@Test
public void testDuplicateAddExecutor() throws Exception {

  final String host = "localhost";
  final int port = 12345;
  this.executorDao.addExecutor(host, port);
  assertThatThrownBy(() -> this.executorDao.addExecutor(host, port))
      .isInstanceOf(ExecutorManagerException.class)
      .hasMessageContaining("already exist");
}