Results

Search found 8749 results on 350 pages for 'nullable types'.

Page 81/350 | < Previous Page | 77 78 79 80 81 82 83 84 85 86 87 88  | Next Page >

• Back button after doing posts on the same page

  - by user441521

  I have 3 pages to my site. The 1st page allows you to select a bunch of options. Those options get sent to the 2nd page to be displayed with some data about those options. From here I can click on a link to get to page 3 on 1 of the options. On page 3 I can create a new/edit/delete all on the same page where reloads come back to page 3. I want a "back" button on page 3 to go back to page 2, but retain the options it had from the original page 1 request. Page 1 has a bunch of check boxes which are passed to page 2 as arrays to the controller. My thought is that I have to pass these arrays (I converted them to lists) to page 3 (even thought page 3 directly doesn't need them) so that page 3 can use them in the back link to it can recreate the values page 1 sent to page 2 originally. I'm using asp.net MVC and when I pass the converted array it seems to convert it to the type instead of actually showing the values: "types=System.Collections.Generic.List" (where types is a List. Is this what is needed or are there other options to getting a "back" button in this case to go back to page 2. It's sort of a pain to pass information to page 3 that isn't really relevant to page 3 except the back button.

  Read the article

• Work Execution in EAM

  - by Annemarie Provisero

  ADVISOR WEBCAST: Work Execution in EAM PRODUCT FAMILY: Manufacturing Enterprise Asset Management July 5, 2011 at 8 am PT, 9 am MT, 11 am ET The purpose of this webcast is to discuss EAM Work Order Management. This one-hour session is ideal for Functional Users, System Administrators, Database Administrators, and Customers with a basic knowledge of EAM and who raise or manage work orders and related processes. During this webcast, Zar will cover the various types of work orders and look at all the related activities associated with work orders including: setup, operations, tasks, work order transactions, relationship and planning. TOPICS WILL INCLUDE: Work Order Types (Routine, Planned Maintenance, Rebuild, Easy) Work Order statuses and other important setups Operations and Tasks Relationships Work Order Transactions Work Order Planning A short, live demonstration (only if applicable) and question and answer period will be included. Oracle Advisor Webcasts are dedicated to building your awareness around our products and services. This session does not replace offerings from Oracle Global Support Services. Click here to register for this session ------------------------------------------------------------------------------------------------------------- The above webcast is a service of the E-Business Suite Communities in My Oracle Support. For more information on other webcasts, please reference the Oracle Advisor Webcast Schedule.Click here to visit the E-Business Communities in My Oracle Support Note that all links require access to My Oracle Support.

  Read the article

• SharePoint: UI for ordering list items

  - by svdoever

  SharePoint list items have in the the base Item template a field named Order. This field is not shown by default. SharePoint 2007, 2010 and 2013 have a possibility to specify the order in a UI, using the _layouts page: {SiteUrl}/_layouts/Reorder.aspx?List={ListId} In SharePoint 2010 and 2013 it is possible to add a custom action to a list. It is possible to add a custom action to order list items as follows (SharePoint 2010 description): Open SharePoint Designer 2010 Navigate to a list Select Custom Actions > List Item Menu Fill in the dialog box: Open List Settings > Advanced Settings > Content Types, and set Allow management of content types to No  On List Settings select Column Ordering This results in the following UI in the browser: Selecting the custom Order Items action (under List Tools > Items) results in: You can change your custom action in SharePoint designer. On the list screen in the bottom right corner you can find the custom action: We now need to modify the view to include the order by adding the Order field to the view, and sorting on the Order field. Problem is that the Order field is hidden. It is possible to modify the schema of the Order field to set the Hidden attribute to FALSE. If we don’t want to write code to do it and still get the required result it is also possible to modify the view through SharePoint Designer: Modify the code of the view: This results in: Note that if you change the view through the web UI these changes are partly lost. If this is a problem modify the Order field schema for the list.

  Read the article

• HTG Explains: How Internet Explorer Saves Your Passwords and How to Manage Them

  - by Taylor Gibb

  Privacy is very important when it comes to the digital world, but do you know exactly how your browser saves your passwords ? Read on to find out what goes on behind the scenes. When it comes to web applications, there are many different types of authentication. One of the types is called basic authentication, which is when you navigate to website and a dialog box opens to ask for a username and password. This also happens to be the authentication mechanism defined in the RFC for HTTP. You can see in the screen shot above that there is a check box that you can use to remember your credentials, but what does that do ? You might also ask yourself what happens if you are not using Basic authentication. There is another type of authentication called Form authentication, this is when the authentication is built right into the web application, like the How-To Geek website. This allows the Developer to control the look and feel of the form that we use to log in. How To Delete, Move, or Rename Locked Files in Windows HTG Explains: Why Screen Savers Are No Longer Necessary 6 Ways Windows 8 Is More Secure Than Windows 7

  Read the article

• Setting up a Google Analytics Campaign

  - by Ashfame

  I will be doing a bunch of things to give one of my projects (main app) a big initial push for which I will be building a few small Facebook apps which will help in promoting the main apps. Traffic from these apps need to be tracked individually. My main app will be posting on the walls when the user needs to be notified. Traffic from these posts need to be tracked. Traffic from emails sent by the main app need to be tracked, like different types of email. I need to track all of these & possibly a couple of more but I need to be sure that I build my campaign URLs correctly as I won't get another chance to fix it. Correct me where I am wrong: Campaign Name: Launch Campaign Medium: Email Campaign Source: Type1 or Type2 (I can break it down for different types of email, right?) For apps: Campaign Name: Launch Campaign Medium: Apps Campaign Source: App1 or App2 (I can break it down here for different apps, right?) What if I want to track two different links within a single email or a single app? Any way of tracking them individually too but still keeping to track them as one because tracking them as one makes more sense for me. Campaign Term & Campaign content is irrelevant in my case, or I can/should use them for something? And I will also be tracking traffic of different apps. Should I do more? Let me know if my scenario wasn't clear enough & I need to explain more.

  Read the article

• Structure of a .NET Assembly

  - by Om Talsania

  Assembly is the smallest unit of deployment in .NET Framework.When you compile your C# code, it will get converted into a managed module. A managed module is a standard EXE or DLL. This managed module will have the IL (Microsoft Intermediate Language) code and the metadata. Apart from this it will also have header information.The following table describes parts of a managed module.PartDescriptionPE HeaderPE32 Header for 32-bit PE32+ Header for 64-bit This is a standard Windows PE header which indicates the type of the file, i.e. whether it is an EXE or a DLL. It also contains the timestamp of the file creation date and time. It also contains some other fields which might be needed for an unmanaged PE (Portable Executable), but not important for a managed one. For managed PE, the next header i.e. CLR header is more importantCLR HeaderContains the version of the CLR required, some flags, token of the entry point method (Main), size and location of the metadata, resources, strong name, etc.MetadataThere can be many metadata tables. They can be categorized into 2 major categories.1. Tables that describe the types and members defined in your code2. Tables that describe the types and members referenced by your codeIL CodeMSIL representation of the C# code. At runtime, the CLR converts it into native instructions

  Read the article

• What’s ‘default’ for?

