Extending classes with [Bindable]

Let's say I have a class that looks like this:
package
    [Bindable]
    public class models
        public function func1():void
then I am extending this class:
package
     [Bindable] // Do I ned this?
    public class model extends models
        public function model()
            super();
Do I have to repeat   [Bindable] for every class based on models class?
Thanks

If you want your child class to have its own or overriden bindable properties - yes, you do.

Similar Messages

[svn:osmf:] 11139: Extending class with a 'processLoadingState' stub, invoked when load state is set to LOADING.

Revision: 11139
Author:   [email protected]
Date:     2009-10-26 03:02:38 -0700 (Mon, 26 Oct 2009)
Log Message:
Extending class with a 'processLoadingState' stub, invoked when load state is set to LOADING.
Modified Paths:
    osmf/trunk/framework/MediaFramework/org/osmf/media/LoadableMediaElement.as

Strobe was used to verify that the problem was not with my OSMF implementation. Since the results were the same, I am more supsicious of OSMF itself or the underlying AIR framework than the player implementation. Either way, the information I've seen says that progressive download of h.264 video is supported on mobile devices with AIR. It would appear that this is not true in all cases.
The issue has not been observed on not occur on the desktop. It only occurs with StageVideo enabled playback with autoplay on.
In the actual product the videos play one at a time. Once the user has finished with a video, the player clears the references to the media. These are OSMF calls; the media assigned to the player is nulled. If this is not sufficient for garbage collection, then I am at a loss as to how to proceed. My test uses four videos that are roughly 1 MB. If there is a memory use problem, then it would appear something is broken in AIR or OSMF.
I want to be sure I report this correctly. The code involved is more than a snippet, it's a media player designed to be embedded in an app. Do I need to include the complete implementation or will a description be sufficient?

Extending classes with private methods?

my understanding of extending classes is that you gain all the functions and methods of that class thus You could over ride any one of them. How ever I am confused on weather or not you inherit and can over ride private methods of the class you are extending or if you have to have all methods public in an extended class.
hope that makes sense, an example can bee seen bellow.
package
     public class Class1
          public function apples():void
               //some code
          private fnctuin bananas():void
               //more code
package
     public class Class2 extends Class 1
          override public function apples():void
               //i changed code
          //can I over ride bananas?

you can only override methods that would be inherited. a private method won't be inherited:
http://www.kirupa.com/forum/showthread.php?223798-ActionScript-3-Tip-of-the-Day/page5

Extending classes with generics

I have a class, TreeNode, with a List containing more instances of itself. If I want to then extend this class as QuadTreeNode, the getChild method still returns a TreeNode. Is there anyway to make any classes extending this to return their own type or do I just need to redefine the Method getChild with return type QuadTreeNode?
public class TreeNode{
     private ArrayList<TreeNode> children = new ArrayList<TreeNode>();
     public TreeNode getChild( int i ) {
          return children.get(i);
}Sorry if this is a basic question, I'm trying hard to get to grips with this generics stuff.
Thanks a million for any help
Jay

To answer your question properly, too few context information is given.
In the general way you ask, the answer is no. I assume you would do a call to super.getChild(i), which returns a TreeNode and no QuadTreeNode. So you would at least have to cast the result to QuadTreeNode to make use of covariant-return.
So far, this is no Generics issue, btw.
Ask yourself if:
1. QuadTreeNode really is a TreeNode in your application.
2. TreeNode really is a concrete class or an interface.
3. If you might have the need for an abstract, generic class being super of TreeNode and QuadTreeNode.
There maybe more or fewer questions being set in the right context.

