Search Results

Search found 1806 results on 73 pages for 'lazy evaluation'.

Page 11/73 | < Previous Page | 7 8 9 10 11 12 13 14 15 16 17 18  | Next Page >

  • What is "Call By Name"?

    - by forellana
    Hi to everyone! I'm working in a homework, and the professor asked me to implement the evaluation strategy called "call by name" in scheme in a certain language that we developed and he gave us an example at http://www.scala-lang.org/node/138 in the scala language, but i don't understand in what consists the call by name evaluation strategy? what differences it has with call by need? thanks, greetings

    Read the article

  • How to lazy process an xml documentwith hexpat?

    - by Florian
    In my search for a haskell library that can process large (300-1000mb) xml files i came across hexpat. There is an example in the Haskell Wiki that claims to -- Process document before handling error, so we get lazy processing. For testing purposes i have redirected the output to /dev/null and throw a 300mb file at it. Memory consumption kept rising until i had to kill the process. Now i removed the error handling from the process function: process :: String -> IO () process filename = do inputText <- L.readFile filename let (xml, mErr) = parse defaultParseOptions inputText :: (UNode String, Maybe XMLParseError) hFile <- openFile "/dev/null" WriteMode L.hPutStr hFile $ format xml hClose hFile return () As a result the function now uses constant memory. Why does the error handling result in massive memory consumption? As far as i understand xml and mErr are two seperate unevaluated thunks after the call to parse. Does format xml evaluate xml and build the evaluation tree of 'mErr'? If yes is there a way to handle the error while using constant memory? http://www.haskell.org/haskellwiki/Hexpat/

    Read the article

  • Lazy loading is not working for one to many

    - by Shire
    Any 1-M that use the primary key of the parent table, but any 1-M that uses a different column does not work. It generates the SQL correctly, but put the value of the key into the SQL instead of the column value I want. Example mapping: public TemplateMap() { Table("IMPORT"); LazyLoad(); Id(x => x.ImportId).Column("IMPORT_ID").GeneratedBy.Assigned(); Map(x => x.ImportSetId).Column("IMPORTSET_ID"); HasMany(x => x.GoodChildren) .Access.CamelCaseField() .KeyColumns.Add("IMPORT_ID") .Cascade.Delete() .Inverse(); HasMany(x => x.BadChildren) .Access.CamelCaseField() .KeyColumns.Add("IMPORTSET_ID") .Cascade.Delete() .Inverse(); } Lazy loading works for GoodChildren, but not for BadChildren. The SQL statement is correct for both children. But the wrong values are use. If the value of IMPORT_ID is 10 and the value of IMPORTSET_ID is 12. The value 10 will be used for the IMPORTSET_ID in the SQL for BadChildren instead of 12. Anyone have any ideas what I need to change to get BadChildren to work correctly? Note: GoodChildren links to IMPORT_ID on Template BadChildren links to IMPORTSET_ID on Template

    Read the article

  • where is the best palce to count the lazy load property using JPA

    - by Ke
    Let's say we have a "Question" and "Answer" entity, @Entity public class Question extends IdEntity { @Lob private String content; @Transient private int answerTotal; @OneToMany(fetch = FetchType.LAZY) private List<Answer> answers = new ArrayList<Answer>(); ...... I need to tell how many answers for the question every time Question is queryed. So I need to do count: String count = "select count(o) from Answer o WHERE o.question=:q"; My question is, where is the best place to do the count? (Because I did a lot of query about Question entity, by date, by tag, by category, by asker, etc. It is obviously not a good solution to add count operation in each query. My first attempt is to implement a @PostLoad listener, so every time Question entity is loaded, I do count. However, EntityManager cannot be injected in listener. So this way does not work. Any hint?

    Read the article

  • Lazy load images in UITableViewCell

    - by lostInTransit
    Hi I have some 50 custom cells in my UITableView. I want to display an image and a label in the cells where I get the images from URLs. I want to do a lazy load of images so the UI does not freeze up while the images are being loaded. I tried getting the images in separate threads but I have to load each image every time a cell becomes visible again (Otherwise reuse of cells shows old images) Apps like Facebook load images only for cells currently visible and once the images are loaded, they are not loaded again. Can someone please tell me how to duplicate this behavior. Thanks. Edit Trying to cache images in an NSMutableDictionary object creates problems when the user scrolls fast. I am getting images only when scrolling completely stops and clearing out the cache on memory warning. But the app invariably gets a memory warning (due to size of images being cached) and clears the cache before reloading. If scrolling is very fast, it crashes. Any other suggestions are welcome

