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  • MS SQL - High performance data inserting with stored procedures

    - by Marks
    Hi. Im searching for a very high performant possibility to insert data into a MS SQL database. The data is a (relatively big) construct of objects with relations. For security reasons i want to use stored procedures instead of direct table access. Lets say i have a structure like this: Document MetaData User Device Content ContentItem[0] SubItem[0] SubItem[1] SubItem[2] ContentItem[1] ... ContentItem[2] ... Right now I think of creating one big query, doing somehting like this (Just pseudo-code): EXEC @DeviceID = CreateDevice ...; EXEC @UserID = CreateUser ...; EXEC @DocID = CreateDocument @DeviceID, @UserID, ...; EXEC @ItemID = CreateItem @DocID, ... EXEC CreateSubItem @ItemID, ... EXEC CreateSubItem @ItemID, ... EXEC CreateSubItem @ItemID, ... ... But is this the best solution for performance? If not, what would be better? Split it into more querys? Give all Data to one big stored procedure to reduce size of query? Any other performance clue? I also thought of giving multiple items to one stored procedure, but i dont think its possible to give a non static amount of items to a stored procedure. Since 'INSERT INTO A VALUES (B,C),(C,D),(E,F) is more performant than 3 single inserts i thought i could get some performance here. Thanks for any hints, Marks

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  • Design Pattern for Changing Object

    - by user210757
    Is there a Design Pattern for supporting different permutations object? Version 1 public class myOjbect { public string field1 { get; set; } /* requirements: max length 20 */ public int field2 { get; set; } . . . public decimal field200 { get; set; } } Version 2 public class myObject { public string field1 { get; set; } /* requirements: max length 40 */ public int field2 { get; set; } . . . public double field200 { get; set; } /* changed data types */ . . ./* 10 new properties */ public double field210 { get; set; } } of course I could just have separate objects, but thought there might be a good pattern for this sort of thing.

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  • An Array returned by a model association is not an Array?

    - by Warren
    We have a model association that looks something like this: class Example < ActiveRecord::Base has_many :others, :order => 'others.rank' end The rank column is an integer type. The details of these particular models are not really important though as we have found the same problem with other has_many associations between other models. We have also added to the Enumerable module: module Enumerable def method_missing(name) super unless name.to_s[0..7] == 'collect_' method = name.to_s[8..-1] collect{|element| element.send(method)} end end This adds a collect_id method that we can use to get an array of record ids from an array of ActiveRecord objects. So if we use a normal ActiveRecord find :all, we get a nice array which we can then use collect_id on but if we use Example.others.collect_id, we get NoMethodError: undefined method `collect_id' for #<Class:0x2aaaac0060a0> Example.others.class returns "Array" so is it lying or confused? Our solution thus far has been to use it this way: Example.others.to_a.collect_id This works but this seems a bit strange. Why would you have to do that? We are on Ruby 1.8.7 and Rails 2.3.4

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  • How to know the type of an object in a list?

    - by nacho4d
    Hi, I want to know the type of object (or type) I have in my list so I wrote this: void **list; //list of references list = new void * [2]; Foo foo = Foo(); const char *not_table [] = {"tf", "ft", 0 }; list[0] = &foo; list[1] = not_table; if (dynamic_cast<LogicProcessor*>(list[0])) { //ERROR here ;( printf("Foo was found\n"); } if (dynamic_cast<char*> (list[0])) { //ERROR here ;( printf("char was found\n"); } but I get : error: cannot dynamic_cast '* list' (of type 'void*') to type 'class Foo*' (source is not a pointer to class) error: cannot dynamic_cast '* list' (of type 'void*') to type 'char*' (target is not pointer or reference to class) Why is this? what I am doing wrong here? Is dynamic_cast what I should use here? Thanks in advance EDIT: I know above code is much like plain C and surely sucks from the C++ point of view but is just I have the following situation and I was trying something before really implementing it: I have two arrays of length n but both arrays will never have an object at the same index. Hence, or I have array1[i]!=NULL or array2[i]!=NULL. This is obviously a waste of memory so I thought everything would be solved if I could have both kind of objects in a single array of length n. I am looking something like Cocoa's (Objective-C) NSArray where you don't care about the type of the object to be put in. Not knowing the type of the object is not a problem since you can use other method to get the class of a certain later. Is there something like it in c++ (preferably not third party C++ libraries) ? Thanks in advance ;)

