@Test
public void testOverrideHeartbeatServers() {

  FlumeConfiguration cfg = new TestableConfiguration();
  cfg.set(FlumeConfiguration.MASTER_HEARTBEAT_SERVERS,
      "hostA:57891,hostB:57895,hostC:57893");
  cfg.setInt(FlumeConfiguration.MASTER_SERVER_ID, 1);
  assertEquals(57895, cfg.getMasterHeartbeatPort());
  // try with spaces
  cfg.set(FlumeConfiguration.MASTER_HEARTBEAT_SERVERS,
      "hostA : 57891 ,    hostB: 57895,   hostC:57893");
  assertEquals(57895, cfg.getMasterHeartbeatPort());
}