    Read the article

  • Lazy loading Javascript, object not created from IE8 cache

    - by doum-ti-di-li-doom
    Unfortunately the bug does not happen outside of my application! Scenario index.php <?php header('Expires: Mon, 26 Jul 1997 05:00:00 GMT'); header('Last-Modified: '.gmdate('D, d M Y H:i:s').'GMT'); header('Cache-Control: no-cache, must-revalidate'); header('Pragma: no-cache'); ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" lang="en"> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8" /> <title>Lazy loader</title> </head> <body> ... <script type="text/javascript" src="internal.js"></script> ... </body> </html> internal.js myApp = { timerHitIt: false, hitIt: function () { if (arguments.callee.done) { return; } arguments.callee.done = true; if (myApp.timerHitIt) { clearInterval(myApp.timerHitIt); } var elt = document.createElement("script"); elt.async = true; elt.type = "text/javascript"; elt.src = "external.js"; elt.onload = elt.onreadystatechange = function () { alert(typeof(something)); } document.body.appendChild(elt); } } if (document.addEventListener) { document.addEventListener("DOMContentLoaded", myApp.hitIt, false); } /*@cc_on @*/ /*@if (@_win32) document.write("<script id=__ie_onload defer src="+((location.protocol == "https:") ? "//:" : "javascript:void(0)")+"><\/script>"); document.getElementById("__ie_onload").onreadystatechange = function () { if (this.readyState == "complete") { myApp.hitIt(); } }; /*@end @*/ if (/WebKit/i.test(navigator.userAgent)) { timerHitIt = setInterval(function () { if (/loaded|complete/.test(document.readyState)) { myApp.hitIt(); } }, 10); } window.onload = myApp.hitIt; external.js something = {}; alert(true); Valid results are undefined - true - object (± new request) true - object (± cached javascript) But sometimes, when hitting F5, I get true - undefined Does anyone have a clue why alert(true) is executed but something is not set?

    Read the article

  • EF4 POCO WCF Serialization problems (no lazy loading, proxy/no proxy, circular references, etc)

    - by kdawg
    OK, I want to make sure I cover my situation and everything I've tried thoroughly. I'm pretty sure what I need/want can be done, but I haven't quite found the perfect combination for success. I'm utilizing Entity Framework 4 RTM and its POCO support. I'm looking to query for an entity (Config) that contains a many-to-many relationship with another entity (App). I turn off lazy loading and disable proxy creation for the context and explicitly load the navigation property (either through .Include() or .LoadProperty()). However, when the navigation property is loaded (that is, Apps is loaded for a given Config), the App objects that were loaded already contain references to the Configs that have been brought to memory. This creates a circular reference. Now I know the DataContractSerializer that WCF uses can handle circular references, by setting the preserveObjectReferences parameter to true. I've tried this with a couple of different attribute implementations I've found online. It is needed to prevent the "the object graph contains circular references and cannot be serialized" error. However, it doesn't prevent the serialization of the entire graph, back and forth between Config and App. If I invoke it via WcfTestClient.exe, I get a stackoverflow (ha!) exception from the client and I'm hosed. I get different results from different invocation environments (C# unit test with a local reference to the web service appears to work ok though I still can drill back and forth between Configs and Apps endlessly, but calling it from a coldfusion environment only returns the first Config in the list and errors out on the others.) My main goal is to have a serialized representation of the graph I explicitly load from EF (ie: list of Configs, each with their Apps, but no App back to Config navigation.) NOTE: I've also tried using the ProxyDataContractResolver technique and keeping the proxy creation enabled from my context. This blows up complaining about unknown types encountered. I read that the ProxyDataContractResolver didn't fully work in Beta2, but should work in RTM. For some reference, here is roughly how I'm querying the data in the service: var repo = BootStrapper.AppCtx["AppMeta.ConfigRepository"] as IRepository<Config>; repo.DisableLazyLoading(); repo.DisableProxyCreation(); //var temp2 = repo.Include(cfg => cfg.Apps).Where(cfg => cfg.Environment.Equals(environment)).ToArray(); var temp2 = repo.FindAll(cfg => cfg.Environment.Equals(environment)).ToArray(); foreach (var cfg in temp2) { repo.LoadProperty(cfg, c => c.Apps); } return temp2; I think the crux of my problem is when loading up navigation properties for POCO objects from Entity Framework 4, it prepopulates navigation properties for objects already in memory. This in turn hoses up the WCF serialization, despite every effort made to properly handle circular references. I know it's a lot of information, but it's really standing in my way of going forward with EF4/POCO in our system. I've found several articles and blogs touching upon these subjects, but for the life of me, I cannot resolve this issue. Feel free to simply ask questions and help me brainstorm this situation. PS: For the sake of being thorough, I am injecting the WCF services using the HEAD build of Spring.NET for the fix to Spring.ServiceModel.Activation.ServiceHostFactory. However I don't think this is the source of the problem.