Can not filter the data with the extended class

Hi,
I have a quick question about PortableObject format. I have created a class which extends PortableObject interface and implemented serializer methods as well. I have updated it in the pof-config.xml file as well. If I insert the objects of this type of object in the cache, they get inserted properly and I can filter the values based on the getters defined in the class. Everything works fine here.
Now, I am trying to extend the existing class that I have. We have our custom API which we have built for our domain objects. I need to store these objects in the cache. So, naturally I need to implement PortableObject interface to do that. So, instead of creating a new class with new set of getters and setters and local fields, I am extending our domain class to create a new class which implements PortableObject interface. Instead of defining the local fields and getters and setters i am reusing the ones provided by my existing class. Now, I can insert the objects of the new class to the cache. But I can not filter the values for the objects of this new class.
Let me show you what exactly I am trying to achieve by giving a small example:
Domain Class:
class Person
private String person_name;
*public String getPerson_name() {return person_name;}*
*public String setPerson_name(person_name) {this.person_name = person_name;}*
The new class implementing PortableObject interface:
class ExtPerson extends Person implements PortableObject
public static final PERSON_NAME = 0;
*public void readExternal(PofReader reader) throws IOException{*
setPerson_name(reader.readString(PERSON_NAME));
*public void writeExternal(PofWriter writer) throws IOException{*
writer.writeString(PERSON_NAME, getPerson_name());
*// And HashCode, Equals and ToString methods, all implemented using the getter from the Person class*
So, if I create a new class ExtPerson without extending the Person class and write all the methods, store the objects in the cache and perform the following query, I get the size printed
System.out.println((cache.entrySet(new EqualsFilter("getPerson_name","ABC"))).size());
But if I use the extended class and insert the values into the cache and if I use the same query to filter, I get 0 printed on the console.
System.out.println((cache.entrySet(new EqualsFilter("getPerson_name","ABC"))).size());
So, can anyone tell what exactly is causing this?
Thanks!

Well, just a quick question. It seems that I can not get ContainsAnyFilter or ContainsAllFilter working.
EqualsFilter is actually working properly.
I am preparing a Set of Strings and passing it to ContainsAnyFilter or ContainsAllFilter and it is returning me 0 records.
E.g.:
Set<String> setStr = new HashSet<String>();
setStr.add("ABC");
setStr.add("DEF");
System.out.println((cache2.entrySet(new ContainsAnyFilter("getPerson_name", setStr))).size());
I get 0 in my output
If I try this:
System.out.println((cache.entrySet(new EqualsFilter("getPerson_name","ABC"))).size());
System.out.println((cache.entrySet(new EqualsFilter("getPerson_name","DEF"))).size());
I get 1 for each of the query.
If I club all these EqualsFilter in a Filter[] array and create an AnyFilter or AllFilter and pass it to the query, it works fine.
List<Object> lst = new ArrayList<Object>();
          lst.add("ABC");
          lst.add("DEF");
Filter[] filter = new Filter[lst.size()];
     for(int i=0;i<lst.size();i++)
          filter[i] = new EqualsFilter("getPerson_name",lst.get(i).toString());
AnyFilter fil = new AnyFilter(filter);
System.out.println((cache4.entrySet(fil)).size());
I get the desired result here, which is 2.
Am I missing something here?

Can't get extended class to work with asbstract class

I am having trouble working an extended class to work with my base abstract class. I keep getting this error message: "Fiction.java:4: invalid method declaration; return type required" public FictionBook()" Can someone give me some advice and or guidance on what I need to do? Thanks.
Here is my abstract class:
import javax.swing.*;
public abstract class Book
     protected String bookTitle;
     protected double bookPrice;
     public abstract double setPrice();
public Book()
          setBookPrice();
public double getBookPrice()
          return bookPrice;
public abstract void setBookPrice();
Here is the extended class that I have:
import javax.swing.*;
public class Fiction extends Book
     public Fiction()
          super();
          setBookPrice();
     public void setBookPrice();
          bookPrice = 24.95;
     public String toString()
          return("Fiction Book Price is $" + bookPrice);
}

Fiction.java:2: Fiction is not abstract and does not override abstract method setPrice() in BookThis one is pretty straightfoward: Book declares an abstract setPrice() method. In effect is promises "every concrete subclass of Book will define an implementation of setPrice()". But your Fiction class does not do this - it does not give an implementation of setPrice() even though as a Book it is required to do so. That is what the compiler is complaining about.
Fiction.java:6: call to super must be first statement in constructorThis one is slightly cryptic. If you use super() it must be as the first line of a constructor. You are using it as the first line of Fiction() so that looks OK - until you realise that Fiction() is not a constructor! That's because you declare it as a method returning void. Remove the "void" and the compiler will recognise it as a constructor and will be happy about your use of super().
Edited by: pbrockway2 on Sep 13, 2008 12:13 PM
Just a general point: it might be worth writing very brief comments for your abstract class to say what the methods are supposed to do. It isn't really clear what setBookPrice() is supposed to do given that it isn't passed any argument. Likewise setPrice(), how does it differ from setBookPrice()? what is the double value that it returns?

