Description hanshikun 2008-09-05 03:57:36 EDT

In some case when drag a shape with Ctrl key , I get a NullPointerException in DragEditPartsTrackerEx like:
java.lang.NullPointerException
	at org.eclipse.gmf.runtime.diagram.ui.tools.DragEditPartsTrackerEx.addSourceCommands(DragEditPartsTrackerEx.java:97)
	at org.eclipse.gmf.runtime.diagram.ui.tools.DragEditPartsTrackerEx.getCommand(DragEditPartsTrackerEx.java:62)
	at org.eclipse.gef.tools.DragEditPartsTracker.handleDragInProgress(DragEditPartsTracker.java:351)
	at org.eclipse.gmf.runtime.diagram.ui.tools.DragEditPartsTrackerEx.handleDragInProgress(DragEditPartsTrackerEx.java:178)
	at org.eclipse.gef.tools.AbstractTool.mouseDrag(AbstractTool.java:994)
	at org.eclipse.gef.tools.SelectionTool.mouseDrag(SelectionTool.java:511)
	at org.eclipse.gef.EditDomain.mouseDrag(EditDomain.java:230)
...

I check the source code of DragEditPartsTrackerEx.java and find that it maybe a miss in getCommand().
"if (getTargetEditPart()!=null)" is checked following the "addSourceCommands(false, command); " , but targetEditPart is also used in addSourceCommands() method.
In some case targetEditPart is null, NullPointerException is throwed.


	/**
	 * @see org.eclipse.gef.tools.AbstractTool#getCommand()
	 */
	protected Command getCommand() {
		if (!isMove()) {
			CompoundCommand command = new CompoundCommand();
****			addSourceCommands(false, command); 
****			if (getTargetEditPart()!=null){
				command.add(getTargetEditPart().getCommand(getTargetRequest()));
				if (command.canExecute())
					return command;
			} 
			
			
		}
		CompoundCommand command = new CompoundCommand();
		addSourceCommands(true, command);
		return command;
	}