    Read the article

  • JPA2 adding referential contraint to table complicates criteria query with lazy fetch, need advice

    - by Quaternion
    Following is a lot of writing for what I feel is a pretty simple issue. Root of issue is my ignorance, not looking so much for code but advice. Table: Ininvhst (Inventory-schema inventory history) column ihtran (inventory history transfer code) using an old entity mapping I have: @Basic(optional = false) @Column(name = "IHTRAN") private String ihtran; ihtran is really a foreign key to table Intrnmst ("Inventory Transfer Master" which contains a list of "transfer codes"). This was not expressed in the database so placed a referential constraint on Ininvhst re-generating JPA2 entity classes produced: @JoinColumn(name = "IHTRAN", referencedColumnName = "TMCODE", nullable = false) @ManyToOne(optional = false) private Intrnmst intrnmst; Now previously I was using JPA2 to select the records/(Ininvhst entities) from the Ininvhst table where "ihtran" was one of a set of values. I used in.value() to do this... here is a snippet: cq = cb.createQuery(Ininvhst.class); ... In in = cb.in(transactionType); //Get in expression for transacton types for (String s : transactionTypes) { //has a value in = in.value(s);//check if the strings we are looking for exist in the transfer master } predicateList.add(in); My issue is that the Ininvhst used to contain a string called ihtran but now it contains Ininvhst... So I now need a path expression: this.predicateList = new ArrayList<Predicate>(); if (transactionTypes != null && transactionTypes.size() > 0) { //list of strings has some values Path<Intrnmst> intrnmst = root.get(Ininvhst_.intrnmst); //get transfermaster from Ininvhst Path<String> transactionType = intrnmst.get(Intrnmst_.tmcode); //get transaction types from transfer master In<String> in = cb.in(transactionType); //Get in expression for transacton types for (String s : transactionTypes) { //has a value in = in.value(s);//check if the strings we are looking for exist in the transfer master } predicateList.add(in); } Can I add ihtran back into the entity along with a join column that is both references "IHTRAN"? Or should I use a projection to somehow return Ininvhst along with the ihtran string which is now part of the Intrnmst entity. Or should I use a projection to return Ininvhst and somehow limit Intrnmst just just the ihtran string. Further information: I am using the resulting list of selected Ininvhst objects in a web application, the class which contains the list of Ininvhst objects is transformed into a json object. There are probably quite a few serialization methods that would navigate the object graph the problem is that my current fetch strategy is lazy so it hits the join entity (Intrnmst intrnmst) and there is no Entity Manager available at that point. At this point I have prevented the object from serializing the join column but now I am missing a critical piece of data. I think I've said too much but not knowing enough I don't know what you JPA experts need. What I would like is my original object to have both a string object and be able to join on the same column (ihtran) and have it as a string too, but if this isn't possible or advisable I want to hear what I should do and why. Pseudo code/English is more than fine.

    Read the article

  • how do you make a "concurrent queue safe" lazy loader (singleton manager) in objective-c