Extending a class with a qualifier?

Hi,
i have a doubt regarding extending a class with qualifier(in Java)? to my knowledge it is not possible. but some one said this is possible ...
can some one lemme know..
Is it possible to extend a class with a qualifier?
i mean class A extends class B(privately/protectedly etc..)
class A extends private/protected B{}// is there a way to do some thing like this? can we
can v reduce the acess level while extending it (public to private) so that v can extends calss as if it is a private class..
Thanks
Kish.

I don't fully understand the question, but you can say:
public class B
private class A extends B
}or
public class B
private class A extends B
Except there are problems with that, class A would need a get method in order to get an instance of class A
Hope this helps,
Radish21

Extend standar class with new button(method)

Hi,
I want to create new button in standard class /SAPSRM/IF_PDO_AO_BP_BASE.
Does anyone know how to extend the class with a new button?
Very thanks.

I NEED TO CREATE NEW BUTTON IN THIS CLASS.
THE BUTTON MUST SHOW A POP-UP WHEN PARTNET HAVE DOCUMENT´S IN SYSTEM.
CAN YOU HELP ME?

'My Application Page' is not allowed here because it does not extend class 'System.Web.UI.Page'

I have a custom SharePoint 2010 solution that includes an aspx page. The aspx page in is in the /layouts folder within the solution and I created it by just adding an application page to the solution. I am trying to create a parent-child relationship between
two different lists in SharePoint. From the parent I have a custom button on the ribbon that creates a child item with the ID of the parent stamped on it.
The page is just a processing page that forwards on parameters from the parent to the new child item. (i.e. the ID value)
The code generated when I add the aspx page is below:
<%@ Assembly Name="$SharePoint.Project.AssemblyFullName$" %>
<%@ Import Namespace="Microsoft.SharePoint.ApplicationPages" %>
<%@ Register Tagprefix="SharePoint" Namespace="Microsoft.SharePoint.WebControls" Assembly="Microsoft.SharePoint, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<%@ Register Tagprefix="Utilities" Namespace="Microsoft.SharePoint.Utilities" Assembly="Microsoft.SharePoint, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<%@ Register Tagprefix="asp" Namespace="System.Web.UI" Assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" %>
<%@ Import Namespace="Microsoft.SharePoint" %>
<%@ Assembly Name="Microsoft.Web.CommandUI, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="processingpage.aspx.cs" Inherits="MY.Solution.Layouts.MY.Solution.processingpage" MasterPageFile="~/_layouts/application.master" %>
<asp:Content ID="PageHead" ContentPlaceHolderID="PlaceHolderAdditionalPageHead" runat="server">
</asp:Content>
<asp:Content ID="Main" ContentPlaceHolderID="PlaceHolderMain" runat="server">
</asp:Content>
<asp:Content ID="PageTitle" ContentPlaceHolderID="PlaceHolderPageTitle" runat="server"> Processing Page </asp:Content>
<asp:Content ID="PageTitleInTitleArea" ContentPlaceHolderID="PlaceHolderPageTitleInTitleArea" runat="server" > Processing Page </asp:Content>
The code behind is as follows:
using System;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;
using Microsoft.SharePoint.WebControls;
using Microsoft.SharePoint.Utilities;
using System.Reflection;
namespace MY.Solution.Layouts.MY.Solution
public partial class processingpage : LayoutsPageBase
protected void Page_Load(object sender, EventArgs e)
try
//Get a reference to the SPWeb object
SPWeb oWeb = SPContext.Current.Web;
//Use the Parameters That Are Passed In
SPList thisList = oWeb.Lists[new Guid(Request.QueryString["List"])];
SPListItem thisItem = thisList.GetItemById(int.Parse(Request.QueryString["ID"]));
sContentType = thisItem["ContentType"].ToString();
sContentTypeID = thisItem.ContentTypeId.ToString();
if (sContentType == "Some Content Type")
sContentTypeID = "";
sAIID = thisItem["ID"].ToString();
//Redirect to newform.aspx with the Appropriate parameters.
Context.Response.Redirect(oWeb.Url + "/Lists/Blist" + "/NewForm.aspx?AIID=" + sAIAuditID.ToString() + "&ContentTypeId=" + sContentTypeID + "&ParentItemID" + Context.Request["ID"]);
else if (sContentType == "Some Content Type")
sContentTypeID = "";
sAIID = thisItem["AIID"].ToString();
//Redirect to newform.aspx with the Appropriate parameters.
Context.Response.Redirect(oWeb.Url + "/Lists/AList" + "/NewForm.aspx?AIID=" + sAIID.ToString() + "&ContentTypeId=" + sContentTypeID + "&ParentItemID" + Context.Request["ID"]);
else if (sContentType == "Some Content Type")
sContentTypeID = "";
sAICID = thisItem["AICID"].ToString();
//Redirect to newform.aspx with the Appropriate parameters.
Context.Response.Redirect(oWeb.Url + "/Lists/CList" + "/NewForm.aspx?AICID=" + sAICID.ToString() + "&ContentTypeId=" + sContentTypeID + "&ParentItemID" + Context.Request["ID"]);
else
LoggingService.LogError("MY.Solution - Processing Page", "No Applicable Content Type Found.");
catch (Exception ex)
LoggingService.LogError("My.Solution - Processing Page", ex.Message);
finally
//DO SOME FINAL THINGS HERE WHEN REQUIRED.
In the page I need to use Request.QueryString to get the values from the URL. But when I deploy the solution and load the page I get the error:
'MY.Solution.Layouts.MY.Solution.processingpage' is not allowed here because it does not extend class 'System.Web.UI.Page'.
When I change the line:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="processingpage.aspx.cs" Inherits="MY.Solution.Layouts.MY.Solution.processingpage" MasterPageFile="~/_layouts/application.master" %>
to inherit as follows:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="processingpage.aspx.cs" Inherits="Microsoft.SharePoint.WebControls.LayoutsPageBase" MasterPageFile="~/_layouts/application.master" %>
it does not work either.
If I change it to inherit like below:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="processingpage.aspx.cs" Inherits="System.Web.UI.Page" MasterPageFile="~/_layouts/application.master" %>
it also does not work.
What does this error actually mean? And why doesn't the default code generated by Visual Studio work?

