Name: sdR10048 Date: 08/15/2003


Filed By : SPB JCK team (###@###.###)
JDK : java full version "1.5.0-beta-b13"

Specification excerpt:
======================
--------- J2SE API spec v.1.5 ---------
...
public void dragEnter(DropTargetDragEvent dtde)
  Calls dragEnter on the registered DropTargetListener and passes it the specified
  DropTargetDragEvent. Has no effect if this DropTarget is not active.

Parameters:
  dtde - the DropTargetDragEvent
Throws:
  NullPointerException - if this DropTarget is active and dtde is null

...
---------- end-of-excerpt ---------------

Problem description
===================
Currently spec does not describe will DropTarget notify the registered listener
in case if this DropTarget is active and 'dtde' is null.

JDK 1.5.0 b13 does notify the listener with a null event.

The same issue with some other methods as well:

dragExit
dragOver
drop
dropActionChanged

    
Minimized test:
===============
------- T.java -------
import java.awt.dnd.*;

public class T implements DropTargetListener {

    private String method = null;

    public String getMethod() {
        return method;
    }

    public void dragEnter(DropTargetDragEvent dsde) {method = "dragEnter";}

    public void dragOver(DropTargetDragEvent dsde) {method = "dragOver";}

    public void dropActionChanged(DropTargetDragEvent dsde) {method = "dropActionChanged";}

    public void dragExit(DropTargetEvent dsde) {method = "dragExit";}

    public void drop(DropTargetDropEvent dsde) {method = "drop";}

    public T() {
    }

    public static void main(String[] args) {
        DropTarget dt = new DropTarget();
        T t = new T();
        try {
            dt.addDropTargetListener(t);
        } catch (Exception e) {
            e.printStackTrace();
        }
        dt.setActive(true);
        System.out.println("t.getMethod(): "+t.getMethod());
        try {
            dt.dragEnter(null);
        } catch (NullPointerException e) {
            System.out.println("NPE: "+e);
        }
        System.out.println("t.getMethod(): "+t.getMethod());
    }
}

------- end-of-T.java -------

Minimized test output:
======================
t.getMethod(): null
NPE: java.lang.NullPointerException
t.getMethod(): dragEnter

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