private void children()

in twill-zookeeper/src/main/java/org/apache/twill/internal/zookeeper/RewatchOnExpireWatcher.java [128:172]

38 lines of code
7 McCabe index (conditional complexity)


  private void children() {
    Futures.addCallback(client.getChildren(path, this), new FutureCallback<NodeChildren>() {
      @Override
      public void onSuccess(NodeChildren result) {
        Object oldResult = lastResult.getReference();
        lastResult.compareAndSet(oldResult, null, true, false);

        if (result.equals(oldResult)) {
          return;
        }

        if (!(oldResult instanceof NodeChildren)) {
          // Something very wrong
          LOG.error("The same watcher has been used for different event type.");
          return;
        }

        NodeChildren oldNodeChildren = (NodeChildren) oldResult;
        if (!result.getChildren().equals(oldNodeChildren.getChildren())) {
          process(new WatchedEvent(Event.EventType.NodeChildrenChanged, Event.KeeperState.SyncConnected, path));
        } else {
          process(new WatchedEvent(Event.EventType.NodeDataChanged, Event.KeeperState.SyncConnected, path));
        }
      }

      @Override
      public void onFailure(Throwable t) {
        if (RetryUtils.canRetry(t)) {
          children();
          return;
        }

        lastResult.set(null, false);
        if (t instanceof KeeperException) {
          KeeperException.Code code = ((KeeperException) t).code();
          if (code == KeeperException.Code.NONODE) {
            // Node deleted
            process(new WatchedEvent(Event.EventType.NodeDeleted, Event.KeeperState.SyncConnected, path));
            return;
          }
        }
        LOG.error("Fail to re-set watch on getChildren for path " + path, t);
      }
    });
  }