@NadeemYousuf I have tried this too and it didn't work.
What does the error even mean? And why does the error appear with default Visual Studio code? In my example I have just added a basic application page with no other code in it and it still does not work.

NoClassDefFoundError extending class in separate JAR

I have a class Foo which gets called from my servlet (extends HttpServlet) class. Both Foo and the servlet class are located in WEB-INF/classes and are deployed as part of the war file. Class Foo extends class Bar, which is a different .jar file located in the /WEB-INF/lib directory of the webapp. When I attempt to create an instance of Foo, I get the following exception:
java.lang.NoClassDefFoundError: /general/client/common/beans/Bar
     at java.lang.ClassLoader.defineClass1(Native Method)
     at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
     at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
     at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
     at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
     at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
     at java.security.AccessController.doPrivileged(Native Method)
     at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
     at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1267)
     at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1198)
     at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
     at server.DBServlet.createFoo(DBServlet.java:236)
     at server.DBServlet.processInput(DBServlet.java:333)
     at server.DBServlet.doGet(DBServlet.java:154)
     at server.DBServlet.doPost(DBServlet.java:205)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
     at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:432)
     at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:541)
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
     at org.apache.catalina.authenticator.SingleSignOn.invoke(SingleSignOn.java:419)
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
     at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
     at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:667)
     at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
     at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
     at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
     at java.lang.Thread.run(Thread.java:595)
I'm running this on Windows, and found if I added the classpath the the jar file where the Bar class is located, that it worked fine. But my expectation is that the jar file should have been found because it is in the /WEB-INF/lib dir. There is a line the Tomcat docs that says:
"Last, any JAR containing servlet API classes will be ignored by the classloader. All other class loaders in Tomcat 5 follow the usual delegation pattern."
So maybe I need to do something special to load the Bar class, or there's something strange about the way the classes and jars are being loaded that I don't fully understand. I was able to instantiate the Bar class directly from w/in my servlet class, I just can't create an instance of the Foo class that is in /WEB-INF/classes along with the servlet class. So I'm not convinced that the Bar class or associated jar file isn't being loaded.
I don't want to have to set the classpath explicitly, so I'm looking for advice on why I'm getting this exception and how best to dynamically load the classes I need.
Thanks.
ab.

