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  • Getting the ID of an object when the object is given

    - by Pieter
    I have link that calls a function when clicked: <a href="javascript:spawnMenu(this);" id="link1">Test1</a> To make my function work, I need access to the object so that I can perform jQuery operations like this: alert($(objCaller).offset().left); Since objCaller points to the object and not the object ID, this won't work. I need something like this: alert($("a#link1").offset().left); How can I get the object ID from objCaller?

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  • Class instance clustering in object reference graph for multi-entries serialization

    - by Juh_
    My question is on the best way to cluster a graph of class instances (i.e. objects, the graph nodes) linked by object references (the -directed- edges of the graph) around specifically marked objects. To explain better my question, let me explain my motivation: I currently use a moderately complex system to serialize the data used in my projects: "marked" objects have a specific attributes which stores a "saving entry": the path to an associated file on disc (but it could be done for any storage type providing the suitable interface) Those object can then be serialized automatically (eg: obj.save()) The serialization of a marked object 'a' contains implicitly all objects 'b' for which 'a' has a reference to, directly s.t: a.b = b, or indirectly s.t.: a.c.b = b for some object 'c' This is very simple and basically define specific storage entries to specific objects. I have then "container" type objects that: can be serialized similarly (in fact their are or can-be "marked") they don't serialize in their storage entries the "marked" objects (with direct reference): if a and a.b are both marked, a.save() calls b.save() and stores a.b = storage_entry(b) So, if I serialize 'a', it will serialize automatically all objects that can be reached from 'a' through the object reference graph, possibly in multiples entries. That is what I want, and is usually provides the functionalities I need. However, it is very ad-hoc and there are some structural limitations to this approach: the multi-entry saving can only works through direct connections in "container" objects, and there are situations with undefined behavior such as if two "marked" objects 'a'and 'b' both have a reference to an unmarked object 'c'. In this case my system will stores 'c' in both 'a' and 'b' making an implicit copy which not only double the storage size, but also change the object reference graph after re-loading. I am thinking of generalizing the process. Apart for the practical questions on implementation (I am coding in python, and use Pickle to serialize my objects), there is a general question on the way to attach (cluster) unmarked objects to marked ones. So, my questions are: What are the important issues that should be considered? Basically why not just use any graph parsing algorithm with the "attach to last marked node" behavior. Is there any work done on this problem, practical or theoretical, that I should be aware of? Note: I added the tag graph-database because I think the answer might come from that fields, even if the question is not.

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  • Is MVC a Design Pattern or Architectural pattern

    - by JCasso
    According to Sun and Msdn it is a design pattern. According to Wikipedia it is an architectural pattern In comparison to design patterns, architectural patterns are larger in scale. (Wikipedia - Architectural pattern) Or it is an architectural pattern that also has a design pattern ? Which one is true ?

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  • Output a NULL cell value in Excel

    - by Peter
    I have an IF statement. If a cell = n, then do something, else output NULL =IF(A1=5, "Success", NULL) // #NAME? =IF(A1=5, "Success", "NULL") // NULL (as in text, not actually NULL!) =IF(A1=5, "Success", "") // blank but not NULL =IF(A1=5, "Success", 0) // zero value but not NULL

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  • Design for object with optional and modifiable attributtes?

    - by Ikuzen
    I've been using the Builder pattern to create objects with a large number of attributes, where most of them are optional. But up until now, I've defined them as final, as recommended by Joshua Block and other authors, and haven't needed to change their values. I am wondering what should I do though if I need a class with a substantial number of optional but non-final (mutable) attributes? My Builder pattern code looks like this: public class Example { //All possible parameters (optional or not) private final int param1; private final int param2; //Builder class public static class Builder { private final int param1; //Required parameters private int param2 = 0; //Optional parameters - initialized to default //Builder constructor public Builder (int param1) { this.param1 = param1; } //Setter-like methods for optional parameters public Builder param2(int value) { param2 = value; return this; } //build() method public Example build() { return new Example(this); } } //Private constructor private Example(Builder builder) { param1 = builder.param1; param2 = builder.param2; } } Can I just remove the final keyword from the declaration to be able to access the attributes externally (through normal setters, for example)? Or is there a creational pattern that allows optional but non-final attributes that would be better suited in this case?