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  • fluent nhibernate - storing and retrieving three classes in/from one table

    - by Will I Am
    Noob question. I have this situation where I have these objects: class Address { string Street; string City; ... } class User { string UserID; Address BillingAddress; Address MailingAddress; ... } What is the proper way of storing this data using (fluent) nHibernate? I could use a separate Address table and create a reference, but they are 1:1 relationships so I don't really want to incur the overhead of a join. Ideally I would store this as a single flat record. So, my question is, what is the proper way of storing an instance of class 'User' in such a way that it stores its contents and also the two addresses as a single record? My knowledge is failing me on how I can store this information in such a way that the two Address records get different column names (e.g. BillingAddress_Street and MailingAddress_Street, for example), and also how to read a record back into a User instance.

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  • Python, lambda, find minimum

    - by qba
    I have foreach function which calls specified function on every element which it contains. I want to get minimum from thise elements but I have no idea how to write lambda or function or even a class that would manage that. Thanks for every help. I use my foreach function like this: o.foreach( lambda i: i.call() ) or o.foreach( I.call ) I don't like to make a lists or other objects. I want to iterate trough it and find min. I manage to write a class that do the think but there should be some better solution than that: class Min: def __init__(self,i): self.i = i def get_min(self): return self.i def set_val(self,o): if o.val < self.i: self.i = o.val m = Min( xmin ) self.foreach( m.set_val ) xmin = m.get_min() Ok, so I suppose that my .foreach method is non-python idea. I should do my Class iterable because all your solutions are based on lists and then everything will become easier. In C# there would be no problem with lambda function like that, so I though that python is also that powerful.

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  • Framework/service for hosting and managing files

    - by Peteris Caune
    Hi, in a webapp I'm building there is a planned side feature of supporting product illustrations and manuals (so pictures and PDFs), possibly arranged in galleries. As I'd rather not implement from scratch all of the uploading, managing and serving of this content, I'm looking for existing solutions which I could integrate. For example, I'm considering Flickr--users of webapp specify their Flickr username and then use some naming convention to link objects in my webapp with pictures uploaded in their Flickr account. Very little code to write from my side, maybe just some API calls that proxy Flickr APIs, since Flickr would handle picture uploading, organizing them in sets, storing them in cloud and serving them in various sizes etc. One drawback here is that either all of the the pictures are public or I have to deal with interactive Flickr authorization. Also not sure if Flickr would be happy being used in such manner. What other online services or libraries/frameworks I should look at? My webapp is written in Python/Pylons, so Python libraries would be preferred. I'm already using some of Amazon infrastructure, so frontends to Amazon S3 would be cool. For online services, RESTful API would be nice.

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  • Calling an Overridden Method from a Parent-Class Constructor

    - by Vaibhav Bajpai
    I tried calling an overridden method from a constructor of a parent class and noticed different behavior across languages. C++ - echoes A.foo() class A{ public: A(){foo();} virtual void foo(){cout<<"A.foo()";} }; class B : public A{ public: B(){} void foo(){cout<<"B.foo()";} }; int main(){ B *b = new B(); } Java - echoes B.foo() class A{ public A(){foo();} public void foo(){System.out.println("A.foo()");} } class B extends A{ public void foo(){System.out.println("B.foo()");} } class Demo{ public static void main(String args[]){ B b = new B(); } } C# - echoes B.foo() class A{ public A(){foo();} public virtual void foo(){Console.WriteLine("A.foo()");} } class B : A{ public override void foo(){Console.WriteLine("B.foo()");} } class MainClass { public static void Main (string[] args) { B b = new B(); } } I realize that in C++ objects are created from top-most parent going down the hierarchy, so when the constructor calls the overridden method, B does not even exist, so it calls the A' version of the method. However, I am not sure why I am getting different behavior in Java and C#.

