* the number of entries in the map, as that makes it easy for hostile inputs to trigger lots of
     * allocation—not that any program should be deserializing hostile inputs to begin with!)
     */
    setDelegates(new EnumMap<K, V>(keyTypeOrObjectUnderJ2cl), new HashMap<V, K>());
    Serialization.populateMap(this, stream);
  }

  @GwtIncompatible // only needed in emulated source.

  /** Creates a new, empty {@link ExecutionList}. */
  public ExecutionList() {}

  /**
   * Adds the {@code Runnable} and accompanying {@code Executor} to the list of listeners to
   * execute. If execution has already begun, the listener is executed immediately.
   *
   * <p>When selecting an executor, note that {@code directExecutor} is dangerous in some cases. See

    @Override
    protected void implCloseChannel() {
      throw new RuntimeException("I bet you didn't think Thread.interrupt could throw");
    }

    void doBegin() {
      super.begin();
    }
  }

  /**
   * Because Thread.interrupt() can invoke arbitrary code, it can be slow (e.g. perform IO). To
   * protect ourselves from that we want to make sure that tasks don't spin too much waiting for the

     * the number of entries in the map, as that makes it easy for hostile inputs to trigger lots of
     * allocation—not that any program should be deserializing hostile inputs to begin with!)
     */
    setDelegates(new EnumMap<K, V>(keyTypeOrObjectUnderJ2cl), new HashMap<V, K>());
    Serialization.populateMap(this, stream);
  }

  @GwtIncompatible // only needed in emulated source.

    @Override
    protected void implCloseChannel() {
      throw new RuntimeException("I bet you didn't think Thread.interrupt could throw");
    }

    void doBegin() {
      super.begin();
    }
  }

  /**
   * Because Thread.interrupt() can invoke arbitrary code, it can be slow (e.g. perform IO). To
   * protect ourselves from that we want to make sure that tasks don't spin too much waiting for the