@Override
    public void nodeDataChanged(String path) {
      if (path.equals(node)) {
        LOG.debug("nodeDataChanged(" + path + ")");
        changedLock.release();
      }
    }
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