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  • Creation of model in core data on the fly

    - by user1740045
    How can we create a model in core data on the fly? I.e getting the schema of database from somewhere and then creating a Core Data Object graph? *QuesTion:* Yes thats fine, agreed with all the advantages. But, can anybody can tell practically, what is the benefit of integrating Core Data into project instead of using SQL directly. 1.No need to write SQL boiler plate code [but need to learn Core Data Model (steep curve)] 2.WE can undo and redo changes [but practically who needs it] 3.we can migrate to another schema [that can be done by SQLite as well jus need to add another field into table] 4.For say aggregation on some field in table,in Core Data we need to loop through Core Data Objects whereas in SQLite we need to first write SQLite Boiler Plate Code and then the basic aggregation SQL query,which is easy to write,only length of code will increase...But in case of Core Data (need to learn a lot). So apart from reducing the length of Code,does it actually adds value to project? or in terms of Memory Efficiency,Performance,etc.. PS: If anybody has actualy worked on Core Data(Model Creation On the Fly) , if possible share and gve pointers..thanks!

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  • What happens when you create an instance of an object containing no state in C#?

    - by liquorice
    I am I think ok at algorithmic programming, if that is the right term? I used to play with turbo pascal and 8086 assembly language back in the 1980s as a hobby. But only very small projects and I haven't really done any programming in the 20ish years since then. So I am struggling for understanding like a drowning swimmer. So maybe this is a very niave question or I'm just making no sense at all, but say I have an object kind of like this: class Something : IDoer { void Do(ISomethingElse x) { x.DoWhatEverYouWant(42); } } And then I do var Thing1 = new Something(); var Thing2 = new Something(); Thing1.Do(blah); Thing2.Do(blah); does Thing1 = Thing2? does "new Something()" create anything? Or is it not much different different from having a static class, except I can pass it around and swap it out etc. Is the "Do" procedure in the same location in memory for both the Thing1(blah) and Thing2(blah) objects? I mean when executing it, does it mean there are two Something.Do procedures or just one?

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  • Applying a function that may fail to all values in a list

    - by Egwor
    I want to apply a function f to a list of values, however function f might randomly fail (it is in effect making a call out to a service in the cloud). I thought I'd want to use something like map, but I want to apply the function to all elements in the list and afterwards, I want to know which ones failed and which were successful. Currently I am wrapping the response objects of the function f with an error pair which I could then effectively unzip afterwards i.e. something like g : (a->b) -> a -> [ b, errorBoolean] f : a-> b and then to run the code ... map g (xs) Is there a better way to do this? The other alternative approach was to iterate over the values in the array and then return a pair of arrays, one which listed the successful values and one which listed the failures. To me, this seems to be something that ought to be fairly common. Alternatively I could return some special value. What's the best practice in dealing with this??

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  • Accessing Application Scoped Bean Causes NullPointerException

    - by user2946861
    What is an Application Scoped Bean? I understand it to be a bean which will exist for the life of the application, but that doesn't appear to be the correct interpretation. I have an application which creates an application scoped bean on startup (eager=true) and then a session bean that tries to access the application scoped bean's objects (which are also application scoped). But when I try to access the application scoped bean from the session scoped bean, I get a null pointer exception. Here's excerpts from my code: Application Scoped Bean: @ManagedBean(eager=true) @ApplicationScoped public class Bean1 implements Serializable{ private static final long serialVersionUID = 12345L; protected ArrayList<App> apps; // construct apps so they are available for the session scoped bean // do time consuming stuff... // getters + setters Session Scoped Bean: @ManagedBean @SessionScoped public class Bean2 implements Serializable{ private static final long serialVersionUID = 123L; @Inject private Bean1 bean1; private ArrayList<App> apps = bean1.getApps(); // null pointer exception What appears to be happening is, Bean1 is created, does it's stuff, then is destroyed before Bean2 can access it. I was hoping using application scoped would keep Bean1 around until the container was shutdown, or the application was killed, but this doesn't appear to be the case.

