[Bug java/21065] New: javax.swing.event.EventListenerList.getListenerList() implemented wrong

[Bug java/21065] New: javax.swing.event.EventListenerList.getListenerList() implemented wrong

[gruni dot ca at gmail dot com]

I am using a custom Class wich throws events, by using this I rely on the
EventListenerList Class to hold my Eventlisteners. The Method getListenerList is
used by the method 

 protected void fireFooXXX() {
    // Guaranteed to return a non-null array
    Object[] listeners = listenerList.getListenerList();
    // Process the listeners last to first, notifying
    // those that are interested in this event
    for (int i = listeners.length-2; i>=0; i-=2) {
        if (listeners[i]==FooListener.class) {
            // Lazily create the event:
            if (fooEvent == null)
                fooEvent = new FooEvent(this);
            ((FooListener)listeners[i+1]).fooXXX(fooEvent);
        }
    }
}

which is the standard Method given in the API to fire Events to all
EventListeners. This Method relies on the correct implementation of
getListenerList() which should according to the API Documentation of Java by SUN
http://java.sun.com/j2se/1.5.0/docs/api/javax/swing/event/EventListenerList.html#getListenerList()
[quote]
getListenerList

public Object[] getListenerList()

    Passes back the event listener list as an array of ListenerType-listener
pairs. Note that for performance reasons, this implementation passes back the
actual data structure in which the listener data is stored internally! This
method is guaranteed to pass back a non-null array, so that no null-checking is
required in fire methods. A zero-length array of Object should be returned if
there are currently no listeners. WARNING!!! Absolutely NO modification of the
data contained in this array should be made -- if any such manipulation is
necessary, it should be done on a copy of the array returned rather than the
array itself.
[/quote]

The API doc says "Passes back the event listener list as an array of
ListenerType-listener pairs." my understanding of pairs is multiples of two, so
the EventListenerList can never contain 1 or 3 entries or any other odd number.
But when adding one Eventlistener to such a list it really just adds this
EventListener resulting in a getListenerList() which returns one Element, which
is simply wrong.

A Testcase will follow as soon as I have written one.

btw this is my system: WinXP SP2
                       gcj 4.0 20050324 from thisiscool.com

Regards,

Andreas

-- 
           Summary: javax.swing.event.EventListenerList.getListenerList()
                    implemented wrong
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P1
         Component: java
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: gruni dot ca at gmail dot com
                CC: gcc-bugs at gcc dot gnu dot org,java-prs at gcc dot gnu
                    dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21065

[Bug java/21065] javax.swing.event.EventListenerList.getListenerList() implemented wrong

[gruni dot ca at gmail dot com]

------- Additional Comments From gruni dot ca at gmail dot com  2005-04-17 00:45 -------
Created an attachment (id=8663)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=8663&action=view)
Simple Testcase showing that addind a EventListener increments the list by one

This is a testcase I wrote, I compiled it with 
gcj --main=GcjEventListenerListTest -o EventTest.exe
GcjEventListenerListTest.java
the output should be similar to JDK if implemented correctly
JDK output:
should be=2 is=2
should be=4 is=4
GCJ output:
should be=2 is=1
should be=4 is=2

That's all I have


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21065

[Bug java/21065] javax.swing.event.EventListenerList.getListenerList() implemented wrong

[gruni dot ca at gmail dot com]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Attachment #8663|Simple Testcase showing that|Simple Testcase showing that
        description|addind a EventListener      |adding a EventListener
                   |increments the list by one  |increments the list by one


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21065

[Bug libgcj/21065] javax.swing.event.EventListenerList.getListenerList() implemented wrong

[rmathew at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|java                        |libgcj


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21065

[Bug SWING/21065] javax.swing.event.EventListenerList.getListenerList() implemented wrong

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|libgcj                      |SWING


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21065

[Bug SWING/21065] javax.swing.event.EventListenerList.getListenerList() implemented wrong

[roman at kennke dot org]

------- Additional Comments From roman at kennke dot org  2005-04-25 08:57 -------
I have tested this against the current GNU Classpath code. At least there it
works correctly. I suppose the EventListenerList from GNU Classpath has to be
merged into GCJ, if it isn't done yet (I haven't checked GCJ).

/Roman

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21065

[Bug SWING/21065] javax.swing.event.EventListenerList.getListenerList() implemented wrong

[konqueror at gmx dot de]

------- Additional Comments From konqueror at gmx dot de  2005-04-25 09:50 -------
As you can see at
http://developer.classpath.org/compare/classpath-libgcj/libgcj-classpath-compare.html
this class is merged. This page is updated twice a day so pretty uptodate normally.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21065

[Bug SWING/21065] javax.swing.event.EventListenerList.getListenerList() implemented wrong

[tromey at gcc dot gnu dot org]

------- Additional Comments From tromey at gcc dot gnu dot org  2005-04-26 20:23 -------
This works for me with 4.0 and cvs trunk.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21065