    - by Rich
    Hi, I made this class that turns any object into a singleton, but I know that it's not "concurrent queue safe." Could someone please explain to me how to do this, or better yet, show me the code. To be clear I want to know how to use this with operation queues and dispatch queues (NSOperationQueue and Grand Central Dispatch) on iOS. Thanks in advance, Rich EDIT: I had an idea for how to do it. If someone could confirm it for me I'll do it and post the code. The idea is that proxies make queues all on their own. So if I make a mutable proxy (like Apple does in key-value coding/observing) for any object that it's supposed to return, and always return the same proxy for the same object/identifier pair (using the same kind of lazy loading technique as I used to create the singletons), the proxies would automatically queue up the any messages to the singletons, and make it totally thread safe. IMHO this seems like a lot of work to do, so I don't want to do it if it's not gonna work, or if it's gonna slow my apps down to a crawl. Here's my non-thread safe code: RMSingletonCollector.h // // RMSingletonCollector.h // RMSingletonCollector // // Created by Rich Meade-Miller on 2/11/11. // Copyright 2011 Rich Meade-Miller. All rights reserved. // #import <Foundation/Foundation.h> #import "RMWeakObjectRef.h" struct RMInitializerData { // The method may take one argument. // required SEL designatedInitializer; // data to pass to the initializer or nil. id data; }; typedef struct RMInitializerData RMInitializerData; RMInitializerData RMInitializerDataMake(SEL initializer, id data); @interface NSObject (SingletonCollector) // Returns the selector and data to pass to it (if the selector takes an argument) for use when initializing the singleton. // If you override this DO NOT call super. + (RMInitializerData)designatedInitializerForIdentifier:(NSString *)identifier; @end @interface RMSingletonCollector : NSObject { } + (id)collectionObjectForType:(NSString *)className identifier:(NSString *)identifier; + (id<RMWeakObjectReference>)referenceForObjectOfType:(NSString *)className identifier:(NSString *)identifier; + (void)destroyCollection; + (void)destroyCollectionObjectForType:(NSString *)className identifier:(NSString *)identifier; @end // ==--==--==--==--==Notifications==--==--==--==--== extern NSString *const willDestroySingletonCollection; extern NSString *const willDestroySingletonCollectionObject; RMSingletonCollector.m // // RMSingletonCollector.m // RMSingletonCollector // // Created by Rich Meade-Miller on 2/11/11. // Copyright 2011 Rich Meade-Miller. All rights reserved. // #import "RMSingletonCollector.h" #import <objc/objc-runtime.h> NSString *const willDestroySingletonCollection = @"willDestroySingletonCollection"; NSString *const willDestroySingletonCollectionObject = @"willDestroySingletonCollectionObject"; RMInitializerData RMInitializerDataMake(SEL initializer, id data) { RMInitializerData newData; newData.designatedInitializer = initializer; newData.data = data; return newData; } @implementation NSObject (SingletonCollector) + (RMInitializerData)designatedInitializerForIdentifier:(NSString *)identifier { return RMInitializerDataMake(@selector(init), nil); } @end @interface RMSingletonCollector () + (NSMutableDictionary *)singletonCollection; + (void)setSingletonCollection:(NSMutableDictionary *)newSingletonCollection; @end @implementation RMSingletonCollector static NSMutableDictionary *singletonCollection = nil; + (NSMutableDictionary *)singletonCollection { if (singletonCollection != nil) { return singletonCollection; } NSMutableDictionary *collection = [[NSMutableDictionary alloc] initWithCapacity:1]; [self setSingletonCollection:collection]; [collection release]; return singletonCollection; } + (void)setSingletonCollection:(NSMutableDictionary *)newSingletonCollection { if (newSingletonCollection != singletonCollection) { [singletonCollection release]; singletonCollection = [newSingletonCollection retain]; } } + (id)collectionObjectForType:(NSString *)className identifier:(NSString *)identifier { id obj; NSString *key; if (identifier) { key = [className stringByAppendingFormat:@".