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  • Determining an object's variable name dynamically?

    - by ZenBlender
    Let's say I have some objects: ArrayList<SomeObject> list = new ArrayList<SomeObject>(); SomeObject A = new SomeObject(); SomeObject B = new SomeObject(); SomeObject C = new SomeObject(); SomeObject D = new SomeObject(); These constructors automatically add each object to the ArrayList so I can iterate over them but still maintain the variable names for direct access: public SomeObject(){ // init stuff here list.add(this); } But then, let's say I want to output some debug info, and iterate through list and print out the NAME of each object? How can I do that? Essentially, when "SomeObject A = new SomeObject();" is executed, I want to use reflection (if possible) to determine that this variable's name is "A" (a String) and either store that in the object when the constructor executes, or determine it dynamically through reflection when referencing this object with the variable named "A". Does that make sense? How can I do this? Thanks!

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  • Processing data from an AJAX request

    - by Josh K
    I have a PHP API I'm working with that outputs everything as JSON. I need to call one of the API methods and parse it out using an AJAX request. I am using jQuery (though it shouldn't matter). When I make the request it errors out with a "parsererror" as the textStatus and a "Syntax Error: invalid label" when I make the request. Simplified code: $.ajax ({ type: "POST", url: "http://mydomain.com/api/get/userlist/"+mid, dataType: "json", dataFilter: function(data, type) { /* Here we assume and pray */ users = eval(data); alert(users[1].id); }, success: function(data, textStatus, XMLHttpRequest) { alert(data.length); // Should be an array, yet is undefined. }, error: function(XMLHttpRequest, textStatus, errorThrown) { alert(textStatus); alert(errorThrown); }, complete: function(XMLHttpRequest, textStatus) { alert("Done"); } }); If I leave off the eval(data) then everything works fine. Well, except for data still being undefined in success. Note that I'm taking an array of objects in PHP and then passing them out through json_encode. Would that make any difference? There has been no progress made on this. I'm willing to throw more code up if someone believes they can help. Here is the PHP side of things private function _get_user_colors($id) { $u = new User(); $u->get_where(array('id' => $id)); $bar = array(); $bar['user'] = $u->stored; foreach($user->colors as $color) { $bar['colors'][] = $color; } echo(json_encode($bar)); } I have had zero issues using this with other PHP based scripts. I don't know why Javascript would take issue with it.

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  • JPA 2.0 Provider Hibernate Spring MVC 3.0

    - by user558019
    Dear All i have very strange problem we are using jpa 2.0 with hibernate and spring 3.0 mvc annotations based Database generated through JPA DDL is true and MySQL as Database; i will provide some refference classes and then my porblem. public abstract class Common implements serializable{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "id", updatable = false) private Long id; @ManyToOne @JoinColumn private Address address; //with all getter and setters //as well equal and hashCode } public class Parent extends Common{ private String name; @OneToMany(cascade = {CascadeType.MERGE,CascadeType.PERSIST}, mappedBy = "parent") private List<Child> child; //setters and rest of class } public class child extends Common{ //some properties with getter/setters } public class Address implements Serializable{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "id", updatable = false) private Long id; private String street; //rest of class with get/setter } as in code you can see that parents and child classes extends Common class so both have address property and id , the problem occurs when change the address refference in parent class it reflect same change in all child objects in list and if change address refference in child class then on merge it will change address refference of parent as well i am not able to figure out is it is problem of jpa or hibernate or spring thanks in advance

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  • Overhead of calling tiny functions from a tight inner loop? [C++]