  - by Strenium

  Sometimes there's a need to communicate explicitly that value variable is yet to be "initialized" or in other words - we’ve never changed it from its' default value. Perhaps "initialized" is not the right word since a value type will always have some sort of value (even a nullable one) but it's just that - how do we tell? Of course an 'int' would be 0, an 'enum' would the first defined value of a given enum and so on – we sure can make this kind of check "by hand" but eventually it would get a bit messy. There's a more elegant way with a use of little-known functionality of: 'default'Let’s just say we have a simple Enum: Simple Enum namespace xxx.Common.Domain{    public enum SimpleEnum    {        White = 1,         Black = 2,         Red = 3    }}   In case below we set the value of the enum to ‘White’ which happens to be a first and therefore default value for the enum. So the snippet below will set value of the ‘isDefault’ Boolean to ‘true’. 'True' Case SimpleEnum simpleEnum = SimpleEnum.White;bool isDefault; /* btw this one is 'false' by default */ isDefault = simpleEnum == default(SimpleEnum) ? true : false; /* default value 'white' */   Here we set the value to ‘Red’ and ‘default’ will tell us whether or not this the default value for this enum type. In this case: ‘false’. 'False' Case simpleEnum = SimpleEnum.Red; /* change from default */isDefault = simpleEnum == default(SimpleEnum) ? true : false; /* value is not default any longer */ Same 'default' functionality can also be applied to DateTimes, value types and other custom types as well. Sweet ‘n Short. Happy Coding!

  Read the article

• Using ConcurrentQueue for thread-safe Performance Bookkeeping.

  - by Strenium

  Just a small tidbit that's sprung up today. I had to book-keep and emit diagnostics for the average thread performance in a highly-threaded code over a period of last X number of calls and no more. Need of the day: a thread-safe, self-managing stats container. Since .NET 4.0 introduced new thread-safe 'Collections.Concurrent' objects and I've been using them frequently - the one in particular seemed like a good fit for storing each threads' performance data - ConcurrentQueue. But I wanted to store only the most recent X# of calls and since the ConcurrentQueue currently does not support size constraint I had to come up with my own generic version which attempts to restrict usage to numeric types only: unfortunately there is no IArithmetic-like interface which constrains to only numeric types – so the constraints here here aren't as elegant as they could be. (Note the use of the Average() method, of course you can use others as well as make your own).   FIFO FixedSizedConcurrentQueue using System;using System.Collections.Concurrent;using System.Linq; namespace xxxxx.Data.Infrastructure{    [Serializable]    public class FixedSizedConcurrentQueue<T> where T : struct, IConvertible, IComparable<T>    {        private FixedSizedConcurrentQueue() { }         public FixedSizedConcurrentQueue(ConcurrentQueue<T> queue)        {            _queue = queue;        }         ConcurrentQueue<T> _queue = new ConcurrentQueue<T>();         public int Size { get { return _queue.Count; } }        public double Average { get { return _queue.Average(arg => Convert.ToInt32(arg)); } }         public int Limit { get; set; }        public void Enqueue(T obj)        {            _queue.Enqueue(obj);            lock (this)            {                T @out;                while (_queue.Count > Limit) _queue.TryDequeue(out @out);            }        }    } }   The usage case is straight-forward, in this case I’m using a FIFO queue of maximum size of 200 to store doubles to which I simply Enqueue() the calculated rates: Usage var RateQueue = new FixedSizedConcurrentQueue<double>(new ConcurrentQueue<double>()) { Limit = 200 }; /* greater size == longer history */   That’s about it. Happy coding!

  Read the article

• How does Game Salad compare with Cocos2D in terms of 2D game development?

  - by jih

  I want to make some 2d games for iOS. I first come across cocos2d and kobold but then wanted something more graphical for rapid prototyping. I then found Game Maker which doesn't support iOS but is fairly easy to learn and then found Game Salad which supports iOS as well as other platforms. I know this question has been ask before but I want to know in terms of the types of games I want to develop what an learning investment path would be best. The types of games genre I am interest are: Side scrollers Simple games like diamond dash or ninja fruits, shanghai, etc Old fashioned zelda or dragonquest type (nintendo fan here:-) 2d adventure RPG games (real time or turn based) Mystery turn based games like carmen sandiego, wizardry, myst etc. So now the question becomes for me becomes which game development environment should I invest my time in learning. Game Salad or cocos2d? To make that decision I was wondering if experienced game programmers and help with some pointers: It would seem game salad would be great for quickies being graphical but in terms of 2d platform games etc would there be speed/performance/feature penalties? Are there certain 2d games genre of the 4 above that Game salad is better at while certain type cocos2d would be better at?

  Read the article

• What sorts of tools make a Django Developer valuable? [closed]

  - by MrOodles

  I am a Django Consultant and I want to increase the value that I provide to clients. My first question was an epic failure according to the FAQ. So I'll try again before I delete it. What types of tools should a Django developer have in his tool belt to increase the value to the client? Would a collection of project templates be useful? Are there open-source project templates available that can be forked and altered? Is there a proper way to configure templates to include dependencies for certain types of projects? What about deployment scripts using tools like Puppet or Chef? Does it make a lot of sense to fork Django apps on GitHub and make contributions to open source projects there? Would clients percieve extra value in programmers that are contributing to open source projects? Are there industry best practices for implementing continuous integration in a Django project? I want the answer to be open ended, as I'm at the beginning of my research. I am curious to know what sorts of tools other Django consultants use on a daily and per-project basis, and how they use them.

  Read the article

• Returning a flexible datatype from a C++ function

  - by GavinH

  I'm developing for a legacy C++ application which uses ODBC for it's data access. Coming from a C# background, I really miss the ADO style of data access. I'm writing a wrapper (because we can't actually use ADO) to make our data access less painful. This means no char arrays, no manual text blob streaming, and no declaritive column binding. I'm struggling with how to store / return data values. In C# at least, you can declare an object and cast it to whatever (as long as the type is convertable). My current C++ solution is to use boost::any to store the data value in a custom DataColumnValue object. This class has conversion and assignment operators to the various types used in our app (more than 10). There's a bit of complexity here because if you store an int in the boost::any and try to boost::any_cast<long> you get a boost::bad_any_cast. Client objects shouldn't have to know how the value is stored internally. Does anyone have any experience trying to store / return values whose types are only known at runtime? Is there a better / cleaner way?

