Method shutdown

src/RegionClient.java:479–566

Attempts to gracefully terminate the connection to this RegionServer.

()

   * Attempts to gracefully terminate the connection to this RegionServer.
   */
  public Deferred<Object> shutdown() {
    final class RetryShutdown<T> implements Callback<Deferred<Object>, T> {
      private final int nrpcs;
      RetryShutdown(final int nrpcs) {
        this.nrpcs = nrpcs;
      }
      public Deferred<Object> call(final T ignored) {
        return shutdown();
      }
      public String toString() {
        return "wait until " + nrpcs + " RPCs complete";
      }
    };

    // First, check whether we have RPCs in flight.  If we do, we need to wait
    // until they complete.
    {
      final ArrayList<Deferred<Object>> inflight = getInflightRpcs();
      final int size = inflight.size();
      if (size > 0) {
        return Deferred.group(inflight)
          .addCallbackDeferring(new RetryShutdown<ArrayList<Object>>(size));
      }
      // Then check whether have batched RPCs.  If we do, flush them.
      // Copy the batch to a local variable and null it out.
      final MultiAction batched_rpcs;
      synchronized (this) {
        batched_rpcs = this.batched_rpcs;
        this.batched_rpcs = null;
      }
      if (batched_rpcs != null && batched_rpcs.size() != 0) {
        final Deferred<Object> d = batched_rpcs.getDeferred();
        sendRpc(batched_rpcs);
        return d.addCallbackDeferring(new RetryShutdown<Object>(1));
      }
    }

    {
      final ArrayList<Deferred<Object>> pending = getPendingRpcs();
      if (pending != null) {
        return Deferred.group(pending).addCallbackDeferring(
          new RetryShutdown<ArrayList<Object>>(pending.size()));
      }
    }

    final Channel chancopy = chan;     // Make a copy as ...
    if (chancopy == null) {
      return Deferred.fromResult(null);
    }
    LOG.debug("Shutdown requested, chan={}", chancopy);
    if (chancopy.isConnected()) {
      Channels.disconnect(chancopy);   // ... this is going to set it to null.
      // At this point, all in-flight RPCs are going to be failed.
    }
    if (chancopy.isBound()) {
      Channels.unbind(chancopy);
    }
    // It's OK to call close() on a Channel if it's already closed.