Thanks for hanging in there so far. Here's the specifics if you want to try to re-create this.
I have a webapp, which contains the class DBServlet:
package com.hm.dhca.server;
public class DBServlet extends HttpServlet
// Stuff
     public void processInput()
          Foo foo = new Foo();
The webapp also contains the class Foo:
package com.hm.dhca.common;
import com.general.client.common.beans.Bar;
public class Foo extends Bar
     public Foo()
          super();
          System.out.println("Foo");
Both of the classes are located in webapps\DHCA\WEB-INF\classes...
The Bar class is in a separate jar called HMJCommon.jar in the webapps\DHCA\WEB-INF\lib dir.
Class Bar looks like this:
package com.general.client.common.beans;
public class Bar
     public Bar()
          System.out.println("Bar");
DBServlet creates an instance of Foo as:
Foo foo = new Foo();
Which throws the Exception:
java.lang.NoClassDefFoundError: com/general/client/common/beans/Bar
     at java.lang.ClassLoader.defineClass1(Native Method)
     at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
     at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
     at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
     at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
     at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
     at java.security.AccessController.doPrivileged(Native Method)
     at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
     at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1267)
     at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1198)
     at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
     at com.hm.dhca.server.DBServlet.processInput(DBServlet.java:236)
     at com.hm.dhca.server.DBServlet.doGet(DBServlet.java:154)
     at com.hm.dhca.server.DBServlet.doPost(DBServlet.java:205)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
     at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:432)
     at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:541)
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
     at org.apache.catalina.authenticator.SingleSignOn.invoke(SingleSignOn.java:419)
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
     at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
     at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:667)
     at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
     at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
     at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
     at java.lang.Thread.run(Thread.java:595)
Clues:
1. All three classes exist in the locations specified above - I have checked this manually.
2. Within DBServlet, I can create an instance of Bar. But I cannot create an instance of Foo without the exception.
3. If I move the Foo class from package com.hm.dhca.common to package com.hm.dhca.server (same package as DBSerlvet), everything works fine.
4. If I modify Tomcat's classpath to include the HMJCommon.jar, it works fine (as previously discussed).
Theory:
I have a vague theory that what is happening is that two different webappclassloaders are loading the Foo and Bar classes, for whatever reason. As a result, they can't see each other, because neither is up the hierarchy tree from the other.
This does not explain how I can instantiate Bar from DBServlet, but not Foo.
Hope this helps. I think I've corrected previous mistake w/ removing too much from package naming. I'm resorting to the workaround in clue #3 for the moment. But it's not the correct solution, and it's showing that I don't really understand what's going on here.

Extending classes at runtime

Hi,
Is there a way to extend a class at runtime? What I'd like to do is the following:
I want to have a tabbed pane component that does not stretch its tabs when there are several lines of tabs. The stretching of the tabs is implemented in the UI component of JTabbedPane - and this depends on the look & feel - it can be MetalTabbedPaneUI, WindowsTabbedPaneUI, etc.
I want to extend the currently-used UI class (which is only known at runtime) with my own class that overrides a single method.
I can extend all those that I currently know and use some mapping from the currently used class to the one extending it - but tomorrow someone may install a new look & feel which uses a different UI component, for which I will not have an extending class.
Therefore, I'd like to find the currently used UI component class and extend it at runtime.
Thanks,
Shlomy

Shlomy-Reinstein wrote:
Thanks. It's a good solution, but it requires me to write wrappers for all the public methods of BasicTabbedPaneUI, doesn't it? All I'm interested in is to override a single method. If there is no easier way, that's okay, but since there are scripting languages that interface with Java (e.g. BeanShell), in which I can extend classes, I thought there should be an easy way to extend a class at runtime.You don't write code that is "easy". You write code that is correct.
If there are several different ways to write code which are all correct then you use other criteria to determine the best one. The first criteria is how much maintenance each would require. And how complex each solution would be. Complexity also impacts maintenance.
And nothing I have seen in this thread would suggest that anything but a wrapper is a correct solution. Certainly unless you can demonstrate that it would not work then I doubt anything would be better.
And using beanshell just so you don't have to type is definitely not the correct solution.

