Method flush

src/RegionClient.java:389–413

Flushes to HBase any buffered client-side write operation. @return A Deferred, whose callback chain will be invoked when everything that was buffered at the time of the call has been flushed.

()

   * everything that was buffered at the time of the call has been flushed.
   */
  Deferred<Object> flush() {
    // Copy the batch to a local variable and null it out.
    final MultiAction batched_rpcs;
    final ArrayList<Deferred<Object>> pending;
    synchronized (this) {
      batched_rpcs = this.batched_rpcs;
      this.batched_rpcs = null;
      pending = getPendingRpcs();
    }

    if (pending != null && !pending.isEmpty()) {
      @SuppressWarnings("unchecked")
      final Deferred<Object> wait = (Deferred) Deferred.group(pending);
      // We can return here because if we found pending RPCs it's guaranteed
      // that batched_rpcs was null.
      return wait;
    }

    if (batched_rpcs == null || batched_rpcs.size() == 0) {
      return Deferred.fromResult(null);
    }
    final Deferred<Object> d = batched_rpcs.getDeferred();
    sendRpc(batched_rpcs);
    return d;
  }

  /**
   * Introduces a sync point for all outstanding RPCs.