  Read the article

• The Freemium-Premium Puzzle

  The more time I spend thinking about the value of information, the more I found that digitalizing information significantly changed the 'information markets', potentially in an irreversible manner. The graph at the bottom outlines my current view. The existing business models tend to be the same in the digital and analogue information world, i.e. revenue is derived from a combination of consumers' payments and advertisement. Even monetizing 'meta-information' such as search engines isn't new. Just think of the once popular 'Who'sWho'. What really changed is the price-value ratio. The curve is pushed down, closer to the axis. You pay less for the same, or often even get more for less. If you recall the capabilities I described in relevance of information you will see that there are many additional features available for digital content compared to analogue content. I think this is a good 'blue ocean strategy' by combining existing capabilities in a new way. (Kim W.C. & Mauborgne, R. (2005) Blue Ocean Strategies. Boston: Harvard Business School Publishing.). In addition the different channels of digital information distribution significantly change the value of information. I will touch on this in one of my next blogs. Right now, many information providers started to offer 'freemium' content through digital channels, hoping to get a premium for the 'full' content. No freemium seems to take them out of business, because they are apparently no longer visible in today's most relevant channels of information consumption. But, the more freemium is provided, the lower the premium gets; a truly puzzling situation. To make it worse, channel providers increasingly regard information as a value adding and differentiating activity. Maybe new types of exclusive, strategic alliances will solve the puzzle, introducing new types of 'gate-keepers', which - to me - somehow does not match the spirit of the WWW and the generation Y's perception of information consumption and exchange.

  Read the article

• Has anyone used game salad before and how does it compare with cocos2d in terms of 2d game development

  - by jih

  First a short intro. I am new to the game development space and want to make some 2d games for iOS. I first come across cocos2d and kobold but then wanted something more graphical for rapid prototyping. I then found Game Maker which doesn't support iOS but is fairly easy to learn and then found Game Salad which supports iOS as well as other platforms. I know this question has been ask before but I want to know in terms of the types of games I want to develop what an learning investment path would be best. The types of games genre I am interest are: Side scrollers Simple games like diamond dash or ninja fruits, shanghai, etc Old fashioned zelda or dragonquest type (nintendo fan here:-) 2d adventure RPG games (real time or turn based) Mystery turn based games like carmen sandiego, wizardry, myst etc. So now the question becomes Which game development environment should I invest my time in learning. Game Salad or cocos2d? It would seem game salad would be great for quickies being graphical but in terms of 2d platform games etc would there be speed/performance/feature penalties? Are there certain 2d games genre of the 4 above that Game salad is better at while certain type cocos2d would be better at? Anyone with experience of both can share some pointers? Thanks. inexperienced jih

  Read the article

• Two Hidden NetBeans Keyboard Shortcuts for Opening & Toggling between Views

  - by Geertjan

  The following are two really basic shortcuts for working with NetBeans editor windows that will be added to the Keyboard Shortcuts card for NetBeans IDE 7.2: Ctrl-Alt-PgUp/PgDown: Shortcuts for switching between editor types (e.g. Source, Design, History buttons). Switching between the editor types is a frequent operation sometimes, e.g., when using GUI builder, and while it can be done easily via mouse, or from View | Editors menu, it is very handy to know the shortcuts as well. Ctrl-PgUp/PgDown: Similarly, these are shortcuts for switching to next/previous opened document (tab). Note this is not like Ctrl-Tab that cycles in the last used order, but going through the tabs as they appear in the editor. Both shortcuts should fit into the "Opening and Toggling between Views" section. These are important to mention on the card because they are not visible anywhere else in the UI (as there are no menu items like "Go to next/previous editor type" or "Go to next/previous document"). Reported by Tomas Pavek from the NetBeans Team, here: http://netbeans.org/bugzilla/show_bug.cgi?id=213815

  Read the article

• Type of AI to tackle this problem?

  - by user1154277

  I posted this on stackoverflow but want to get your recommendations as well as a user on overflow recommended I post it here. I'm going to say from the beginning that I am not a programmer, I have a cursory knowledge of different types of AI and am just a businessman building a web app. Anyways, the web app I am investing in to develop is for a hobby of mine. There are many part manufacturers, product manufacturers, upgrade and addon manufacturers etc. for hardware/products in this hobby's industry. Currently, I am in the process of building a crowd sourced platform for people who are knowledgeable to go in and mark up compatibility between those parts as its not always clear cut if they are for example: Manufacturer A makes a "A" class product, and manufacturer B makes upgrade/part that generally goes with class "A" products, but is for one reason or another not compatible with Manufacturer A's particular "A" class product. However, a good chunk (60%-70%) of the products/parts in the database can have their compatibility inferenced by their properties, For example: Part 1 is type "A" with "X" mm receiver and part 2 is also Type "A" with "X" mm interface and thus the two parts are compatible.. or Part 1 is a 8mm gear, thus all bushings of 8mm from any manufacturer is compatible with part 1. Further more, all gears can only have compatibility relationships in the database with bushing and gear boxes, but there can be no meaningful compatibility between a gear and a rail, or receiver since those parts don't interface. Now what I want is an AI to be able to learn from the decisions of the crowdsourced platform community and be able to inference compatibility for new parts/products based on their tagged attributes, what type of part they are etc. What would be the best form of AI to tackle this? I was thinking a Expert System, but explicitly engineering all of the knowledge rules would be daunting because of the complex relations between literally tens of thousands of parts, hundreds of part types and many manufacturers. Would a ANN (neural network) be ideal to learn from the many inputs/decisions of the crowdsource platform users? Any help/input is much appreciated.

  Read the article

• Efficiency of iterators and alternatives? [migrated]

  - by user48037

  I have the following code for my game tiles: std::vector<GameObject_Tile*>::iterator it; for(int y = 0; y < GAME_TILES_Y; y++) { for(int x = 0; x < GAME_TILES_X; x++) { for (it = gameTiles[x][y].tiles.begin() ; it != gameTiles[x][y].tiles.end(); ++it) {}}} tiles is: struct Game_Tile { // More specific object types will be added here eventually vector<GameObject_Tile*> tiles; }; My problem is that if I change the vector to just be a single GameObject_Tile* instead and remove the iterator line in the loop I go from about 200fps to 450fps. Some context: The vector/pointer only contains one object in both scenarios. I will eventually need to store multiple, but for testing I just set it to a single pointer. The loop goes through 2,300 objects each frame and draws them. I would like to point out that if I remove the Draw (not seen int he example) method, I gain about 30 frames in both scenarios, the issue is the iteration. So I am wondering why having this as a vector being looped through by an iterator (to get at a single object) is costing me over 200 frames when compared to it being a single pointer? The 200+ frames faster code is: std::vector<GameObject_Tile*>::iterator it; for(int y = 0; y < GAME_TILES_Y; y++) { for(int x = 0; x < GAME_TILES_X; x++) { //gameTiles[x][y].tiles is used as a pointer here instead of using *it }} tiles is: struct Game_Tile { // More specific object types will be added here eventually GameObject_Tile* tiles; };

  Read the article

• Survey Data Model - How to avoid EAV and excessive denormalization?

