Method runCallbacks

src/Deferred.java:1231–1268

Executes all the callbacks in the current chain.

()

   * Executes all the callbacks in the current chain.
   */
  private void runCallbacks() {
    while (true) {
      Callback cb = null;
      Callback eb = null;
      synchronized (this) {
        // Read those into local variables so we can call doCall and invoke the
        // callbacks without holding the lock on `this', which would cause a
        // deadlock if we try to addCallbacks to `this' while a callback is
        // running.
        if (callbacks != null && next_callback != last_callback) {
          cb = callbacks[next_callback++];
          eb = callbacks[next_callback++];
        }
        // Also, we may need to atomically change the state to DONE.
        // Otherwise if another thread is blocked in addCallbacks right before
        // we're done processing the last element, we'd enter state DONE and
        // leave this method, and then addCallbacks would add callbacks that
        // would never get called.
        else {
          state = DONE;
          callbacks = null;
          next_callback = last_callback = 0;
          break;
        }
      }

      //final long start = System.nanoTime();
      //LOG.debug("START >>>>>>>>>>>>>>>>>> doCall(" + cb + ", " + eb + ')');
      if (doCall(result instanceof Exception ? eb : cb)) {
        //LOG.debug("PAUSE ================== doCall(" + cb + ", " + eb
        //          + ") in " + (System.nanoTime() - start) / 1000 + "us");
        break;
      }
      //LOG.debug("DONE  <<<<<<<<<<<<<<<<<< doCall(" + cb + ", " + eb
      //          + "), result=" + result
      //          + " in " + (System.nanoTime() - start) / 1000 + "us");
    }
  }

  /**
   * Executes a single callback, handling continuation if it returns a Deferred.