code: public void setWatches(long relativeZxid, List<String> dataWatches,
              List<String> existWatches, List<String> childWatches, Watcher watcher) {
          dataTree.setWatches(relativeZxid, dataWatches, existWatches, childWatches, watcher);
      }
docs: set watches on the datatree
  @param relativeZxid the relative zxid that client has seen
  @param dataWatches the data watches the client wants to reset
  @param existWatches the exists watches the client wants to reset
  @param childWatches the child watches the client wants to reset
  @param watcher the watcher function