public List<JVMClusterUtil.MasterThread> getLiveMasters() {
    List<JVMClusterUtil.MasterThread> liveServers = new ArrayList<>();
    List<JVMClusterUtil.MasterThread> list = getMasters();
    for (JVMClusterUtil.MasterThread mt : list) {
      if (mt.isAlive()) {
        liveServers.add(mt);
      }
    }
    return liveServers;
  }
@return List of running master servers (Some servers may have been killed or aborted during
        lifetime of cluster; these servers are not included in this list).
hbase-server/src/main/java/org/apache/hadoop/hbase/LocalHBaseCluster.java