Passing Optional Parameter Via Extended Class Constructor

Following is a snippet of code I copied and have a question about when extending DataGridColumn class to sort numeric for colums that have numeric values:
CustomAdvancedDataGridColumn(columnName:String=null,numeric:Object=null)
super(columnName);
initCompare(numeric);
function initCompare(numeric:Object):void
if (numeric == NUMERIC) {
sortCompareFunction = numericCompare;
The extended class is supposed to receive variable "numeric" type Object in the constructor which is then supposed to be used in the initCompare function to determine if a column contains numeric values. This code didn't work for me as numeric variable remains null. To get it working I added a new public static const and private propery "numeric" and obtained it with get() set() to see if should the column should sort numeric. This works but you have to set the property in the extended datagrid column FLEX tag.
My question is how is the variable numeric in the code snippet above supposed to get it's new data for the initCompare function? I can't get it to be anything other than null.
Thanks for any insights...I'm new to FLEX.
Jason

Still searching for a solution.
Please note, that I'm using the syntax described in
<a href="http://help.sap.com/businessobject/product_guides/boexir31/en/xi3-1_url_reporting_opendocument_en.pdf">http://help.sap.com/businessobject/product_guides/boexir31/en/xi3-1_url_reporting_opendocument_en.pdf</a>
on page 65.
So did I get anything wrong? Help would be really appreciated, also Workarounds if there's no solution for the problem.

Authoring Tool "Inherit Class" vs "New Class" vs "Extended Class" Scenario Help

Hi Community,
I am currently creating the ground work needed to create Self Service Portal Request Offerings to be used by end users and then take that input and automate it with Orchestrator.
I'm pretty comfortable with the overall process of how this is done, but I was hoping to get guidance from the community to make sure that I don't waste my time by editing my existing management pack incorrectly from the beginning.
We currently have a Whole bunch of SR and IR Templates in a Management Pack - lets call it: "Company.Templates.MP" now what I want to do is edit this MP and add new List and String Properties to hold the responses provided from the
Self Service Portal so that I can use a Runbook Activity to feed these responses into Orchestrator.
Now what I have done is "Extended" the existing "Service Request" and "Incident" classes and created the new properties in each extended class. Now that I have Extended the default Classes I believe that the properties now apply
to EVERY existing and new SR and IR.
My question is... Do you think I have done this correctly?
I have a gut feeling that I have done it wrong and I should revert my MP changes and then instead of extending the existing IR and SR Classes which affect all existing Work Items, I should create a new SR and IR class which would then be used to create new
Templates which are then ONLY ones that contain the new properties that would be used for Runbook Automation.
The feedback I receive will be VERY MUCHLY appreciated...

Answering your implicit question in the title:
Inherit is where you create a new class that has all the properties of the parent and then some new ones also, but people can still use the parent for regular work. This is for specialization, like say you want a new type of incident to
cover firewall problems, and need new properties for the IP and Ports from the portal.
Extended would be where you add properties to a class that make sense for all of those and all inheriting classes. say the client has a cost of IT tracking system where every Incident and Service Request needs to be assigned a cost of effort
code, you would create two extensions for Incident and Service request, and point them at the same enum list. you wouldn't extend WorkItem, because changes, activities, released etc wouldn't use a simple cost estimate list value, and you wouldn't inherit off
of SR and IR because all user requests should have this property, even if some of them are blank
New would be a class from scratch that inherits from Entity. This is hardly ever what you want to do, because even completely new things are either work items or config items, and should, where ever possible, inherit from one of those
basil classes
Now to your explicit question: No, i think you've done exactly what the situation called for. every SR should have this value, even if it is empty for the historical items.
two side notes: 1) any item that refers to the base of an extension will continue to work as expected, but 2) Offerings are always the exception. The net of these two rule of thumb guidelines is that your existing templates should continue to work
without modification, but you may have to recreate the offering before you can use the new property in a question.
AFAIK you cannot extend an abstract calls (ex. Work Item), but I could be wrong.
http://codebeaver.blogspot.dk/