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  • parse [object XrayWrapper [object HTMLLIElement]] into HTML object

    - by kitokid
    when I access and GM_log the currentLi of li object, it is complaining undefined. So when I GM_log li value as a string , instead of HTML object, I am getting [object XrayWrapper [object HTMLLIElement]]. How can I convert it or how I can access its related elements and value ? $("#result-set li").each(function(index) { var $currentLi = $(this); var $class1link = $currentLi.find("class1"); var $class1href = $class1link.attr("href"); }

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  • null != null - any ideas on how to re-arrange the code or prevent this?

    - by Alex
    Currently debugging, and found an if-statement which for no (I thought...) reason gave me an NPE, obviously for a reason. Which seemed to be that the statement turned out to be if(false && (null != null || null != Color)). if(destination != null && (destination.getPiece() != null || destination.getPiece().getColour() != pieceColour)) - the if-statement Both destination can be null and piece can be. The getColour() method returns an attribute of type Color from piece, which must be null if the piece is null. The piece at destination has a different pieceColour attribute then the one in the if-statement. Specifically, how do I re-arrange (destination.getPiece() != null) ?

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  • Problem evaluating NULL in an IIF statement (Access)

    - by Mohgeroth
    Item in the recordset rstImportData("Flat Size") is = Null With that, given the following statement: IIF(IsNull(rstImportData("Flat Size")), Null, cstr(rstImportData("Flat Size"))) Result: Throws error 94: Invalid use of Null If I change the statement by removing the type conversion upon a false comparison: IIF(IsNull(rstImportData("Flat Size")), Null, 0) Result: Null It returns Null as it should have the first time. It appears that I cannot do a type conversion in an IIF if the value passed in should ever be null even if it passes an IIF test, it still attempts to evaluate it at both the true and false answer. The only reason I'm using IIF like this is because I have a 25 line comparison to compare data from an Import against a matching record in a database to see if I need to append the prior to history. Any thoughts? The way data is imported there will be null dates and where the spreadsheet import is in a string format I must convert either side to the other to compare the values properly but if either side is null this exception occurs :(

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  • Multiple Object Instantiation

    - by Ricky Baby
    I am trying to get my head around object oriented programming as it pertains to web development (more specifically PHP). I understand inheritance and abstraction etc, and know all the "buzz-words" like encapsulation and single purpose and why I should be doing all this. But my knowledge is falling short with actually creating objects that relate to the data I have in my database, creating a single object that a representative of a single entity makes sense, but what are the best practises when creating 100, 1,000 or 10,000 objects of the same type. for instance, when trying to display a list of the items, ideally I would like to be consistent with the objects I use, but where exactly should I run the query/get the data to populate the object(s) as running 10,000 queries seems wasteful. As an example, say I have a database of cats, and I want a list of all black cats, do I need to set up a FactoryObject which grabs the data needed for each cat from my database, then passes that data into each individual CatObject and returns the results in a array/object - or should I pass each CatObject it's identifier and let it populate itself in a separate query.

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  • Help to understand the abstract factory pattern

    - by Chobeat
    I'm learning the 23 design patterns of the GoF. I think I've found a way to understand and simplify how the Abstract Factory works but I would like to know if this is a correct assumption or if I am wrong. What I want to know is if we can see the result of the Abstract Factory method as a matrix of possible products where there's a Product for every "Concrete Factory" x "AbstractProduct" where the Concrete Factory is a single implementation among the implementations of an AbstractFactory and an AbstractProduct is an interface among the interfaces to create Products. Is this correct or am I missing something?

