The ContainerEvent has the constructor:
    public ContainerEvent(Component source, int id, Component child) 
should instead have:
    public ContainerEvent(Container source, int id, Component child) 

The getContainer() method will fail if the source is not a container
(comment in this method says that cast is always OK. It isn't.)

---- The ContainerEvent's source ----
    /**
     * Constructs a ContainerEvent object.
     * 
     * @param source the Component object (container) that originated the event
     * @param id     an integer indicating the type of event
     * @param child  the component that was added or removed
     */
    public ContainerEvent(Component source, int id, Component child) {
        super(source, id);
        this.child = child;
    }

    /**
     * Returns the originator of the event.
     *
     * @return the Container object that originated the event
     */
    public Container getContainer() {
        return (Container)source; // cast should always be OK, type was checked in constructor
    }

---- Here is the test (CE.java) ----
import java.awt.Button;
import java.awt.Container;
import java.awt.event.ContainerEvent;

public class CE {
public static void main(String[] args) {
  Button b=new Button("label");
  ContainerEvent ce=new ContainerEvent(b,ContainerEvent.COMPONENT_ADDED,b);
  Container c=ce.getContainer();
  System.exit(0); //will not exit under 1.2 without this line
}
}
---- output from the test ----
% java CE
java.lang.ClassCastException: java.awt.Button
	at java.awt.event.ContainerEvent.getContainer(ContainerEvent.java:86)
	at CE.main(CE.java:9)
-----------

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N/A

Mohamed Sulthan ( xxxxx@xxxxx )		March 30th 1999

Bug is reproducible in both Win32 and Solaris
( Tested with JDK  1.2fcs-I ).

Result:
---------
java.lang.ClassCastException: java.awt.Button
	at java.awt.event.ContainerEvent.getContainer(ContainerEvent.java:102)
	at CE.main(CE.java:14)
Exception in thread "main" Process completed with exit code 1

-------------------------------------------------

I commented the following line from the submitter code,

      // System.exit(0);

the  program is  exits with  above  Exception.
	

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5/21/2000  xxxxx@xxxxx  -- still true as of 1.1.8_003 and 1.3.0-C.

The ideal fix would be to add a more appropriate constructor (which
takes a Container instead of a Component) and to document the current
constructor as being kept around only for backward compatibility.
This would have to be done in 1.5.
 xxxxx@xxxxx  2002-07-23




It is almost impossible to mark old ctor as deprecated.  
So, we should just add check in getContainer() method.

 xxxxx@xxxxx  2003-04-22

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