Unusual use of interface defining static factory class with getInstance

This question is prompted by a recent New to Java forum question ask about the differences between Interfaces and Abstract classes. Of course one of the standard things mentioned is that interfaces cannot actually implement a method.
One of my past clients, one of the 500 group, uses interfaces as class factories. The interface defines a pubic static class with a public static method, getInstance, that is called to generate instances of a class that implements the interface.
This architecture was very object-oriented, made good use of polymorphism and worked very well. But I haven't seen this architecture used anywhere else and it seemed a little convoluted.
Here is a 'pseudo' version of the basic interface template and use
-- interface that defines public static factory class and getInstance method
public interface abc {
    public static class FactoryClass
        public static abc getInstance ()
            return (abc) FactoryGenerator(new abcImpl(), abc.class);
-- call of interface factory to create an instance
abc myABC = abc.Factory.getInstance();1. Each main functional area ('abc' in the above) has its own interface factory
2. Each main functional area has its own implementation class for that interface
3. There is one generator (FactoryGenerator) that uses the interface class ('abc.class') to determine which implementation class to instantiate and return. The generator class can be configured at startup to control the actual class to return for any given interface.
I should mention that the people that designed this entire architecture were not novices. They wrote some very sophisticated multi-threaded code that rarely had problems, was high performance and was easy to extend to add new functionality (interfaces and implementing classes) - pretty much plug-n-play with few, if any, side-effects that affected existing modules.
Is this a best-practices method of designing factory classes and methods? Please provide any comments about the use of an architecture like this.

Thanks for the feedback.
>
I don't see how 'the generator class can be configured at startup to control the actual class to return for any given interface' can possibly be true given this pseudo-code.
>
I can see why that isn't clear just from what is posted.
The way it was explained to me at the time is that the interface uses standard naming conventions and acts like a template to make it easy to clone for new modules: just change 'abc' to 'def' in three places and write a new 'defImpl' class that extends the interface and the new interface and class can just 'plug in' to the framework.
The new 'defImpl' class established the baseline functionality that must be supported. This line
return (abc) FactoryGenerator(new abcImpl(), abc.class);uses the initial version of the new class that was defined, 'abcImpl()', when calling the FactoryGenerator and it acted as a 'minimum version supported'. The generator class could use configuration information, if provided, to provide a newer class version that would extend this default class. Their reasoning was that this allowed the framework to use multiple versions of the class as needed when bugs got fixed or new functionality was introduced.
So the initial objects would be an interface 'abc' and a class 'abcImpl'. Then the next version (bug fixes or enhancements) would be introduced by creating a new class, perhaps 'abcImpl_version2'. A configuration parameter could be passed giving 'abcImpl' as the base class to expect in the FactoryGenerator call and the generator would actually create an instance of 'abcImpl_version2' or any other class that extended 'abcImpl'.
It certainly go the job done. You could use multiple versions of the class for different environments as you worked new functionality from DEV, TEST, QA and PRODUCTION environments without changing the basic framework.
I've never seen any Java 'pattern' that looks like that or any pattern where an interface contained a class. It seemed really convoluted to me and seems like the 'versioning' aspect of it could have been accomplished in a more straightforward manner.
Thanks for the feedback. If you wouldn't mind expanding a bit on one comment you made then I will mark this ANSWERED and put it to rest.
>
I don't mind interfaces containing classes per se when necessary
>
I have never seen this except at this one site. Would you relate any info about where you have seen or used this or when it might be necessary?

Question about extending classes

Hi
I've created my own class that extends javax.swing.JTextField as follows:
public class myTextField extends javax.swing.JTextField{
     public myTextField(){
          super();
          initialize();
     protected void initialize()
          super.setEditable(false);
          super.setHorizontalAlignment(javax.swing.JTextField.LEFT);
          super.setBorder(null);
          super.setSelectionColor(null);
}Dunno if this is the best way to do it, but it works, so I'm happy!
My question is: Is it possible to have more than one definition in this class?
For example, a myTextField2 that extends JTextField with completly different attributes (eg, different back ground colour etc) or do I have to create a new class?

For example, a myTextField2 that extends JTextField
with completly different attributes (eg, different
back ground colour etc) No, but you can create another constructor that accepts different arguments.
public myTextField(Color c)Like that. By the way class names should start with an upper-case character.

Extending classes with [Bindable]

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