  - by AlexDPC

  Hi everyone, My database skills are mediocre at best and I have to design a data model for survey data. I have spent some thoughts on this and right now I feel that I am stuck between some kind of EAV model and a design involving hundreds of tables, each with hundreds of columns (and thousands of records). There must be a better way to do this and I hope that the wise folks on this forum can help me. I have already searched various forums, but I couldn't really find a solution. If it has already been given elsewhere, please excuse me and provide me with a link so I can read it up. Some assumptions about the data I have to deal with: Each survey consists of 1 to n questionnaires Each questionnaire consists of 100-2,000 questions (please ignore that 2,000 questions really sound like a lot to answer...) Questions can be of various types: multiple-choice, free text, a number (like age, income, percentages, ...) Each survey involves 10-200 countries (These are not the respondents. The respondents are actually people in the countries.) Depending on the type of questionnaire, each questionnaire is answered by 100-20,000 respondents per country. A country can adapt the questionnaires for a survey, i.e. add, remove or edit questions The data for one country is gathered in a separate database in that country. There is no possibility for online integration from the start. The data for all countries has to be integrated later. This means for example, if a country has deleted a question, that data must somehow be derived from what they sent in order to achieve a uniform design across all countries I will have to write the integration and cleaning software, which will need to work with every country's data In the end the data needs to be exported to flat files, one rectangular grid per country and questionnaire. I have already discussed this topic with people from various backgrounds and have not come to a good solution yet. I mainly got two kinds of opinions. The domain experts, who are used to working with flat files (spreadsheet-style) for data processing and analysis vote for a denormalized structure with loads of tables and columns as I described above (1 table per country and questionnaire). This sounds terrible to me, because I learned that wide tables are to be avoided, it will be annoying to determine which columns are actually in a table when working with it, the database will become cluttered with hundreds of tables (or I even need to set up multiple databases, each with a similar yet a bit differetn design), etc. O-O-programmers vote for a strongly "normalized" design, which would effectively lead to a central table containing all the answers from all respondents to all questions. This table would either need to contain a column of type sql_variant type or multiple answer columns with different types to store answers of different types (multiple choice, free text, ..). The former would essentially be a EAV model. I tend to follow Joe Celko here, who strongly discourages its use (he calls it OTLT or "One True Lookup Table"). The latter would imply that each row would contain null cells for the not applicable types by design. Another alternative I could think of would be to create one table per answer type, i.e., one for multiple-choice questions, one for free text questions, etc.. That's not so generic, it would lead to a lot of union joins, I think and I would have to add a table if a new answer type is invented. Sorry for boring you with all this text and thank you for your input! Cheers, Alex PS: I asked the same question here: http://www.eggheadcafe.com/community/aspnet/13/10242616/survey-data-model--how-to-avoid-eav-and-excessive-denormalization.aspx

  Read the article

• GCC error with variadic templates: "Sorry, unimplemented: cannot expand 'Identifier...' into a fixe

  - by Dennis

  While doing variadic template programming in C++0x on GCC, once in a while I get an error that says "Sorry, unimplemented: cannot expand 'Identifier...' into a fixed-length arugment list." If I remove the "..." in the code then I get a different error: "error: parameter packs not expanded with '...'". So if I have the "..." in, GCC calls that an error, and if I take the "..." out, GCC calls that an error too. The only way I have been able to deal with this is to completely rewrite the template metaprogram from scratch using a different approach, and (with luck) I eventually come up with code that doesn't cause the error. But I would really like to know what I was doing wrong. Despite Googling for it and despite much experimentation, I can't pin down what it is that I'm doing differently between variadic template code that does produce this error, and code that does not have the error. The wording of the error message seems to imply that the code should work according the C++0x standard, but that GCC doesn't support it yet. Or perhaps it is a compiler bug? Here's some code that produces the error. Note: I don't need you to write a correct implementation for me, but rather just to point out what is about my code that is causing this specific error // Used as a container for a set of types. template <typename... Types> struct TypePack { // Given a TypePack<T1, T2, T3> and T=T4, returns TypePack<T1, T2, T3, T4> template <typename T> struct Add { typedef TypePack<Types..., T> type; }; }; // Takes the set (First, Others...) and, while N > 0, adds (First) to TPack. // TPack is a TypePack containing between 0 and N-1 types. template <int N, typename TPack, typename First, typename... Others> struct TypePackFirstN { // sorry, unimplemented: cannot expand ‘Others ...’ into a fixed-length argument list typedef typename TypePackFirstN<N-1, typename TPack::template Add<First>::type, Others...>::type type; }; // The stop condition for TypePackFirstN: when N is 0, return the TypePack that has been built up. template <typename TPack, typename... Others> struct TypePackFirstN<0, TPack, Others...> //sorry, unimplemented: cannot expand ‘Others ...’ into a fixed-length argument list { typedef TPack type; }; EDIT: I've noticed that while a partial template instantiation that looks like does incur the error: template <typename... T> struct SomeStruct<1, 2, 3, T...> {}; Rewriting it as this does not produce an error: template <typename... T> struct SomeStruct<1, 2, 3, TypePack<T...>> {}; It seems that you can declare parameters to partial specializations to be variadic; i.e. this line is OK: template <typename... T> But you cannot actually use those parameter packs in the specialization, i.e. this part is not OK: SomeStruct<1, 2, 3, T... The fact that you can make it work if you wrap the pack in some other type, i.e. like this: SomeStruct<1, 2, 3, TypePack<T...>> to me implies that the declaration of the variadic parameter to a partial template specialization was successful, and you just can't use it directly. Can anyone confirm this?

  Read the article

• How to reserve public API to internal usage in .NET?