%@", identifier]; } else { key = className; } if (obj = [[self singletonCollection] objectForKey:key]) { return obj; } // dynamic creation. // get a class for Class classForName = NSClassFromString(className); if (classForName) { obj = objc_msgSend(classForName, @selector(alloc)); // if the initializer takes an argument... RMInitializerData initializerData = [classForName designatedInitializerForIdentifier:identifier]; if (initializerData.data) { // pass it. obj = objc_msgSend(obj, initializerData.designatedInitializer, initializerData.data); } else { obj = objc_msgSend(obj, initializerData.designatedInitializer); } [singletonCollection setObject:obj forKey:key]; [obj release]; } else { // raise an exception if there is no class for the specified name. NSException *exception = [NSException exceptionWithName:@"com.RMDev.RMSingletonCollector.failed_to_find_class" reason:[NSString stringWithFormat:@"SingletonCollector couldn't find class for name: %@", [className description]] userInfo:nil]; [exception raise]; [exception release]; } return obj; } + (id<RMWeakObjectReference>)referenceForObjectOfType:(NSString *)className identifier:(NSString *)identifier { id obj = [self collectionObjectForType:className identifier:identifier]; RMWeakObjectRef *objectRef = [[RMWeakObjectRef alloc] initWithObject:obj identifier:identifier]; return [objectRef autorelease]; } + (void)destroyCollection { NSDictionary *userInfo = [singletonCollection copy]; [[NSNotificationCenter defaultCenter] postNotificationName:willDestroySingletonCollection object:self userInfo:userInfo]; [userInfo release]; // release the collection and set it to nil. [self setSingletonCollection:nil]; } + (void)destroyCollectionObjectForType:(NSString *)className identifier:(NSString *)identifier { NSString *key; if (identifier) { key = [className stringByAppendingFormat:@".%@", identifier]; } else { key = className; } [[NSNotificationCenter defaultCenter] postNotificationName:willDestroySingletonCollectionObject object:[singletonCollection objectForKey:key] userInfo:nil]; [singletonCollection removeObjectForKey:key]; } @end RMWeakObjectRef.h // // RMWeakObjectRef.h // RMSingletonCollector // // Created by Rich Meade-Miller on 2/12/11. // Copyright 2011 Rich Meade-Miller. All rights reserved. // // In order to offset the performance loss from always having to search the dictionary, I made a retainable, weak object reference class. #import <Foundation/Foundation.h> @protocol RMWeakObjectReference <NSObject> @property (nonatomic, assign, readonly) id objectRef; @property (nonatomic, retain, readonly) NSString *className; @property (nonatomic, retain, readonly) NSString *objectIdentifier; @end @interface RMWeakObjectRef : NSObject <RMWeakObjectReference> { id objectRef; NSString *className; NSString *objectIdentifier; } - (RMWeakObjectRef *)initWithObject:(id)object identifier:(NSString *)identifier; - (void)objectWillBeDestroyed:(NSNotification *)notification; @end RMWeakObjectRef.m // // RMWeakObjectRef.m // RMSingletonCollector // // Created by Rich Meade-Miller on 2/12/11. // Copyright 2011 Rich Meade-Miller. All rights reserved. // #import "RMWeakObjectRef.h" #import "RMSingletonCollector.h" @implementation RMWeakObjectRef @dynamic objectRef; @synthesize className, objectIdentifier; - (RMWeakObjectRef *)initWithObject:(id)object identifier:(NSString *)identifier { if (self = [super init]) { NSString *classNameForObject = NSStringFromClass([object class]); className = classNameForObject; objectIdentifier = identifier; objectRef = object; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(objectWillBeDestroyed:) name:willDestroySingletonCollectionObject object:object]; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(objectWillBeDestroyed:) name:willDestroySingletonCollection object:[RMSingletonCollector class]]; } return self; } - (id)objectRef { if (objectRef) { return objectRef; } objectRef = [RMSingletonCollector collectionObjectForType:className identifier:objectIdentifier]; return objectRef; } - (void)objectWillBeDestroyed:(NSNotification *)notification { objectRef = nil; } - (void)dealloc { [[NSNotificationCenter defaultCenter] removeObserver:self]; [className release]; [super dealloc]; } @end

