@Override
    public void run() {
      LOG.info("Waiting for data to be available in WaitToGetDataThread");
      try {
        tracker.blockUntilAvailable();
      } catch (InterruptedException e) {
        e.printStackTrace();
      }
      LOG.info("Data now available in tracker from WaitToGetDataThread");
      hasData = true;
    }
Test that we can interrupt a node that is blocked on a wait.
hbase-zookeeper/src/test/java/org/apache/hadoop/hbase/zookeeper/TestZKNodeTracker.java