if(commentStart == null || commentEnd == null)
if(!textArea.isEditable() || commentStart == null || commentEnd == null)
	public void actionPerformed(ActionEvent evt)	{		View view = getView(evt);		JEditTextArea textArea = view.getTextArea();		Buffer buffer = view.getBuffer();		String commentStart = (String)buffer.getProperty("commentStart");		String commentEnd = (String)buffer.getProperty("commentEnd");		if(commentStart == null || commentEnd == null)		{			view.getToolkit().beep();			return;		}		buffer.beginCompoundEdit();		try		{			buffer.insertString(textArea.getSelectionStart(),				commentStart,null);			buffer.insertString(textArea.getSelectionEnd(),				commentEnd,null);			textArea.select(textArea.getCaretPosition(),				textArea.getCaretPosition());		}		catch(BadLocationException bl)		{			Log.log(Log.ERROR,this,bl);		}		finally		{			buffer.endCompoundEdit();		}	}