@Test
 public void dontFailWithoutParentForCheckListen() {
   int port = 234;
   managerWithoutOriginal.checkListen(port);
 }
 @Test
 public void delegateCheckListen() {
   int port = 234;
   managerWithOriginal.checkListen(port);
   verify(originalSecurityManager).checkListen(port);
 }