Someone

public void update(){
		((MMenuBar) this.getJMenuBar()).updateMenu();
		if(engine.inModelOpenState()){
			System.out.println("Open");
			JPanel contentPane = new JPanel(new BorderLayout());
			if(workspace==null){
				workspace = new MWorkspacePanel();
				contentPane.add(workspace, BorderLayout.CENTER);
			}
			if(loggerPanel==null){
				loggerPanel = new LoggerPanel();
				contentPane.add(loggerPanel, BorderLayout.SOUTH);
			}
			if(treePanel==null){
				treePanel = new MTreePanel();
				eastPanel = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
		        eastPanel.add(treePanel);
		        contentPane.add(eastPanel, BorderLayout.EAST);
			}
			contentPane.setOpaque(true);
			this.setContentPane(contentPane);
			contentPane.repaint();
		}else{//inModelClosedState
			System.out.println("Closed");
			workspace = null;
			loggerPanel = null;
			shapesbar = null;
			treePanel = null;
			eastPanel = null;
			propertyEditor = null;
			//this.getContentPane().removeAll();
			//this.getContentPane().repaint();
		}
	}