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  • Design pattern and best practices

    - by insane-36
    I am an iphone developer. I am quite confident on developing iphone application with some minimal feature. I would consider myself as a fair application developer but the code I write is not so much structured. I make vey little use of MVC because I dont seem to find places to impose MVC. Most of the time, I create application with viewcontrollers and very few models only. How could I improve the skill for making my code more reusable, standard, easy and maintainable. I have seen few books on design patterns and tried few chapters myself but I dont seem to skip my habit. I know few of them but I am not being able to apply those patterns into my app. What is the best way to learn the design patterns and coding habit. Any kind of suggestion is warmly welcomed.

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  • Is ORM an Anti-Pattern?

    - by derphil
    I had a very stimulating and interessting discussion with a colleague about ORM and it's Pros and Cons. In my opinion, an ORM is useful only in the rarest cases. At least in my experience. But I don't want to list my own arguments at this time. So I ask you, what do you think about ORM? What are the Pros and the Cons? P.S. I've posted this "question" yesterday on Stackoverflow, but some of the user think, that this should better posted here.

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  • good literature for teaching object oriented thinking in C [closed]

    - by Dipan Mehta
    Quite often C is the primary platform for the development. And when things are large scale, I have seen partitioning of the system as different objects is quite a natural thing. Some or many of the object orientated analysis and design principles are used here very well. This is not a debate question about whether or not C is a good candidate for object oriented programming or not. This is also NOT a question how to do OO in C. You can refer to this question and there are probably many such citations. As far as I am concerned, I have learned some of this things while working with many open source and commercial projects. (libjpeg, ffmpeg, Gstreamer which is based on GObject). I can probably extend a few references that explains some of these concepts such as - 1. Event Helix article, 2. Linux Mag article 3. one of my answers which links Schreiner's reference. Unfortunately, when we induct younger folks, it seems too hard to make them learn all of it the hard way. Usually, when we say it's C, a general reaction is to throw away all of the "Object thinking". Looking for help extending above references from those who have been in the similar areas of work. Are there any good formal literature that explains how Object thinking can be made to use while you are working in C? I have seen tons of book on general "object oriented paradigms" but they all focus on advanced languages mostly not in C. You see most C books - but most focus only on the syntax and the obfuscated corners of C and that's it. There are hardly ANY good reference, specially books or any systematic (I mean formal) literature on how to apply OO in C. This is very surprising given that so many large scale open source projects use C which are truly using this very well; but we hardly see any good formal literature on this subject.

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  • Console.log in IE on an object just outputted [object Object]

    - by LookitsPuck
    All, I'm used to debugging JavaScript in Chrome or Firefox just because their built in developer tools are a lot cleaner than IE's. IE8 came along way with the Developer Tools being more polished, but they're still not completely up to snuff. I like being able to step through code as if I was in Visual Studio, and that is pretty nice about IE, however, when trying to do a simple console.log on an object that I have, in Firefox/Chrome/etc. I can actually explore that object. In IE, the console is simply outputting the following: LOG: [object Object] Is there any way to drill down into that object in IE like in Chrome/Firefox/etc.? Thanks all! -Steve

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  • AntFarm anti-pattern -- strategies to avoid, antidotes to help heal from

    - by alchemical
    I'm working on a 10 page web site with a database back-end. There are 500+ objects in use, trying to implement the MVP pattern in ASP.Net. I'm tracing the code-execution from a single-page, my finger has been on F-11 in Visual Studio for about 40 minutes, there seems to be no end, possibly 1000+ method calls for one web page! If it was just 50 objects that would be one thing, however, code execution snakes through all these objects just like millions of ants frantically woring in their giant dirt mound house, riddled with object tunnels. Hence, a new anti-pattern is born : AntFarm. AntFarm is also known as "OO-Madnes", "OO-Fever", OO-ADD, or simply design-pattern junkie. This is not the first time I've seen this, nor my associates at other companies. It seems that this style is being actively propogated, or in any case is a misunderstanding of the numerous OO/DP gospels going around... I'd like to introduce an anti-pattern to the anti-pattern: GST or "Get Stuff Done" AKA "Get Sh** done" AKA GRD (GetRDone). This pattern focused on just what it says, getting stuff done, in a simple way. I may try to outline it more in a later post, or please share your ideas on this antidote pattern. Anyway, I'm in the midst of a great example of AntFarm anti-pattern as I write (as a bonus, there is no documentation or comments). Please share you thoughts on how this anti-pattern has become so prevelant, how we can avoid it, and how can one undo or deal with this pattern in a live system one must work with!

