Calling a method from object o

hi
event.getsource() returned a variable of type object. But in fact, this object is of type JTextField.
Now, I want to call : the method getName of this returned object.
This doesn't work:
JTextField tf = (JTextField)e.getSource();
tf.getName();
it allways returns null.
what am i doing wrong?
Thank you!
Christian

if tf.getName() returns null (rather than throwing a NullPointerException which is different) then the reason is that the name of the returned field IS null.
Are you sure you didn't mean to call tf.getText() ?
D.

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Calling a method from a super class

Hello, I'm trying to write a program that will call a method from a super class. This program is the test program, so should i include extends in the class declaration? Also, what code is needed for the call? Just to make things clear the program includes three different types of object classes and one abstract superclass and the test program which is what im having problems with. I try to use the test program to calculate somthing for each of them using the abstract method in the superclass, but its overridden for each of the three object classes. Now to call this function what syntax should I include? the function returns a double. Thanks.

Well, this sort of depends on how the methods are overridden.
public class SuperFoo {
public void foo() {
     //do something;
public void bar(){
     //do something
public class SubFoo extends SuperFoo {
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      //do something different that overrides foo()
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      foo(); //calls method in this (sub) class
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}However, if you have a superclass with an abstract method, then all the subclasses implement that same method with a relevant implementation. Since the parent method is abstract, you can't make a call to it (it contains no implementation, right?).

Calling a method from another class... that requires variables?

I'm calling a method from another class to change the date (its a date object) in another class.
I keep getting the error 'setDate(int,int,int) in Date cannot be applied to ()'
My code is:
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cycleDate.setDate();
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f1d wrote:
I'm calling a method from another class to change the date (its a date object) in another class.
I keep getting the error 'setDate(int,int,int) in Date cannot be applied to ()'
My code is:
public int changeDate()
cycleDate.setDate();
}I'm guessing I need to pass 3 parameters (day, month, year), seems that way from the error you posted
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setDate(16, 6, 2008);
I have tried, but then I get errors such as ')' expected?
Any ideas! :Dyou need to post your code if you're getting specific errors like that.
but typically ')' expected means just that, you have too many or not enough parenthesis (or in the wrong place, etc.)
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Calling a method from another class or accessing a component from another

Hi all
im trying to make a find/replace dialog box
my main application form has a jtextpane and when i open up the find and replace dialog box it has two textboxes (find and replace)
now i have the code to do the finding on my jtextpane but how do i call that code to do the find method?
I have tried having the code in my main application class but then how do i call that method from my dialog box class?
ive also tried having the code in my dialog box class, but then how to i tell it to work on my jtextpane which is in my main ap class?

well if someone had been nice enough to provide me
with a tutorial i wouldnt have gotten into this
muddle, no need to be rude is there!I'm not rude. And you also wouldn't have gotten into the muddle if you searched yourself. This site provides many very good tutorials about all kinds of stuff.
http://java.sun.com/docs/books/tutorial/java/javaOO/classes.htmlAmong other things, it mentions that "static" defines everything that belongs to a class, as opposed to an object.

EJB 3.1 @Asynchronous and calling other methods from within

Hey all,
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None the less, EJB 3.1 adds the async capability and I am now looking to use this. From my servlet I use @EJB to access the session bean, and call an async method. My servlet returns right away as it should. From the async method I do some work and using an entity bean store results, so I don't need to return a Future object. In fact, my ejb then makes an HttpClient call to another servlet to notify it that the result is ready.
My main question though, is if it's ok to call other methods from the async method that are not declared @Asynchronous. I presume it is ok, as the @Asynchronous just enables the container to spawn a thread to execute that method in. But I can't dig up any limitations on the code within an async method.. whether or not it has restrictions on the container services, is there anything wrong with using HttpClient to make a request from the method.. and making calls to helper methods within the bean that are not async.
Thanks.

851827 wrote:
Hey all,.. from what I've read the main concern is that the container maintains threads and your own threads could mess up the container somehow. I can only guess that this might be possible if your threads use the container services in some way.. but if anyone could enlighten me on the details as to why this is bad, that would be great.
Yes since the EE spec delegated thread management to conatiners, the container might assume that some info is available in the thread context that you may not have made available to your threads.
Also threading is a technical implementation detail and the drive with the EE spec is that you should concentrate on business requirements and let the container do the plumbing part.
If you were managing your own threads spawned from EJBs, you'd have to be managing your EJBs' lifecycle as well. This would just add to more plumbing code by the developer and typically requires writting platform specific routines which the containers already do anyway.
>
None the less, EJB 3.1 adds the async capability and I am now looking to use this. From my servlet I use @EJB to access the session bean, and call an async method. My servlet returns right away as it should. From the async method I do some work and using an entity bean store results, so I don't need to return a Future object. In fact, my ejb then makes an HttpClient call to another servlet to notify it that the result is ready.
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Thanks.If you want to be asynchronous without caring about a return value then just use MDBs.
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Why do you need to make the call to the servlet from the EJB? Makes it difficult to know who is the client here. Better use the Future objects and let the initial caller delegate to the other client components as needed.

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The issue I am facing is the following :
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In an WPF Desktop application, it would not be an issue because a WebBrowser
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void MainPage_Loaded(object sender, RoutedEventArgs e)
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private async void webView_ScriptNotify(object sender, NotifyEventArgs e)
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Hi ,
I want to call a method from a 'class interface' in a BADI .
Class Interface -- /SAPSRM/CL_PDO_DO_BASE
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Goto EDIT-> Pattern ->ABAP Object Patterns, Give class name , instance name and method, you got the required code.
Thanks,
Prasad.

Call Java method from c/c++ from native thread

Hi,
I know how to call a method from c/c++ with jni back to Java
but this fails when I try to do this from a native thread.
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Ok, problem has been solved
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Can I call Java Methods from Oracle Stored Procedures? I have a Java framework that logs events and would like to reuse it for logging events that occur in stored procedures.
null

You need to publish java class methods to plsql.
Attached below is some information.
Although both PL/SQL modules and Java classes are stored in the database
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Additional examples in subsequent sections illustrate some of these options.
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Hi,
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I'm having difficulties in calling a method from my class called Cabin to my main. Here's the code in my main              if(this is where i want my method hasKitchen() from my Cabin class)
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This is pretty basic stuff but i can't seem to get it right. I am calling a method from another file. The other file IS located in the same folder BUT when i compile i get errors
"cannot find symbol" <===referring to limit and sieve i believe.
The method name is "sieve" the file name is "PrimeSieve2008" and "limit" is the variable in brackets in the real method.
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Alex
Edited by: Simplistic2099 on Apr 3, 2008 7:47 PM
Edited by: Simplistic2099 on Apr 3, 2008 7:49 PM

Simplistic2099 wrote:
the other method runs fine:
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count = 0;
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candidate++;
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I really am clueless here.in this one you are passing in limit.
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Use the spring component context in soa suite instead of ejb. Look for documentation in soa suite developer guide. Only if you have existing ejbs then use ejb adapters.
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Message was edited by: VikramFusionApplied

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