Implementing evetns in my own classes

I am currently developing a class that I want to enable with events so that consumers of my class can get feedback of class activity.
So consumers should be able to add listeners (containing callback methods) to instances of the class. Although my current class is GUI related (I am writing my own tablemodel) my issue is not limited to GUI development I think (therefore posted here and not in Swing forum).
So far I am a little familiar with Listener and Adapter classes but now the point:
Do I have to implement my own addBlaBlaListener and removeBlaBlaListener methods implementing my own methods to handle the list of current listeners (e.g. choosing the appropriate array, list, stack or whatever classes to store the references) or is there some ready-made-classes from the libraries that should/can be used?

tjacobs01 wrote:
Why do you need to create UI-style events?I am building my own Table model as the simple table model is too basic for my common needs. In that table model I need to provide events being fired when table cells change.
I highly recommend using the Observable/Observer pattern where possible. Otherwise, see an example for custom events in my InfoFetcher.FetcherListener interface
http://forums.sun.com/thread.jspa?threadID=759854&tstart=62264
I heard/read about the Observer and Observerable but when I searched for event handling I always found the methods I am currently trying. That's the only reason why I use that here - because this is what I found how others recommend to do it. If there is a better option - I am open and flexible - yet (in a year when everything was implemented probably not ;-) ).

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I read somewhere that As2 not allow to use uisbar in other type of class that extends movieclip or textfiled or you know what...
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You need to read the basics about Swing events.
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my_combo.addActionListener( new ActionListener() {
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Interfaces for your own classes - do you bother?

Hi All,
before anyone gets upset, I did post a shorter version this to the Java Prog forum a couple of days ago. I'm reposting here because the thread was pushed down the list just as comments were getting interesting, and I was tossing up which forum was most appropriate anyway...
OK, I'd like to pose a general question on the use of interfaces with your own classes. I am totally behind the concept of using appropriate interfaces for declaration of vars, parameters etc (i.e. use "List" rather than "Vector"), but what about your own classes?
If I have a class in my application that doesn't fit into any kind of framework or class hierarchy, subclass of object basically, should I write an interface with all the same method sigs and use that rather than the class for my vars, params etc? This would make things more flexible in future, enabling you to swap classes in and out of your app more easily.
Taking it a step further, how's this for a design methodology: For every class you write (once again classes that don't fit into your own or somebody else�s hierarchy or framework) do the following
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Cheers
Matt

Although the pattern you describes adds flexibility, it also adds complexety.
Imagine somebody is looking at your code and from what he sees he deducts that the next thing to look at is the concrete class which is used at a given place.
If you used an interface, he must find out which implementing class is actually used at this place. It's not a big thing, but if every single class has its seperate interface and factory I would consider it overkill ... after all you have to write all the boring code for this.
In the case of doubt I'd agree it's better to throw in an interface and a factory instead of refactoring thousand lines of codes afterwards. But if nothing hints toward a second implementation of the interface, or another reason for using an interface don't bother to write one.
As a general rule I use something like: Don't use a general rule. ;-)
Spieler

Problem with creating my own class...

Hi all,
Purpose with this program:
I want to create my own class StringThing which take a string parameter and transform the content toUpperCase().
I have created a simple class StringThing which look like this:
class StringThing {
public String upperize (String u) {
u.toUpperCase();
return u;
}And my class where I use the StringThing looks like this:
import java.io.*;
class UseStringThing{
public static void main (String arg[]) throws Exception {
BufferedReader keyboard = new BufferedReader(
new InputStreamReader(System.in));
String s,p;
System.out.prinln("write a sentence!");
s=keyboard.readLine();
StringThing thing = new StringThing();
p=thing.upperize(s);
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}Am I not supposed to transform my string parameter in my class by using for instance toUpperCase()? Or is there some fundamental rule or piece of code which I forgot?
Thanks in advance,
/Beginner-T-who-ripps-his-hear-over-this-small-problem

Strings cannot be modified. What this line does:
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return u.toUpperCase();
or
u = u.toUpperCase();

How can I create a new own class in WebDynpro?

I test the Web Dynpro for a while and found all the java classes were generated automatically. I've tried to create an own class. But after I rebuild the project, all of my own classes were cleared.

Hi
You can create your own class as mentioned in above replies or one more way,
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2. create seperate java project
rightclick on WDproject>properties>Projects>selectYourjavaProject>ok
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Abhijith YS

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Hi, all!
I read many previous topics in this forum but no one works for me!
Please someone help me!
I'm using Tomcat 4.1.12 and my JSP scripts work just fine, but I need to import my own .class file. I just don't know where to put it so Tomcat can find it!?
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plzz anser my qustion soon..

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run:
Exception in thread "main" java.lang.UnsatisfiedLinkError: cembedjava.CFunctions.nativePrint()V
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Thanks

Thanks guys,
I got it working... I had a problem with the declaration of the function in my .h and .c file. In the .h file everything was okay, but I had the wrong classname in the .c file. For some reason this still compiled but gave me the exception during runtime.
Is there also a possibility not to have to put in the class name in the function declaration, right now the function are declared as this:
JNIEXPORT void JNICALL Java_cembedjava_CFunctions_nativePrint
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Implementing evetns in my own classes

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