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  • Merging .net object graph

    - by Tiju John
    Hi guys, has anyone come across any scenario wherein you needed to merge one object with another object of same type, merging the complete object graph. for e.g. If i have a person object and one person object is having first name and other the last name, some way to merge both the objects into a single object. public class Person { public Int32 Id { get; set; } public string FirstName { get; set; } public string LastName { get; set; } } public class MyClass { //both instances refer to the same person, probably coming from different sources Person obj1 = new Person(); obj1.Id=1; obj1.FirstName = "Tiju"; Person obj2 = new Person(); ojb2.Id=1; obj2.LastName = "John"; //some way of merging both the object obj1.MergeObject(obj2); //?? //obj1.Id // = 1 //obj1.FirstName // = "Tiju" //obj1.LastName // = "John" } I had come across such type of requirement and I wrote an extension method to do the same. public static class ExtensionMethods { private const string Key = "Id"; public static IList MergeList(this IList source, IList target) { Dictionary itemData = new Dictionary(); //fill the dictionary for existing list string temp = null; foreach (object item in source) { temp = GetKeyOfRecord(item); if (!String.IsNullOrEmpty(temp)) itemData[temp] = item; } //if the same id exists, merge the object, otherwise add to the existing list. foreach (object item in target) { temp = GetKeyOfRecord(item); if (!String.IsNullOrEmpty(temp) && itemData.ContainsKey(temp)) itemData[temp].MergeObject(item); else source.Add(item); } return source; } private static string GetKeyOfRecord(object o) { string keyValue = null; Type pointType = o.GetType(); if (pointType != null) foreach (PropertyInfo propertyItem in pointType.GetProperties()) { if (propertyItem.Name == Key) { keyValue = (string)propertyItem.GetValue(o, null); } } return keyValue; } public static object MergeObject(this object source, object target) { if (source != null && target != null) { Type typeSource = source.GetType(); Type typeTarget = target.GetType(); //if both types are same, try to merge if (typeSource != null && typeTarget != null && typeSource.FullName == typeTarget.FullName) if (typeSource.IsClass && !typeSource.Namespace.Equals("System", StringComparison.InvariantCulture)) { PropertyInfo[] propertyList = typeSource.GetProperties(); for (int index = 0; index < propertyList.Length; index++) { Type tempPropertySourceValueType = null; object tempPropertySourceValue = null; Type tempPropertyTargetValueType = null; object tempPropertyTargetValue = null; //get rid of indexers if (propertyList[index].GetIndexParameters().Length == 0) { tempPropertySourceValue = propertyList[index].GetValue(source, null); tempPropertyTargetValue = propertyList[index].GetValue(target, null); } if (tempPropertySourceValue != null) tempPropertySourceValueType = tempPropertySourceValue.GetType(); if (tempPropertyTargetValue != null) tempPropertyTargetValueType = tempPropertyTargetValue.GetType(); //if the property is a list IList ilistSource = tempPropertySourceValue as IList; IList ilistTarget = tempPropertyTargetValue as IList; if (ilistSource != null || ilistTarget != null) { if (ilistSource != null) ilistSource.MergeList(ilistTarget); else propertyList[index].SetValue(source, ilistTarget, null); } //if the property is a Dto else if (tempPropertySourceValue != null || tempPropertyTargetValue != null) { if (tempPropertySourceValue != null) tempPropertySourceValue.MergeObject(tempPropertyTargetValue); else propertyList[index].SetValue(source, tempPropertyTargetValue, null); } } } } return source; } } However, this works when the source property is null, if target has it, it will copy that to source. IT can still be improved to merge when inconsistencies are there e.g. if FirstName="Tiju" and FirstName="John" Any commments appreciated. Thanks TJ

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  • Use decorator and factory together to extend objects?

