public void join() {
    if (this.regionThreads != null) {
      for (Thread t : this.regionThreads) {
        if (t.isAlive()) {
          try {
            Threads.threadDumpingIsAlive(t);
          } catch (InterruptedException e) {
            LOG.debug("Interrupted", e);
          }
        }
      }
    }
    if (this.masterThreads != null) {
      for (Thread t : this.masterThreads) {
        if (t.isAlive()) {
          try {
            Threads.threadDumpingIsAlive(t);
          } catch (InterruptedException e) {
            LOG.debug("Interrupted", e);
          }
        }
      }
    }
  }
Wait for Mini HBase Cluster to shut down. Presumes you've already called {@link #shutdown()}.
hbase-server/src/main/java/org/apache/hadoop/hbase/LocalHBaseCluster.java