  - by mark

  Dear ladies and sirs. Let me first present the case, which will explain my question. This is going to be a bit long, so I apologize in advance :-). I have objects and collections, which should support the Merge API (it is my custom API, the signature of which is immaterial for this question). This API must be internal, meaning only my framework should be allowed to invoke it. However, derived types should be able to override the basic implementation. The natural way to implement this pattern as I see it, is this: The Merge API is declared as part of some internal interface, let us say IMergeable. Because the interface is internal, derived types would not be able to implement it directly. Rather they must inherit it from a common base type. So, a common base type is introduced, which would implement the IMergeable interface explicitly, where the interface methods delegate to respective protected virtual methods, providing the default implementation. This way the API is only callable by my framework, but derived types may override the default implementation. The following code snippet demonstrates the concept: internal interface IMergeable { void Merge(object obj); } public class BaseFrameworkObject : IMergeable { protected virtual void Merge(object obj) { // The default implementation. } void IMergeable.Merge(object obj) { Merge(obj); } } public class SomeThirdPartyObject : BaseFrameworkObject { protected override void Merge(object obj) { // A derived type implementation. } } All is fine, provided a single common base type suffices, which is usually true for non collection types. The thing is that collections must be mergeable as well. Collections do not play nicely with the presented concept, because developers do not develop collections from the scratch. There are predefined implementations - observable, filtered, compound, read-only, remove-only, ordered, god-knows-what, ... They may be developed from scratch in-house, but once finished, they serve wide range of products and should never be tailored to some specific product. Which means, that either: they do not implement the IMergeable interface at all, because it is internal to some product the scope of the IMergeable interface is raised to public and the API becomes open and callable by all. Let us refer to these collections as standard collections. Anyway, the first option screws my framework, because now each possible standard collection type has to be paired with the respective framework version, augmenting the standard with the IMergeable interface implementation - this is so bad, I am not even considering it. The second option breaks the framework as well, because the IMergeable interface should be internal for a reason (whatever it is) and now this interface has to open to all. So what to do? My solution is this. make IMergeable public API, but add an extra parameter to the Merge method, I call it a security token. The interface implementation may check that the token references some internal object, which is never exposed to the outside. If this is the case, then the method was called from within the framework, otherwise - some outside API consumer attempted to invoke it and so the implementation can blow up with a SecurityException. Here is the modified code snippet demonstrating this concept: internal static class InternalApi { internal static readonly object Token = new object(); } public interface IMergeable { void Merge(object obj, object token); } public class BaseFrameworkObject : IMergeable { protected virtual void Merge(object obj) { // The default implementation. } public void Merge(object obj, object token) { if (!object.ReferenceEquals(token, InternalApi.Token)) { throw new SecurityException("bla bla bla"); } Merge(obj); } } public class SomeThirdPartyObject : BaseFrameworkObject { protected override void Merge(object obj) { // A derived type implementation. } } Of course, this is less explicit than having an internally scoped interface and the check is moved from the compile time to run time, yet this is the best I could come up with. Now, I have a gut feeling that there is a better way to solve the problem I have presented. I do not know, may be using some standard Code Access Security features? I have only vague understanding of it, but can LinkDemand attribute be somehow related to it? Anyway, I would like to hear other opinions. Thanks.

  Read the article

• Kendo Grid: Foreign Key Dropdown does not update grid cell after update

  - by JookyDFW

  I have a Kendo MVC grid that contains a nullable property (short) that is bound as a foreign key and uses a dropdown list as an editor template. I am also using inline editing. When the property value is null, the dropdown list selected value does not get set into the grid cell after the update button is clicked. This works fine if incell editing is used. I am looking for a workaround that will solve my problem. I am including a stripped down version of my code below Everything works if the nullable value is set to a non-null value. GRID @(Html.Kendo().Grid<AssetViewModel>() .Name("DealAssets") .Columns(c => { c.Bound(x => x.Name); c.ForeignKey(x => x.AssetTypeID, (IEnumerable<SelectListItem>)ViewBag.AssetTypeList, "Value", "Text"); c.ForeignKey(x => x.SeniorityTypeID, seniorityTypeList, "Value", "Text").EditorTemplateName("GridNullableForeignKey"); c.ForeignKey(x => x.RateBaseID, rateBaseList, "Value", "Text").EditorTemplateName("GridNullableForeignKey"); ; c.Command(m => { m.Edit(); m.Destroy(); }); }) .ToolBar(toolbar => toolbar.Create().Text("Add New Asset")) .Editable(x => x.Mode(GridEditMode.InLine)) .DataSource(ds => ds .Ajax() .Model(model => model.Id(request => request.ID)) .Read(read => read.Action("ReadAssets", "Deal", new { id = Model.ID })) .Create(create => create.Action("CreateAsset", "Deal", new { currentDealID = Model.ID })) .Update(update => update.Action("UpdateAsset", "Deal")) .Destroy(destroy => destroy.Action("DeleteAsset", "Deal")) ) ) EDITOR TEMPLATE @model short? @{ var controlName = ViewData.TemplateInfo.GetFullHtmlFieldName(""); } @( Html.Kendo().DropDownListFor(m => m) .Name(controlName) .OptionLabel("- Please select -") .BindTo((SelectList)ViewData[ViewData.TemplateInfo.GetFullHtmlFieldName("") + "_Data"]) ) UPDATE ACTION public ActionResult UpdateAsset([DataSourceRequest] DataSourceRequest request, int ID) { var dealAsset = DataContext.DealAssets.SingleOrDefault(o => o.ID == ID); if (dealAsset != null) { if (TryUpdateModel(dealAsset.Asset, new[] {"Name","AssetTypeID","SeniorityTypeID","RateBaseID" })) { DataContext.SaveChanges(); } } return Json(new[] { new AssetViewModel(dealAsset) }.ToDataSourceResult(request, ModelState), JsonRequestBehavior.AllowGet); }

