final String key = "bar";

    // start computing thread
    new Thread() {
      @Override
      public void run() {
        result.set(0, cache.getUnchecked(key));
        doneSignal.countDown();
      }
    }.start();

    // wait for computation to start
    secondSignal.await();

    // start waiting thread
    new Thread() {
      @Override

                  if (!method.getDeclaringClass().equals(type)) {
                    return method.invoke(delegate, args);
                  }
                  checkState(started.getCount() == 1);
                  started.countDown();
                  try {
                    return method.invoke(delegate, args);
                  } catch (InvocationTargetException e) {
                    throw e.getCause();

                  if (!method.getDeclaringClass().equals(type)) {
                    return method.invoke(delegate, args);
                  }
                  checkState(started.getCount() == 1);
                  started.countDown();
                  try {
                    return method.invoke(delegate, args);
                  } catch (InvocationTargetException e) {
                    throw e.getCause();

    final String key = "bar";

    // start computing thread
    new Thread() {
      @Override
      public void run() {
        result.set(0, cache.getUnchecked(key));
        doneSignal.countDown();
      }
    }.start();

    // wait for computation to start
    secondSignal.await();

    // start waiting thread
    new Thread() {
      @Override