FULL PRODUCT VERSION :
java version "1.7.0_03"
Java(TM) SE Runtime Environment (build 1.7.0_03-b05)
Java HotSpot(TM) Client VM (build 22.1-b02, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7600]

A DESCRIPTION OF THE PROBLEM :
Under Java7 there's a regression in PropertyChangeSupport.addPropertyChangeListener(String, PropertyChangeListener) whereby a ClassCastException is thrown when the specified listener extends EventListenerProxy<T> and T does not extend PropertyChangeListener.

It appears to be due to PropertyChangeSupport.PropertyChangeListenerMap wrongly assuming that all wrapped EventListenerProxy<?> listeners are EventListenerProxy<PropertyChangeListener>. The unwrapping in PropertyChangeListenerMap.extract should be restricted to PropertyChangeListenerProxys.

REGRESSION. Last worked in version 6u29

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run the attached test case.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Test case completing successfully.
ACTUAL -
The attached exception is thrown.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Exception in thread "main" java.lang.ClassCastException: Main$MyListener cannot be cast to java.beans.PropertyChangeListener
at java.beans.PropertyChangeSupport.addPropertyChangeListener(PropertyChangeSupport.java:201)
at Main.main(Main.java:36)


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.util.EventListener;
import java.util.EventListenerProxy;

public class Main
{
public static class MyListener implements EventListener
{
}

public static class MyProxyListener extends EventListenerProxy<MyListener> implements PropertyChangeListener
{
public MyProxyListener(MyListener proxy)
{
super(proxy);
}

@Override
public void propertyChange(PropertyChangeEvent event)
{
}
}

public static void main(String[] args)
{
MyListener listener = new MyListener();
PropertyChangeListener proxyListener = new MyProxyListener(listener);
PropertyChangeSupport support = new PropertyChangeSupport(new Main());

// OK
support.addPropertyChangeListener(proxyListener);

// throws ClassCastException in Java7
support.addPropertyChangeListener("foo", proxyListener);
}
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Introduce EventListenerProxy2 as a copy of EventListenerProxy and extend that instead for added property change listeners, if possible.