    Read the article

  • Is this code well-defined?

    - by Nawaz
    This code is taken from a discussion going on here. someInstance.Fun(++k).Gun(10).Sun(k).Tun(); Is this code well-defined? Is ++k Fun() evaluated before k in Sun()? What if k is user-defined type, not built-in type? And in what ways the above function calls order is different from this: eat(++k);drink(10);sleep(k); As far as I can say, in both situations, there exists a sequence point after each function call. If so, then why can't the first case is also well-defined like the second one? Section 1.9.17 of the C++ ISO standard says this about sequence points and function evaluation: When calling a function (whether or not the function is inline), there is a sequence point after the evaluation of all function arguments (if any) which takes place before execution of any expressions or statements in the function body. There is also a sequence point after the copying of a returned value and before the execution of any expressions outside the function.

    Read the article

  • Have You Downloaded SQL Server 2012 Evaluation Edition? Why Not?!

    - by andyleonard
    I am installing SQL Server 2012 Evaluation Edition on a virtual machine as I type. You can do this. Here’s one way: Grab some virtual machine software. I like Oracle VirtualBox . It’s cool. It’s free. Install VirtualBox. Download the 180-day free trial of Windows Server 2008 R2 . Also cool. Also free. Once Windows Server 2008 R2 is downloaded, build a VirtualBox VM. Download and install SQL Server 2012 Evaluation Edition ! That’s all there is to it. You can get started today, no need to wait until...(read more)

    Read the article

  • codility challenge, test case OK , Evaluation report Wrong Answer

    - by Hussein Fawzy
    the aluminium 2014 gives me wrong answer [3 , 9 , -6 , 7 ,-3 , 9 , -6 , -10] got 25 expected 28 but when i repeated the challenge with the same code and make case test it gives me the correct answer Your test case [3, 9, -6, 7, -3, 9, -6, -10] : NO RUNTIME ERRORS (returned value: 28) what is the wrong with it ??? the challenge :- A non-empty zero-indexed array A consisting of N integers is given. A pair of integers (P, Q), such that 0 = P = Q < N, is called a slice of array A. The sum of a slice (P, Q) is the total of A[P] + A[P+1] + ... + A[Q]. The maximum sum is the maximum sum of any slice of A. For example, consider array A such that: A[0] = 3 A[1] = 2 A[2] = -6 A[3] = 3 A[4] = 1 For example (0, 1) is a slice of A that has sum A[0] + A[1] = 5. This is the maximum sum of A. You can perform a single swap operation in array A. This operation takes two indices I and J, such that 0 = I = J < N, and exchanges the values of A[I] and A[J]. To goal is to find the maximum sum you can achieve after performing a single swap. For example, after swapping elements 2 and 4, you will get the following array A: A[0] = 3 A[1] = 2 A[2] = 1 A[3] = 3 A[4] = -6 After that, (0, 3) is a slice of A that has the sum A[0] + A[1] + A[2] + A[3] = 9. This is the maximum sum of A after a single swap. Write a function: class Solution { public int solution(int[] A); } that, given a non-empty zero-indexed array A of N integers, returns the maximum sum of any slice of A after a single swap operation. For example, given: A[0] = 3 A[1] = 2 A[2] = -6 A[3] = 3 A[4] = 1 the function should return 9, as explained above. and my code is :- import java.math.*; class Solution { public int solution(int[] A) { if(A.length == 1) return A[0]; else if (A.length==2) return A[0]+A[1]; else{ int finalMaxSum = A[0]; for (int l=0 ; l<A.length ; l++){ for (int k = l+1 ; k<A.length ; k++ ){ int [] newA = A; int temp = newA[l]; newA [l] = newA[k]; newA[k]=temp; int maxSum = newA[0]; int current_max = newA[0]; for(int i = 1; i < newA.length; i++) { current_max = Math.max(A[i], current_max + newA[i]); maxSum = Math.max(maxSum, current_max); } finalMaxSum = Math.max(finalMaxSum , maxSum); } } return finalMaxSum; } } } i don't know what's the wrong with it ??

    Read the article

  • Cross-table linq query with EF4/POCO

    - by Basiclife
    Hi All, I'm new to EF(any version) and POCO. I'm trying to use POCO entities with a generic repository in a "code-first" mode(?) I've got some POCO Entities (no proxies, no lazy loading, nothing). I have a repository(of T as Entity) which provides me with basic get/getsingle/getfirst functionality which takes a lambda as a parameter (specifically a System.Func(Of T, Boolean)) Now as I'm returning the simplest possible POCO object, none of the relationship parameters work once they've been retrieved from the database (as I would expect). However, I had assumed (wrongly) that my lambda query passed to the repository would be able to use the links between entities as it would be executed against the DB before the simple POCO entities are generated. The flow is: GUI calls: Public Function GetAllTypesForCategory(ByVal CategoryID As Guid) As IEnumerable(Of ItemType) Return ItemTypeRepository.Get(Function(x) x.Category.ID = CategoryID) End Function Get is defined in Repository(of T as Entity): Public Function [Get](ByVal Query As System.Func(Of T, Boolean)) As IEnumerable(Of T) Implements Interfaces.IRepository(Of T).Get Return ObjectSet.Where(Query).ToList() End Function The code doesn't error when this method is called but does when I try to use the result set. (This seems to be a lazy loading behaviour so I tried adding the .ToList() to force eager loading - no difference) I'm using unity/IOC to wire it all up but I believe that's irrelevant to the issue I'm having NB: Relationships between entities are being configured properly and if I turn on proxies/lazy loading/etc... this all just works. I'm intentionally leaving all that turned off as some calls to the BL will be from a website but some will be via WCF - So I want the simplest possible objects. Also, I don't want a change in an object passed to the UI to be committed to the DB if another BL method calls Commit() Can someone please either point out how to make this work or explain why it's not possible? All I want to do is make sure the lambda I pass in is performed against the DB before the results are returned Many thanks. In case it matters, the container is being populated with everything as shown below: Container.AddNewExtension(Of EFRepositoryExtension)() Container.Configure(Of IEFRepositoryExtension)(). WithConnection(ConnectionString). WithContextLifetime(New HttpContextLifetimeManager(Of IObjectContext)()). ConfigureEntity(New CategoryConfig(), "Categories"). ConfigureEntity(New ItemConfig()). ... )