    - by John
    Say you see a loop like this one: for(int i=0; i<thing.getParent().getObjectModel().getElements(SOME_TYPE).count(); ++i) { thing.getData().insert( thing.GetData().Count(), thing.getParent().getObjectModel().getElements(SOME_TYPE)[i].getName() ); } if this was Java I'd probably not think twice. But in performance-critical sections of C++, it makes me want to tinker with it... however I don't know if the compiler is smart enough to make it futile. This is a made up example but all it's doing is inserting strings into a container. Please don't assume any of these are STL types, think in general terms about the following: Is having a messy condition in the for loop going to get evaluated each time, or only once? If those get methods are simply returning references to member variables on the objects, will they be inlined away? Would you expect custom [] operators to get optimized at all? In other words is it worth the time (in performance only, not readability) to convert it to something like: ElementContainer &source = thing.getParent().getObjectModel().getElements(SOME_TYPE); int num = source.count(); Store &destination = thing.getData(); for(int i=0;i<num;++i) { destination.insert(thing.GetData().Count(), source[i].getName(); } Remember, this is a tight loop, called millions of times a second. What I wonder is if all this will shave a couple of cycles per loop or something more substantial? Yes I know the quote about "premature optimisation". And I know that profiling is important. But this is a more general question about modern compilers, Visual Studio in particular.

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  • Best practice when removing entity regarding mappedBy collections?

    - by Daniel Bleisteiner
    I'm still kind of undecided which is the best practice to handle em.remove(entity) with this entity being in several collections mapped using mappedBy in JPA. Consider an entity like a Property that references three other entities: a Descriptor, a BusinessObject and a Level entity. The mapping is defined using @ManyToOne in the Property entity and using @OneToMany(mappedBy...) in the other three objects. That inverse mapping is defined because there are some situations where I need to access those collections. Whenever I remove a Property using em.remove(prop) this element is not automatically removed from managed entities of the other three types. If I don't care about that and the following page load (webapp) doesn't reload those entities the Property is still found and some decisions might be taken that are no longer true. The inverse mappings may become quite large and though I don't want to use something like descriptor.getProperties().remove(prop) because it will load all those properties that might have been lazy loaded until then. So my currently preferred way is to refresh the entity if it is managed: if (em.contains(descriptor)) em.refresh(descriptor) - which unloads a possibly loaded collection and triggers a reload upon the next access. Is there another feasible way to handle all those mappedBy collections of already loaded entites?

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  • iPad search bar bad memory access?

    - by Geoff Baum
    Hello all, So I am trying to implement a search bar in my app and am very close but can't seem to figure out where this memory error is occurring. This is what part of my search method looks like: filters = [[NSMutableArray alloc] init]; NSString *searchText = detailSearch.text; NSMutableArray *searchArray = [[NSMutableArray alloc] init]; // Normally holds the object (ex: 70 locations) searchArray = self.copyOfFilters ; //This is the line that is breaking after ~2-3 letters are entered in the search for (NSString *sTemp in searchArray) { NSRange titleResultsRange = [sTemp rangeOfString:searchText options:NSCaseInsensitiveSearch]; if (titleResultsRange.length > 0) [filters addObject:sTemp]; } displayedFilters = filters; copyOfFilters is a deep copy of the displayed filters that appear when the view first loads via: self.copyOfFilters = [[NSMutableArray alloc] initWithArray:displayedFilters copyItems:YES]; I have traced through the entry of letters and it is accurate after 2 letters, but once you try and enter a letter after a space in the search bar, it crashes. The value of copyOfFilters = {(int)[$VAR count]} objects. Does anyone know what may be causing this? Thanks!

