private void startThreadsAndWaitToJoin(Thread[] threads) throws InterruptedException {
    for (int i = 1; i <= nthreads; i++) {
      threads[i - 1].start();
    }
    for (int i = 1; i <= nthreads; i++) {
      threads[i - 1].join();
    }
  }
Read the attributes from Hadoop->HBase->RegionServer->MetaTableMetrics in JMX
@throws IOException when fails to retrieve jmx metrics.
hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestMetaTableMetrics.java