private List<ReplicationLoadSource> waitOnMetricsReport(int greaterThan, ServerName serverName)
    throws Exception {
    UTIL1.waitFor(30000, 1000, new Waiter.ExplainingPredicate<Exception>() {
      @Override
      public boolean evaluate() throws Exception {
        List<ReplicationLoadSource> list =
          hbaseAdmin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS)).getLiveServerMetrics()
            .get(serverName).getReplicationLoadSourceList();
        return list.size() > greaterThan;
      }

      @Override
      public String explainFailure() throws Exception {
        return "The ReplicationLoadSourceList's size is lesser than or equal to " + greaterThan
          + " for " + serverName;
      }
    });

    return hbaseAdmin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS)).getLiveServerMetrics()
      .get(serverName).getReplicationLoadSourceList();
  }
Wait until Master shows metrics counts for ReplicationLoadSourceList that are greater than
<code>greaterThan</code> for <code>serverName</code> before returning. We want to avoid case
where RS hasn't yet updated Master before allowing test proceed.
@param greaterThan size of replicationLoadSourceList must be greater before we proceed
hbase-server/src/test/java/org/apache/hadoop/hbase/replication/TestReplicationStatus.java