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  • No result when Rally.data.WsapiDataStore lacks permissions

    - by user1195996
    I'm calling Ext.create('Rally.data.WsapiDataStore', params), and looking for results with the load event. I'm requesting a number of objects across programs that the user may or may not have read permission for. This works fine for queries where the user has permissions. But in the case where the user does not have permission and presumably gets zero results back, the load event does not seem to fire at all. I would expect it to fire with the unsuccessful flag or else to return with empty results. Since I don't know that the request has failed, my program waits and waits. How can I tell if a this request fails to return because of security? BTW, looking at the network stats, I believe all my requests get a "200 OK" status back. Here is the method I use to create the various data stores: _createDataStore: function(params) { this.openRequests++; var createParams = { model: params.type, autoLoad: true, // So I can later determine which query type it is, and which program requestType: params.requestType == undefined ? params.type : params.requestType, program: this.program, listeners: { load: this._onDataLoaded, scope: this }, filters: params.filters, pageSize: params.pageSize, fetch: params.fetch, context: { project: this.project, projectScopeUp: false, projectScopeDown: true }, pageSize: 1 // We only need the count }; console.log('_createDataStore', this.program, createParams.requestType); Ext.create('Rally.data.WsapiDataStore', createParams); }, And here is the _onDataLoaded method: _onDataLoaded: function(store, data, successB) { console.log('_onDataLoaded', this.program, successB); ... I only see this function called for those queries for which the account has permissions.

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  • What to throw in a C++ class wrapping a C library ?

    - by ereOn
    I have to create a set of wrapping C++ classes around an existing C library. For many objects of the C library, the construction is done by calling something like britney_spears* create_britney_spears() and the opposite function void free_britney_spears(britney_spears* brit). If the allocation of a britney_spears fails, create_britney_spears() returns NULL. This is, as far as I know, a very common pattern. Now I want to wrap this inside a C++ class. //britney_spears.hpp class BritneySpears { public: BritneySpears(); private: boost::shared_ptr<britney_spears> m_britney_spears; }; And here is the implementation: // britney_spears.cpp BritneySpears::BritneySpears() : m_britney_spears(create_britney_spears(), free_britney_spears) { if (!m_britney_spears) { // Here I should throw something to abort the construction, but what ??! } } So the question is in the code sample: What should I throw to abort the constructor ? I know I can throw almost anything, but I want to know what is usually done. I have no other information about why the allocation failed. Should I create my own exception class ? Is there a std exception for such cases ? Many thanks.

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  • CArray doesn't call copy constructors on memory reallocations, now what?

    - by MMx
    Suppose I have a class that requires copy constructor to be called to make a correct copy of: struct CWeird { CWeird() { number = 47; target = &number; } CWeird(const CWeird &other) : number(other.number), target(&number) { } void output() { printf("%d %d\n", *target, number); } int *target, number; }; Now the trouble is that CArray doesn't call copy constructors on its elements when reallocating memory (only memcpy from the old memory to the new), e.g. this code CArray<CWeird> a; a.SetSize(1); a[0].output(); a.SetSize(2); a[0].output(); results in 47 47 -572662307 47 I don't get this. Why is it that std::vector can copy the same objects properly and CArray can't? What's the lesson here? Should I use only classes that don't require explicit copy constructors? Or is it a bad idea to use CArray for anything serious?

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  • Which Java debugger do *you* use.

    - by mikevdg
    I spend a lot of time debugging applications in Eclipse using JPDA. There are a few issues with the Eclipse debugger which really annoy me. Can anybody recommend plug-ins, better debuggers or perhaps tricks that I don't know of yet? In the "Variables" tab, you can type in and execute bits of Java code. However, you first need to click on something (I usually click on "this") to give it some context. Then, after you've typed in a lengthy Java expression to debug something and "execute" it, your expression gets replaced with the result, so you need to type it in all over again. Is there some better way, such as a console or something that I'm missing? When you're poking through data structures, the presentation in the debugger leaves much to be desired. You see the internal representation of Lists, Maps, StringBuilders etc. What I want to see is what these objects conceptually contain. Is there a way of doing this, perhaps using some other debugger, or an extension or something? When an Exception is thrown, is there some way of inspecting the state of the application where the Exception was thrown? Currently I need to set breakpoints just before the Exception occurs and then try to reproduce it. When I'm stepping over a line with many statements on it, I can't actually see which of those statements is being executed, except by "stepping in" to each one to see where it takes me. If no source code is found, Eclipse just stares blankly at you. You get a helpful screen saying "Class File Editor / Source code not found" which is completely useless. I'd much prefer to be able to step through the bytecodes so I can at least see what is going on. Does anybody know of a Java debugger that does this better than Eclipse?