  Read the article

• Applying ServiceKnownTypeAttribute to WCF service with Spring

  - by avidgoffer

  I am trying to apply the ServiceKnownTypeAttribute to my WCF Service but keep getting the error below my config. Does anyone have any ideas? <object id="HHGEstimating" type="Spring.ServiceModel.ServiceExporter, Spring.Services"> <property name="TargetName" value="HHGEstimatingHelper"/> <property name="Name" value="HHGEstimating"/> <property name="Namespace" value="http://www.igcsoftware.com/HHGEstimating"/> <property name="TypeAttributes"> <list> <ref local="wcfErrorBehavior"/> <ref local="wcfSilverlightFaultBehavior"/> <object type="System.ServiceModel.ServiceKnownTypeAttribute, System.ServiceModel"> <constructor-arg name="type" value="IGCSoftware.HHG.Business.UserControl.AtlasUser, IGCSoftware.HHG.Business"/> </object> </list> </property> Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: Spring.Objects.Factory.ObjectCreationException: Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [ObjectCreationException: Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46'] Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolveInnerObjectDefinition(String name, String innerObjectName, String argumentName, IObjectDefinition definition, Boolean singletonOwner) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:300 Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolvePropertyValue(String name, IObjectDefinition definition, String argumentName, Object argumentValue) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:150 Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolveValueIfNecessary(String name, IObjectDefinition definition, String argumentName, Object argumentValue) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:112 Spring.Objects.Factory.Config.ManagedList.Resolve(String objectName, IObjectDefinition definition, String propertyName, ManagedCollectionElementResolver resolver) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Config\ManagedList.cs:126 Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolvePropertyValue(String name, IObjectDefinition definition, String argumentName, Object argumentValue) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:201 Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolveValueIfNecessary(String name, IObjectDefinition definition, String argumentName, Object argumentValue) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:112 Spring.Objects.Factory.Support.AbstractAutowireCapableObjectFactory.ApplyPropertyValues(String name, RootObjectDefinition definition, IObjectWrapper wrapper, IPropertyValues properties) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractAutowireCapableObjectFactory.cs:373 Spring.Objects.Factory.Support.AbstractAutowireCapableObjectFactory.PopulateObject(String name, RootObjectDefinition definition, IObjectWrapper wrapper) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractAutowireCapableObjectFactory.cs:563 Spring.Objects.Factory.Support.AbstractAutowireCapableObjectFactory.ConfigureObject(String name, RootObjectDefinition definition, IObjectWrapper wrapper) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractAutowireCapableObjectFactory.cs:1844 Spring.Objects.Factory.Support.AbstractAutowireCapableObjectFactory.InstantiateObject(String name, RootObjectDefinition definition, Object[] arguments, Boolean allowEagerCaching, Boolean suppressConfigure) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractAutowireCapableObjectFactory.cs:918 Spring.Objects.Factory.Support.AbstractObjectFactory.CreateAndCacheSingletonInstance(String objectName, RootObjectDefinition objectDefinition, Object[] arguments) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractObjectFactory.cs:2120 Spring.Objects.Factory.Support.AbstractObjectFactory.GetObjectInternal(String name, Type requiredType, Object[] arguments, Boolean suppressConfigure) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractObjectFactory.cs:2046 Spring.Objects.Factory.Support.DefaultListableObjectFactory.PreInstantiateSingletons() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\DefaultListableObjectFactory.cs:505 Spring.Context.Support.AbstractApplicationContext.Refresh() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\AbstractApplicationContext.cs:911 _dynamic_Spring.Context.Support.XmlApplicationContext..ctor(Object[] ) +197 Spring.Reflection.Dynamic.SafeConstructor.Invoke(Object[] arguments) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Reflection\Dynamic\DynamicConstructor.cs:116 Spring.Context.Support.RootContextInstantiator.InvokeContextConstructor(ConstructorInfo ctor) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextHandler.cs:550 Spring.Context.Support.ContextInstantiator.InstantiateContext() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextHandler.cs:494 Spring.Context.Support.ContextHandler.InstantiateContext(IApplicationContext parentContext, Object configContext, String contextName, Type contextType, Boolean caseSensitive, String[] resources) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextHandler.cs:330 Spring.Context.Support.ContextHandler.Create(Object parent, Object configContext, XmlNode section) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextHandler.cs:280 [ConfigurationErrorsException: Error creating context 'spring.root': Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46'] System.Configuration.BaseConfigurationRecord.EvaluateOne(String[] keys, SectionInput input, Boolean isTrusted, FactoryRecord factoryRecord, SectionRecord sectionRecord, Object parentResult) +202 System.Configuration.BaseConfigurationRecord.Evaluate(FactoryRecord factoryRecord, SectionRecord sectionRecord, Object parentResult, Boolean getLkg, Boolean getRuntimeObject, Object& result, Object& resultRuntimeObject) +1061 System.Configuration.BaseConfigurationRecord.GetSectionRecursive(String configKey, Boolean getLkg, Boolean checkPermission, Boolean getRuntimeObject, Boolean requestIsHere, Object& result, Object& resultRuntimeObject) +1431 System.Configuration.BaseConfigurationRecord.GetSection(String configKey, Boolean getLkg, Boolean checkPermission) +56 System.Configuration.BaseConfigurationRecord.GetSection(String configKey) +8 System.Web.Configuration.HttpConfigurationSystem.GetApplicationSection(String sectionName) +45 System.Web.Configuration.HttpConfigurationSystem.GetSection(String sectionName) +49 System.Web.Configuration.HttpConfigurationSystem.System.Configuration.Internal.IInternalConfigSystem.GetSection(String configKey) +6 System.Configuration.ConfigurationManager.GetSection(String sectionName) +78 Spring.Util.ConfigurationUtils.GetSection(String sectionName) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Util\ConfigurationUtils.cs:69 Spring.Context.Support.ContextRegistry.InitializeContextIfNeeded() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextRegistry.cs:340 Spring.Context.Support.ContextRegistry.GetContext() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextRegistry.cs:206 Spring.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(String reference, Uri[] baseAddresses) in l:\projects\spring-net\trunk\src\Spring\Spring.Services\ServiceModel\Activation\ServiceHostFactory.cs:66 System.ServiceModel.HostingManager.CreateService(String normalizedVirtualPath) +11687036 System.ServiceModel.HostingManager.ActivateService(String normalizedVirtualPath) +42 System.ServiceModel.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath) +479 [ServiceActivationException: The service '/HHGEstimating.svc' cannot be activated due to an exception during compilation. The exception message is: Error creating context 'spring.root': Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46'.] System.ServiceModel.AsyncResult.End(IAsyncResult result) +11592858 System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result) +194 System.ServiceModel.Activation.HostedHttpRequestAsyncResult.ExecuteSynchronous(HttpApplication context, Boolean flowContext) +176 System.ServiceModel.Activation.HttpModule.ProcessRequest(Object sender, EventArgs e) +275 System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +68 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75

  Read the article

• Cannot implicitly convert type 'System.Linq.IQueryable<int>' to 'int?'

  - by Aneef

  Hi this is my code var cityList = from country in doc.Element("result").Element("cities").Descendants("city") select new { Name = country.Element("name").Value, Code = country.Element("code").Value, CountryCode = int.Parse(country.Element("countrycode").Value) }; foreach(var citee in cityList) { City city = new City(); city.CountryID = from cnt in db.Countries where cnt.DOTWInternalID == citee.CountryCode select cnt.ID; } Im getting an error on the second query as the title of this post, i tried converting to int, to nullable int nothing worked? help me guys Thanks,

  Read the article

• The parameters dictionary contains a null entry for parameter

  - by ognjenb

  <%using (Html.BeginForm("OrderDevice", "ImportXML", FormMethod.Post)) { %> <table id="OrderDevices" class="data-table"> <tr> <th> DeviceId </th> <th> Id </th> <th> OrderId </th> </tr> <% foreach (var item in Model) { %> <tr> <td> <input readonly="readonly" class="" id="DeviceId" type="text" name="<%= Html.Encode(item.DeviceId) %>" value="<%= Html.Encode(item.DeviceId) %>" style="width: 61px" /> </td> <td> <input readonly="readonly" class="" id="c" type="text" name= "<%= Html.Encode(item.Id) %>" value=" <%= Html.Encode(item.Id) %>" style="width: 50px" /> </td> <td> <input readonly="readonly" class="" id="OrderId" type="text" name= " <%= Html.Encode(item.OrderId) %>" value="<%= Html.Encode(item.OrderId) %> " style="width: 49px" /> </td> </tr> <% } %> </table> <input type="submit" value="Create"/> <%} %> My controller action: [AcceptVerbs(HttpVerbs.Post)] public ActionResult OrderDevice(int id) { try { // TODO: Add insert logic here orderdevice ord = new orderdevice(); ord.Id = System.Convert.ToInt32(Request.Form["Id"]); ord.OrderId = System.Convert.ToInt32(Request.Form["OrderId"]); ord.DeviceId = System.Convert.ToInt32(Request.Form["DeviceId"]); XMLEntities.AddToorderdevice(ord); XMLEntities.SaveChanges(); return RedirectToAction("Index"); } catch { return View("Index"); } } When post a form I have this error: The parameters dictionary contains a null entry for parameter 'id' of non-nullable type 'System.Int32' for method 'System.Web.Mvc.ActionResult OrderDevice(Int32)' in 'MvcKVteam.Controllers.ImportXMLController'. An optional parameter must be a reference type, a nullable type, or be declared as an optional parameter. Parameter name: parameters How fix it?

