RCP中使用IWorkspaceRunnable解决IResourceChangeListener监听触发多次问题

IWorkspaceRunnable operation = new IWorkspaceRunnable() {
      public void run(IProgressMonitor monitor) throws CoreException {
            listener = new IResourceChangeListener() {
            public void resourceChanged(IResourceChangeEvent event) {    

 

                  Display.getDefault().asyncExec(new Runnable() {
                       public void run() {
                             // 你要执行的代码 - _ -           

                       }                

                  });
            }
            };
  
     }
};
try {
    workspace.run(operation, null);
    workspace.addResourceChangeListener(listener);
} catch (CoreException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}