    - by TheClue
    I'm new to OOP and design pattern. I've a simple app that handles the generation of Tables, Columns (that belong to Table), Rows (that belong to Column) and Values (that belong to Rows). Each of these object can have a collection of Property, which is in turn defined as an enum. They are all interfaces: I used factories to get concrete instances of these products, depending on circumnstances. Now I'm facing the problem of extending these classes. Let's say I need another product called "SpecialTable" which in turn has some special properties or new methods like 'getSomethingSpecial' or an extended set of Property. The only way is to extend/specialize all my elements (ie. build a SpecialTableFactory, a SpecialTable interface and a SpecialTableImpl concrete)? What to do if, let's say, I plan to use standard methods like addRow(Column column, String name) that doesn't need to be specialized? I don't like the idea to inherit factories and interfaces, but since SpecialTable has more methods than Table i guess it cannot share the same factory. Am I wrong? Another question: if I need to define product properties at run time (a Table that is upgraded to SpecialTable at runtime), i guess i should use a decorator. Is it possible (and how) to combine both factory and decorator design? Is it better to use a State or Strategy pattern, instead?

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  • bootstrap: Uncaught TypeError: Object [object Object] has no method 'tooltip', 'typeahead'

    - by DarkKnightFan
    I am trying to use the tooltip, typeahead, datepicker features of bootstrap. But I keep getting these errors in the console! Uncaught TypeError: Object [object Object] has no method 'tooltip' Uncaught TypeError: Object [object Object] has no method 'typeahead' This is how my imports look like: <link href="css/bootstrap.css" rel="stylesheet"> <link href="css/datepicker.css" rel="stylesheet"> <link href="css/bootstrap-responsive.css" rel="stylesheet"> <script type="text/javascript" src="js/jquery-1.8.0.js"></script> <script type="text/javascript" src="js/bootstrap.js"></script> <script type="text/javascript" src="js/bootstrap-datepicker.js"></script> <script type="text/javascript" src="js/bootstrap-typeahead.js"></script> <script type="text/javascript" src="js/highcharts.js"></script> <script type="text/javascript" src="js/exporting.js"></script> <link type="text/css" rel="stylesheet" href="css/jquery.dropdown.css" /> <script type="text/javascript" src="js/jquery.dropdown.js"></script> Some sample code: <a class="btn btn-success" data-toggle="modal" href="#payments" rel="tooltip" data-placement="top" title="Record your payments"> <i class="icon-check icon-white"></i> Payments</a> $("#payments").tooltip('show'); Similarly I have code for datepicker and typeahead. any solution?

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  • Uncaught TypeError: Property 'dist2' of object [object Object] is not a function

    - by Radu Vlad
    I have this functions that should return me the distance from point p to segment line v-w. The problem i have is after some time i receive the following error: Uncaught TypeError: Property 'dist2' of object [object Object] is not a function. I receive it in distToSegmentSquared directly,not even calling the function dist2().Is it any other dist2() anywhere in jquery?I found none... function sqr(x) { return x * x; } function dist2(v, w) { console.log(v); console.log(w); return sqr(v.x - w.x) + sqr(v.y - w.y); } function distToSegmentSquared(p, v, w) { var l2 = dist2(v, w); if (l2 == 0) return dist2(p, v); var t = ((p.x - v.x) * (w.x - v.x) + (p.y - v.y) * (w.y - v.y)) / l2; if (t < 0) return dist2(p, v); if (t > 1) return dist2(p, w); return dist2(p, {x: v.x + t * (w.x - v.x), y: v.y + t * (w.y - v.y)}); } function distToSegment(p, v, w) { return Math.sqrt(distToSegmentSquared(p, v, w)); } The values that are given in for that error are: p: Object x: 461 y: 333 v: Object x: 80 y: 120 w: Object x: 260 y: 120