  Read the article

• JPA : optimize EJB-QL query involving large many-to-many join table

  - by Fabien

  Hi all. I'm using Hibernate Entity Manager 3.4.0.GA with Spring 2.5.6 and MySql 5.1. I have a use case where an entity called Artifact has a reflexive many-to-many relation with itself, and the join table is quite large (1 million lines). As a result, the HQL query performed by one of the methods in my DAO takes a long time. Any advice on how to optimize this and still use HQL ? Or do I have no choice but to switch to a native SQL query that would perform a join between the table ARTIFACT and the join table ARTIFACT_DEPENDENCIES ? Here is the problematic query performed in the DAO : @SuppressWarnings("unchecked") public List<Artifact> findDependentArtifacts(Artifact artifact) { Query query = em.createQuery("select a from Artifact a where :artifact in elements(a.dependencies)"); query.setParameter("artifact", artifact); List<Artifact> list = query.getResultList(); return list; } And the code for the Artifact entity : package com.acme.dependencytool.persistence.model; import java.util.ArrayList; import java.util.List; import javax.persistence.CascadeType; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.JoinColumn; import javax.persistence.JoinTable; import javax.persistence.ManyToMany; import javax.persistence.Table; import javax.persistence.UniqueConstraint; @Entity @Table(name = "ARTIFACT", uniqueConstraints={@UniqueConstraint(columnNames={"GROUP_ID", "ARTIFACT_ID", "VERSION"})}) public class Artifact { @Id @GeneratedValue @Column(name = "ID") private Long id = null; @Column(name = "GROUP_ID", length = 255, nullable = false) private String groupId; @Column(name = "ARTIFACT_ID", length = 255, nullable = false) private String artifactId; @Column(name = "VERSION", length = 255, nullable = false) private String version; @ManyToMany(cascade=CascadeType.ALL, fetch=FetchType.EAGER) @JoinTable( name="ARTIFACT_DEPENDENCIES", joinColumns = @JoinColumn(name="ARTIFACT_ID", referencedColumnName="ID"), inverseJoinColumns = @JoinColumn(name="DEPENDENCY_ID", referencedColumnName="ID") ) private List<Artifact> dependencies = new ArrayList<Artifact>(); public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getGroupId() { return groupId; } public void setGroupId(String groupId) { this.groupId = groupId; } public String getArtifactId() { return artifactId; } public void setArtifactId(String artifactId) { this.artifactId = artifactId; } public String getVersion() { return version; } public void setVersion(String version) { this.version = version; } public List<Artifact> getDependencies() { return dependencies; } public void setDependencies(List<Artifact> dependencies) { this.dependencies = dependencies; } } Thanks in advance. EDIT 1 : The DDLs are generated automatically by Hibernate EntityMananger based on the JPA annotations in the Artifact entity. I have no explicit control on the automaticaly-generated join table, and the JPA annotations don't let me explicitly set an index on a column of a table that does not correspond to an actual Entity (in the JPA sense). So I guess the indexing of table ARTIFACT_DEPENDENCIES is left to the DB, MySQL in my case, which apparently uses a composite index based on both clumns but doesn't index the column that is most relevant in my query (DEPENDENCY_ID). mysql describe ARTIFACT_DEPENDENCIES; +---------------+------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +---------------+------------+------+-----+---------+-------+ | ARTIFACT_ID | bigint(20) | NO | MUL | NULL | | | DEPENDENCY_ID | bigint(20) | NO | MUL | NULL | | +---------------+------------+------+-----+---------+-------+ EDIT 2 : When turning on showSql in the Hibernate session, I see many occurences of the same type of SQL query, as below : select dependenci0_.ARTIFACT_ID as ARTIFACT1_1_, dependenci0_.DEPENDENCY_ID as DEPENDENCY2_1_, artifact1_.ID as ID1_0_, artifact1_.ARTIFACT_ID as ARTIFACT2_1_0_, artifact1_.GROUP_ID as GROUP3_1_0_, artifact1_.VERSION as VERSION1_0_ from ARTIFACT_DEPENDENCIES dependenci0_ left outer join ARTIFACT artifact1_ on dependenci0_.DEPENDENCY_ID=artifact1_.ID where dependenci0_.ARTIFACT_ID=? Here's what EXPLAIN in MySql says about this type of query : mysql explain select dependenci0_.ARTIFACT_ID as ARTIFACT1_1_, dependenci0_.DEPENDENCY_ID as DEPENDENCY2_1_, artifact1_.ID as ID1_0_, artifact1_.ARTIFACT_ID as ARTIFACT2_1_0_, artifact1_.GROUP_ID as GROUP3_1_0_, artifact1_.VERSION as VERSION1_0_ from ARTIFACT_DEPENDENCIES dependenci0_ left outer join ARTIFACT artifact1_ on dependenci0_.DEPENDENCY_ID=artifact1_.ID where dependenci0_.ARTIFACT_ID=1; +----+-------------+--------------+--------+-------------------+-------------------+---------+---------------------------------------------+------+-------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+--------------+--------+-------------------+-------------------+---------+---------------------------------------------+------+-------+ | 1 | SIMPLE | dependenci0_ | ref | FKEA2DE763364D466 | FKEA2DE763364D466 | 8 | const | 159 | | | 1 | SIMPLE | artifact1_ | eq_ref | PRIMARY | PRIMARY | 8 | dependencytooldb.dependenci0_.DEPENDENCY_ID | 1 | | +----+-------------+--------------+--------+-------------------+-------------------+---------+---------------------------------------------+------+-------+ EDIT 3 : I tried setting the FetchType to LAZY in the JoinTable annotation, but I then get the following exception : Hibernate: select artifact0_.ID as ID1_, artifact0_.ARTIFACT_ID as ARTIFACT2_1_, artifact0_.GROUP_ID as GROUP3_1_, artifact0_.VERSION as VERSION1_ from ARTIFACT artifact0_ where artifact0_.GROUP_ID=? and artifact0_.ARTIFACT_ID=? 51545 [btpool0-2] ERROR org.hibernate.LazyInitializationException - failed to lazily initialize a collection of role: com.acme.dependencytool.persistence.model.Artifact.dependencies, no session or session was closed org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.acme.dependencytool.persistence.model.Artifact.dependencies, no session or session was closed at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:380) at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:372) at org.hibernate.collection.AbstractPersistentCollection.readSize(AbstractPersistentCollection.java:119) at org.hibernate.collection.PersistentBag.size(PersistentBag.java:248) at com.acme.dependencytool.server.DependencyToolServiceImpl.createArtifactViewBean(DependencyToolServiceImpl.java:93) at com.acme.dependencytool.server.DependencyToolServiceImpl.createArtifactViewBean(DependencyToolServiceImpl.java:109) at com.acme.dependencytool.server.DependencyToolServiceImpl.search(DependencyToolServiceImpl.java:48) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:527) at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:166) at com.google.gwt.user.server.rpc.RemoteServiceServlet.doPost(RemoteServiceServlet.java:86) at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:362) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:729) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.handler.RequestLogHandler.handle(RequestLogHandler.java:49) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.Server.handle(Server.java:324) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:505) at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:843) at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:647) at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:205) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:380) at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:395) at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:488)