    Read the article

  • JSP Custom Taglib: Nested Evaluation

    - by Tiago Fernandez
    Say I have my custom taglib: <%@ taglib uri="http://foo.bar/mytaglib" prefix="mytaglib"%> <%@ taglib uri="http://java.sun.com/jstl/core" prefix="c"%> <mytaglib:doSomething> Test </mytaglib:doSomething> Inside the taglib class I need to process a template and tell the JSP to re-evaluate its output, so for example if I have this: public class MyTaglib extends SimpleTagSupport { @Override public void doTag() throws JspException, IOException { getJspContext().getOut().println("<c:out value=\"My enclosed tag\"/>"); getJspBody().invoke(null); } } The output I have is: <c:out value="My enclosed tag"/> Test When I actually need to output this: My enclosed tag Test Is this feasible? How? Thanks.

    Read the article

  • Mouse movement / mouseover and JavaScript evaluation in watir

    - by Bilal Aslam
    I have a JavaScript-heavy Rails app which I am testing in watir. I have two specific testing requirements: I need to be able to simulate moving the mouse to a specific area of the screen (or at least triggering the onmouseover event for a div) Evaluating a snippet of JavaScript once the above has happened to see if a flag is set correctly I haven't been able to figure out how to do this in watir. Any ideas on how to do this?

    Read the article

  • Boolean Expression Evaluation in Java

    - by Trilok
    Hey everyone, Is there a relatively simpler (when compared with writing a parser) way to evaluate boolean expressions in Java? I do not want to use the JEP library. I have a String expression something like: (x 4 || x < 8 && p 6) [ I will replace the variables with values. Is there a way by which I can evaluate this expression? The problem is, this can be any level deep. So, writing a parser would be really complex. Thanks

    Read the article

  • Dynamic if statement evaluation problem with string comparison

    - by Mani
    I tried the example given in this thread to create if statement dynamically using BeanShell. But it is not working fine. Instead of using "age" variable as integer, i have used string in the below example. I am getting "fail" as answer instead of "success". Can anyone help me? /* To change this template, choose Tools | Templates and open the template in the editor. */ import java.lang.reflect.*; import bsh.Interpreter; public class Main { public static String d; public static void main(String args[]) { try { String age = "30"; String cond = "age==30"; Interpreter i = new Interpreter(); i.set("age", age); System.out.println(" sss" + i.get("age")); if((Boolean)i.eval(cond)) { System.out.println("success"); } else { System.out.println("fail"); } } catch (Throwable e) { System.err.println(e); } } } Thanks, Mani

    Read the article

  • Evaluation of environment variables in command run by Java's Runtime.exec()

    - by Tom Duckering
    Hi, I have a scenarios where I have a Java "agent" that runs on a couple of platforms (specifically Windows, Solaris & AIX). I'd like to factor out the differences in filesystem structure by using environment variables in the command line I execute. As far as I can tell there is no way to get the Runtime.exec() method to resolve/evaluate any environment variables referenced in the command String (or array of Strings). I know that if push comes to shove I can write some code to pre-process the command String(s) and resolve enviroment variables by hand (using getEnv() etc). However I'm wondering if there is a smarter way to do this since I'm sure I'm not the only person wanting to do this and I'm sure there are pitfalls in "knocking up" my own implementation. Your guidance and suggestions are most welcome. edit: I would like to refer to environment variables in the command string using some consistent notation such as $VAR and/or %VAR%. Not fussed which. edit: To be clear I'd like to be able to execute a command such as: perl $SCRIPT_ROOT/somePerlScript.pl args on Windows and Unix hosts using Runtime.exec(). I specify the command in config file that describes a list of jobs to run and it has to be able to work cross platform, hence my thought that an environment variable would be useful to factor out the filesystem differences (/home/username/scripts vs C:\foo\scripts). Hope that helps clarify it. Thanks. Tom