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  • use .net webbrowser control by multithread, throw "EXCEPTION code=ACCESS_VIOLATION"

    - by user1507827
    i want to make a console program to monitor a webpage's htmlsourcecode, because some of the page content are created by some javescript, so i have to use webbrowser control. like : View Generated Source (After AJAX/JavaScript) in C# my code is below: public class WebProcessor { public string GeneratedSource; public string URL ; public DateTime beginTime; public DateTime endTime; public object GetGeneratedHTML(object url) { URL = url.ToString(); try { Thread[] t = new Thread[10]; for (int i = 0; i < 10; i++) { t[i] = new Thread(new ThreadStart(WebBrowserThread)); t[i].SetApartmentState(ApartmentState.STA); t[i].Name = "Thread" + i.ToString(); t[i].Start(); //t[i].Join(); } } catch (Exception ex) { Console.WriteLine(ex.ToString()); } return GeneratedSource; } private void WebBrowserThread() { WebBrowser wb = new WebBrowser(); wb.ScriptErrorsSuppressed = true; wb.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler( wb_DocumentCompleted); while(true ) { beginTime = DateTime.Now; wb.Navigate(URL); while (wb.ReadyState != WebBrowserReadyState.Complete) { Thread.Sleep(new Random().Next(10,100)); Application.DoEvents(); } } //wb.Dispose(); } private void wb_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e) { WebBrowser wb = (WebBrowser)sender; if (wb.ReadyState == WebBrowserReadyState.Complete) { GeneratedSource= wb.Document.Body.InnerHtml; endTime = DateTime.Now; Console.WriteLine("WebBrowser " + (endTime-beginTime).Milliseconds + Thread.CurrentThread.Name + wb.Document.Title); } } } when it run, after a while (20-50 times), it throw the exception like this EXCEPTION code=ACCESS_VIOLATION (null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(nul l)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(n ull)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null) (null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(null)(nul l)(null)BACKTRACE: 33 stack frames: #0 0x083dba8db0 at MatchExactGetIDsOfNames in mshtml.dll #1 0x0879f9b837 at StrongNameErrorInfo in mscorwks.dll #2 0x0879f9b8e3 at StrongNameErrorInfo in mscorwks.dll #3 0x0879f9b93a at StrongNameErrorInfo in mscorwks.dll #4 0x0879f9b9e0 at StrongNameErrorInfo in mscorwks.dll #5 0x0879f9b677 at StrongNameErrorInfo in mscorwks.dll #6 0x0879f9b785 at StrongNameErrorInfo in mscorwks.dll #7 0x0879f192a8 at InstallCustomModule in mscorwks.dll #8 0x0879f19444 at InstallCustomModule in mscorwks.dll #9 0x0879f194ab at InstallCustomModule in mscorwks.dll #10 0x0879fa6491 at StrongNameErrorInfo in mscorwks.dll #11 0x0879f44bcf at DllGetClassObjectInternal in mscorwks.dll #12 0x089bbafa at in #13 0x087b18cc10 at in System.Windows.Forms.ni.dll #14 0x087b91f4c1 at in System.Windows.Forms.ni.dll #15 0x08d00669 at in #16 0x08792d6e46 at in mscorlib.ni.dll #17 0x08792e02cf at in mscorlib.ni.dll #18 0x08792d6dc4 at in mscorlib.ni.dll #19 0x0879e71b4c at in mscorwks.dll #20 0x0879e896ce at in mscorwks.dll #21 0x0879e96ea9 at CoUninitializeEE in mscorwks.dll #22 0x0879e96edc at CoUninitializeEE in mscorwks.dll #23 0x0879e96efa at CoUninitializeEE in mscorwks.dll #24 0x0879f88357 at GetPrivateContextsPerfCounters in mscorwks.dll #25 0x0879e9cc8f at CoUninitializeEE in mscorwks.dll #26 0x0879e9cc2b at CoUninitializeEE in mscorwks.dll #27 0x0879e9cb51 at CoUninitializeEE in mscorwks.dll #28 0x0879e9ccdd at CoUninitializeEE in mscorwks.dll #29 0x0879f88128 at GetPrivateContextsPerfCounters in mscorwks.dll #30 0x0879f88202 at GetPrivateContextsPerfCounters in mscorwks.dll #31 0x0879f0e255 at InstallCustomModule in mscorwks.dll #32 0x087c80b729 at GetModuleFileNameA in KERNEL32.dll i have try lots of methods to solve the problem, finally, i found that if i thread sleep more millseconds, it will run for a longer time, but the exception is still throw. hope somebody give me the answer of how to slove ... thanks very much !!!