  Read the article

• I am getting an error with a oneToMany association when using annotations with gilead for hibernate

  - by user286630

  Hello Guys I'm using Gilead to persist my entities in my GWT project, im using hibernate annotations aswell. my problem is on my onetomany association.this is my User class that holds a reference to a list of FileLocations @Entity @Table(name = "yf_user_table") public class YFUser implements Serializable { @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "user_id",nullable = false) private int userId; @Column(name = "username") private String username; @Column(name = "password") private String password; @Column(name = "email") private String email; @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY) @JoinColumn(name="USER_ID") private List fileLocations = new ArrayList(); This is my file location class @Entity @Table(name = "fileLocationTable") public class FileLocation implements Serializable { @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "locationId", updatable = false, nullable = false) private int ieId; @Column (name = "location") private String location; @ManyToOne(fetch=FetchType.LAZY) @JoinColumn(name="USER_ID", nullable=false) private YFUser uploadedUser; When i persist this data in a normal desktop application, it works fine , creates the tables and i can add and store data to it. but when i try to persist the data in my gwt application i get errors i will show them lower. this is my ServiceImpl class that extends PersistentRemoteService. public class TestServiceImpl extends PersistentRemoteService implements TestService { public static final String SESSION_USER = "UserWithinSession"; public TestServiceImpl(){ HibernateUtil util = new HibernateUtil(); util.setSessionFactory(com.example.server.HibernateUtil .getSessionFactory()); PersistentBeanManager pbm = new PersistentBeanManager(); pbm.setPersistenceUtil(util); pbm.setProxyStore(new StatelessProxyStore()); setBeanManager(pbm); } @Override public String registerUser(String username, String password, String email) { Session session = com.example.server.HibernateUtil.getSessionFactory().getCurrentSession(); session.beginTransaction(); YFUser newUser = new YFUser(); newUser.setUsername(username);newUser.setPassword(password);newUser.setEmail(email); session.save(newUser); session.getTransaction().commit(); return "Thank you For registering "+ username; } this is the error that im am getting. the error goes away when i remove my onetoManyRelationship and builds my session factory when i put it in , it on the line of buildsessionfactory in hibernate Util that it throws this exception. my hibernate util class is ok also. this is the error java.lang.NoSuchMethodError: javax.persistence.OneToMany.orphanRemoval()Z Mar 24, 2010 10:03:22 PM org.hibernate.cfg.annotations.Version <clinit> INFO: Hibernate Annotations 3.5.0-Beta-4 Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Environment <clinit> INFO: Hibernate 3.5.0-Beta-4 Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Environment <clinit> INFO: hibernate.properties not found Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Environment buildBytecodeProvider INFO: Bytecode provider name : javassist Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Environment <clinit> INFO: using JDK 1.4 java.sql.Timestamp handling Mar 24, 2010 10:03:22 PM org.hibernate.annotations.common.Version <clinit> INFO: Hibernate Commons Annotations 3.2.0-SNAPSHOT Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Configuration configure INFO: configuring from resource: /hibernate.cfg.xml Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Configuration getConfigurationInputStream INFO: Configuration resource: /hibernate.cfg.xml Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Configuration doConfigure INFO: Configured SessionFactory: null Mar 24, 2010 10:03:22 PM org.hibernate.cfg.search.HibernateSearchEventListenerRegister enableHibernateSearch INFO: Unable to find org.hibernate.search.event.FullTextIndexEventListener on the classpath. Hibernate Search is not enabled. Mar 24, 2010 10:03:22 PM org.hibernate.cfg.AnnotationBinder bindClass INFO: Binding entity from annotated class: com.example.client.Entity1 Mar 24, 2010 10:03:22 PM org.hibernate.cfg.annotations.EntityBinder bindTable INFO: Bind entity com.example.client.Entity1 on table entityTable1 Mar 24, 2010 10:03:22 PM org.hibernate.cfg.AnnotationBinder bindClass INFO: Binding entity from annotated class: com.example.client.YFUser Mar 24, 2010 10:03:22 PM org.hibernate.cfg.annotations.EntityBinder bindTable INFO: Bind entity com.example.client.YFUser on table yf_user_table Initial SessionFactory creation failed.java.lang.NoSuchMethodError: javax.persistence.OneToMany.orphanRemoval()Z [WARN] Nested in javax.servlet.ServletException: init: java.lang.ExceptionInInitializerError at com.example.server.HibernateUtil.<clinit>(HibernateUtil.java:38) at com.example.server.TestServiceImpl.<init>(TestServiceImpl.java:29) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39 ) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at java.lang.Class.newInstance0(Class.java:355) at java.lang.Class.newInstance(Class.java:308) at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) at org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java:339) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:463) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:362) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:729) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.handler.RequestLogHandler.handle(RequestLogHandler.java:49) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.Server.handle(Server.java:324) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:505) at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:843) at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:647) at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:380) at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:396) at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:488) Caused by: java.lang.NoSuchMethodError: javax.persistence.OneToMany.orphanRemoval()Z at org.hibernate.cfg.AnnotationBinder.processElementAnnotations(AnnotationBinder.java:1642) at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:772) at org.hibernate.cfg.AnnotationConfiguration.processArtifactsOfType(AnnotationConfiguration.java:629) at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:350) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1373) at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:973) at com.example.server.HibernateUtil.<clinit>(HibernateUtil.java:33) ... 26 more [WARN] Nested in java.lang.ExceptionInInitializerError: java.lang.NoSuchMethodError: javax.persistence.OneToMany.orphanRemoval()Z at org.hibernate.cfg.AnnotationBinder.processElementAnnotations(AnnotationBinder.java:1642) at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:772) at org.hibernate.cfg.AnnotationConfiguration.processArtifactsOfType(AnnotationConfiguration.java:629) at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:350) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1373) at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:973) at com.example.server.HibernateUtil.<clinit>(HibernateUtil.java:33) at com.example.server.TestServiceImpl.<init>(TestServiceImpl.java:29) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at java.lang.Class.newInstance0(Class.java:355) at java.lang.Class.newInstance(Class.java:308) at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) at org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java:339) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:463) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:362) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:729) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.handler.RequestLogHandler.handle(RequestLogHandler.java:49) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.Server.handle(Server.java:324) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:505) at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:843) at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:647) at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:380) at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:396) at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:488)

  Read the article

< Previous Page | 77 78 79 80 81 82 83 84 85 86 87 88  | Next Page >