/**	 * 处理Ctrl+z ctrl+y 撤销重做事件	 * @param event	 * @author lldy 2013-6-20	 */	private void handleCtrlZYEvent(Event event){		if((event.keyCode & SWT.KEYCODE_BIT) == 0 && event.character != 0){			boolean ctrlDown = (event.stateMask & SWT.CTRL) != 0;    		boolean altDown = (event.stateMask & SWT.ALT) != 0;    		    		if (ctrlDown && !altDown){  			    			 switch(event.keyCode){    			 	case 'z'://撤销    			 		if(editor.getUndoManager().canUndo()){    			 			    			 			undoAction.run();    			 		}    		    		break;    		    	case 'y'://重做    		    		if(editor.getUndoManager().canRedo()){    			 			    			 			redoAction.run();    			 		}    		    		break;    		    	default:break;    			 }    		}		}	}