Name: sdR10048 Date: 12/29/2000



The javadoc for java.beans.EventSetDescriptor says:

=(1)==============================================================

public EventSetDescriptor(Class sourceClass,
                          String eventSetName,
                          Class listenerType,
                          String[] listenerMethodNames,
                          String addListenerMethodName,
                          String removeListenerMethodName,
                          String getListenerMethodName)
                   throws IntrospectionException
This constructor creates an EventSetDescriptor from scratch using string names.
Parameters:
sourceClass - The class firing the event.
eventSetName - The programmatic name of the event set. Note that this
should normally start with a lower-case character.
listenerType - The Class of the target interface that events will get delivered to.
listenerMethodNames - The names of the methods that will get called
when the event gets delivered to its target listener interface.
addListenerMethodName - The name of the method on the event source
that can be used to register an event listener object.
removeListenerMethodName - The name of the method on the event source
that can be used to de-register an event listener object.
getListenerMethodName - The method on the event source that can be
used to access the array of event listener objects.
Throws:
IntrospectionException - if an exception occurs during introspection.
Since:
1.4

=(2)==============================================================

public EventSetDescriptor(String eventSetName,
                          Class listenerType,
                          Method[] listenerMethods,
                          Method addListenerMethod,
                          Method removeListenerMethod,
                          Method getListenerMethod)
                   throws IntrospectionException
This constructor creates an EventSetDescriptor from scratch using
java.lang.reflect.Method and java.lang.Class objects.
Parameters:
eventSetName - The programmatic name of the event set.
listenerType - The Class for the listener interface.
listenerMethods - An array of Method objects describing each of the
event handling methods in the target listener.
addListenerMethod - The method on the event source that can be used to
register an event listener object.
removeListenerMethod - The method on the event source that can be used
to de-register an event listener object.
getListenerMethod - The method on the event source that can be used to
access the array of event listener objects.
Throws:
IntrospectionException - if an exception occurs during introspection.
Since:
1.4
------------------------------------------------------------
It says:

getListenerMethod - The method on the event source that can be used to
access the array of event listener objects.

It is understood that output of this method is XXXListener[],
but it is not clear how many input parameters should have
getListenerMethod. Currently method with one input parameter
expected. Should be stated in javadoc. See expample.

Simple test that demonstrate current behaviour:
-Test2.java-------------------------------------------------
import java.beans.*;
import java.awt.event.*;
import java.lang.reflect.*;

public class Test2 {
    static String listenerMethodNames[] = {
        "fakeChanged"
    };

    public void addFakeListener(ActionListener l) {
    }

    public void removeFakeListener(ActionListener l) {
    }

    public void fakeChanged(ActionEvent e) {
    }

    // this is it: jdk says it should have 1 arg
    public Method[] getFakeListener() {
        return null;
    }

    public static void main(String[] args) {
        try {
            new EventSetDescriptor(Test2.class,
                          "Happy New Year",
                          Test2.class,
                          listenerMethodNames,
                          "addFakeListener",
                          "removeFakeListener",
                          "getFakeListener");
        } catch (IntrospectionException e) {
            System.out.println(e);
        }
    }
}
------------------------------------------------------------
Output:
] dsv@falcon ~/tmp
] java -version
java version "1.4.0-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta-b46)
Java HotSpot(TM) Client VM (build 1.4beta-B45, mixed mode)

] dsv@falcon ~/tmp
] javac Test2.java

] dsv@falcon ~/tmp
] java Test2
java.beans.IntrospectionException: No method "getFakeListener" with 1 arg(s) of matching types.

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