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  • PHP Object References in Frameworks

    - by bigstylee
    Before I dive into the disscusion part a quick question; Is there a method to determine if a variable is a reference to another variable/object? For example $foo = 'Hello World'; $bar = &$foo; echo (is_reference($bar) ? 'Is reference' : 'Is orginal'; I have been using PHP5 for a few years now (personal use only) and I would say I am moderately reversed on the topic of Object Orientated implementation. However the concept of Model View Controller Framework is fairly new to me. I have looked a number of tutorials and looked at some of the open source frameworks (mainly CodeIgnitor) to get a better understanding how everything fits together. I am starting to appreciate the real benefits of using this type of structure. I am used to implementing object referencing in the following technique. class Foo{ public $var = 'Hello World!'; } class Bar{ public function __construct(){ global $Foo; echo $Foo->var; } } $Foo = new Foo; $Bar = new Bar; I was surprised to see that CodeIgnitor and Yii pass referencs of objects and can be accessed via the following method: $this->load->view('argument') The immediate advantage I can see is a lot less code and more user friendly. But I do wonder if it is more efficient as these frameworks are presumably optimised? Or simply to make the code more user friendly? This was an interesting article Do not use PHP references.

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  • Use a subclass object to modify a protected propety within its superclass object

    - by gadmeer
    Sorry for the crappy title I failed to think of a better version for my Java question. I am right now using Java version: 1.6.0_18 and Netbeans version: 6.8 Now for the question. What I've done is created a class with only one protected int property and next I made a public method to Set the int property to a given value. Then I made an object of that class and used said public method to set the int property to 5. Now I need your help to create another class that will take said object and expose it's protected int property. The way I could think of doing this was to create a sub class to inherit said class and then create a method to Get the int property of the super class. I kind of succeeded to create the code to Get the int property but now I can't figure out how to use this new sub class to reference the object of the super class. Here are the 2 classes I have thus far: public class A { protected int iNumber; public void setNumber ( int aNumber ) { iNumber = aNumber; } } public class B extends A { public int getNumber() { return super.iNumber; } } I created an object of 'A' and used its method to set its property to 5, like this: A objA = new A(); objA.setNumber ( 5 ); Now I want to create an object of 'B' to output the int stored within the property of 'objA'. I've tried to run this code: B objB = (B) objA; String aNumber_String = String.valueOf( objB.getNumber() ); System.out.println( aNumber_String ); but I got the error: "java.lang.ClassCastException" on the first line B objB = (B) objA; Please is there anyway of doing what I am trying to do? P.S. I am hoping to make this idea work because I do not want to edit class A (unless I have no choice) by giving it a getter method. P.P.S Also I know it's a 'bad' idea to expose the property instead of making it private and use public setter / getter methods but I like it this way :). Edit: Added code tags

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