@Override
  public List<T> getChildren(String s, List<Stat> list, int i, int i1, int i2) throws HelixException {
    throw new IllegalStateException("Not implemented");
  }
{@inheritDoc}

This is not thread safe if some thread is setting {@link #readLatch}.
ambry-clustermap/src/test/java/com/github/ambry/clustermap/MockHelixPropertyStore.java