    Read the article

  • evaluation of a java thread dump

    - by raticulin
    I got a thread dump of one of my processes. It has a bunch of these threads. I guess they are keeping a bunch of memory so I am getting OOM. "Thread-8264" prio=6 tid=0x4c94ac00 nid=0xf3c runnable [0x4fe7f000] java.lang.Thread.State: RUNNABLE at java.util.zip.Inflater.inflateBytes(Native Method) at java.util.zip.Inflater.inflate(Inflater.java:223) - locked <0x0c9bc640 (a java.util.zip.Inflater) at org.apache.commons.compress.archivers.zip.ZipArchiveInputStream.read(ZipArchiveInputStream.java:235) at com.my.ZipExtractorCommonsCompress.extract(ZipExtractorCommonsCompress.java:48) at com.my.CustomThreadedExtractorWrapper$ExtractionThread.run(CustomThreadedExtractorWrapper.java:151) Locked ownable synchronizers: - None "Thread-8241" prio=6 tid=0x4c94a400 nid=0xb8c runnable [0x4faef000] java.lang.Thread.State: RUNNABLE at java.util.zip.Inflater.inflateBytes(Native Method) at java.util.zip.Inflater.inflate(Inflater.java:223) - locked <0x0c36b808 (a java.util.zip.Inflater) at org.apache.commons.compress.archivers.zip.ZipArchiveInputStream.read(ZipArchiveInputStream.java:235) at com.my.ZipExtractorCommonsCompress.extract(ZipExtractorCommonsCompress.java:48) at com.my.CustomThreadedExtractorWrapper$ExtractionThread.run(CustomThreadedExtractorWrapper.java:151) Locked ownable synchronizers: - None I am trying to find out how it arrived to this situation. CustomThreadedExtractorWrapper is a wrapper class that fires a thread to do some work (ExtractionThread, which uses ZipExtractorCommonsCompress to extract zip contents from a compressed stream). If the task is taking too long, ExtractionThread.interrupt(); is called to cancel the operation. I can see in my logs that the cancellation happened 25 times. And I see 21 of these threads in my dump. My questions: What is the status of these threads? Alive and running? Blocked somehow? They did not die with .interrupt() apparently? Is there a sure way to really kill a thread? What does really mean 'locked ' in the stack trace? Line 223 in Inflater.java is: public synchronized int inflate(byte[] b, int off, int len) { ... //return is line 223 return inflateBytes(b, off, len); }

    Read the article

  • Lazy load pages in UIScrollView

    - by jean
    I have a UIScrollView that contains large images and am using paging to scroll between images. In order to save memory, I am loading only one image before and after the currently visible one and loading/releasing new images after a scroll has completed. The problem occurs when one scrolls quickly and scrollViewDidEndDecelerating is not called. How can I detect continuous scrolling? I could check item location on every scrollViewDidScroll but this seems a bit heavy...

    Read the article

  • Formula parsing / evaluation routine or library with generic DLookup functionality

    - by tbone
    I am writing a .Net application where I must support user-defined formulas that can perform basic mathematics, as well as accessing data from any arbitrary table in the database. I have the math part working, using JScript Eval(). What I haven't decided on is what a nice way is to do the generic table lookups. For example, I may have a formula something like: Column: BonusAmount Formula: {CurrentSalary} * 1.5 * {[SystemSettings][Value][SettingName=CorpBonus AND Year={Year}]} So, in this example I would replace {xxx} and {Year} with the value of Column xxx from the current table, and I would replace the second part with the value of (select Value from SystemSettings WHERE SettingName='CorpBonus' AND Year=2008) So, basically, I am looking for something very much like the MS Access DLookup function: DLookup ( expression, domain, [criteria] ) DLookup("[UnitPrice]", "Order Details", "OrderID = 10248") But, I also need to overall parsing routine that can tell whether to just look up in the current row, or to look into another table. Would also be nice to support aggregate functions (ie: DAvg, DMax, etc), as well as all the weird edge cases handled. So I wonder if anyone knows of any sort of an existing library, or has a nice routine that can handle this formula parsing and database lookup / aggregate function resolution requirements.

    Read the article

< Previous Page | 7 8 9 10 11 12 13 14 15 16 17 18  | Next Page >