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  • What's a good way to format AJAX responses? Or, using Django templating with AJAX

    - by synic
    In some of the code I'm working on, the author max AJAX calls to a Django view that returns JSON. Once the JSON is retrieved, it'll be injected into the page with a function that looks like this (note, this is a simplification, but I'm sure you know what I'm getting at here): function build_event_listing(events) { var html = ''; for(int i = 0; i < events.length; i++) { event = events[i]; html += "<h2>" + event.title + "</h2>\n"; html += "<p>" + event.description + "</p>"; html += "Click <a href='/event/view/" + event.id + "'>here<a> for more info."; } events_div.html(html); } I really don't like this approach. To change the look of each event listing, the designer would have to modify that ugly JS. I'd much rather make use of Django's templating system, but I'm wondering how I can do this? I had the idea of writing the view like this: def view_listings(req): events = models.Event.objects.all() html = [] for event in events: html.append( render_to_string('event/single_event.html', { 'event': event, }, context_instance=RequestContext(req)) return HttpResponse(''.join(html), mimetype='text/html') ... but it just seems like there should be a better way. Any ideas?

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  • Question about singleton property

    - by Jack
    I'm reading the java tutorial for enums located here and have a question: http://java.sun.com/j2se/1.5.0/docs/guide/language/enums.html#Card The part i'm confused about is as follows: "The Card class, above, contains a static factory that returns a deck, but there is no way to get an individual card from its rank and suit. Merely exposing the constructor would destroy the singleton property (that only a single instance of each card is allowed to exist). Here is how to write a static factory that preserves the singleton property, using a nested EnumMap: " Now as I understand, changing the original private "Card" constructor to public would allow us to instantiate an unlimited number of copies of a "Card" object with a given suit+rank. The solution as proposed was to create an EnumMap which would store four Maps (one for each suit), which themselves contained 13 Card objects with the rank as their keys. And so now if you wanted to retrieve a specific Card object from the deck, you would just call the "valueOf" method. My question now is, what's the prevent you with calling the valueOf method as many times as you like? Wouldn't that lead to the same problem as making the original private constructor public? Thanks.

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  • AS3 colorTransform over multiple frames?

    - by user359519
    (Flash Professional, AS3) I'm working on a custom avatar system where you can select various festures and colors. For example, I have 10 hairstyles, and a colorPicker to change the color. mc_myAvatar has 10 frames. Each frame has a movieclip of a different hairstyle (HairStyle1, HairStyle2, etc.) Here's my code: var hairColor:ColorTransform; hairColor = mc_myAvatar.hair.colorLayer.transform.colorTransform; hairColor.color = 0xCCCC00; mc_myAvatar.hair.colorLayer.transform.colorTransform = hairColor; This correctly changes the initial color. I have a "nextHair" button to advance mc_myAvatar.hair to the next frame. When I click the button, I get an error message saying that I have a null object reference. I added a trace, and mc_myAvatar.hair.colorLayer is null on frame 2. Why??? I've clearly named HairStyle2 as "colorLayer" in frame 2. I think the problem is related to me using the same name for different classes/movieclips, but I don't know how to fix the problem... I added a square movieclip below my hairStyle movieclips, named the square "colorLevel", and deleted the name from my hairStyle clips. When I click the next button, the square correctly maintains the color from frame to frame. However, having a square doesn't do me much good. :( I tried converting the hairStyle layer to a mask. Doing this, however, results in yet another "null object" error - mc_myAvatar.hair.colorLayer is null after frame 1. I even tried "spanning" my colorLevel across all frames (no keyframes), thinking that this would give me just one movieclip to work with. No luck. Same error! What's going on, here? Why am I getting these null objects, when they are clearly defined in my movieclip? I'm also open to suggestions on a better way to do multiple frames and colors.

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