Bug 17292 Inconsistent Undo behaviour for Cut/Copy/Paste in outline
Build 20020521 (freeze 1) 1) Open a java editor on some class 2) In the content outline, select a method and do Ctrl+X to cut 3) Notice in the menus, Edit->Undo and Refactor->Undo are disabled 4) Now select the type node in the content outline, and Ctrl+V to paste 5) Still, neither Undo action is enabled 6) Now click inside the editor area to give it focus. 7) Now "Edit->Undo" is possible. So, the problems are: 1) Undo is not consistent, it's available for Paste but not Cut. 2) Even when undo is possible, it only becomes enabled when the editor is activated.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaOutlinePage.java
ViewerFilter[] filters= getFilters();
					for (int i= 0; i < filters.length; i++) {
						result= filters[i].filter(this, parent, result);
						if (result.length == 0)
							return true;
					}
					
					return false;
				}
				
				protected void update(Widget w, IJavaElementDelta delta) {
					
					Item item;
					
					IJavaElement parent= delta.getElement();
					IJavaElementDelta[] affected= delta.getAffectedChildren();
					Item[] children= getChildren(w);
					boolean doUpdateParent= false;
										
					Vector deletions= new Vector();
					Vector additions= new Vector();				
					for (int i= 0; i < affected.length; i++) {
					    IJavaElementDelta affectedDelta= affected[i];
						IJavaElement affectedElement= affectedDelta.getElement();
						int status= affected[i].getKind();
						
						int j;
						for (j= 0; j < children.length; j++)
						    if (affectedElement.equals(children[j].getData()))
						    	break;