code: public static Runnable apply(final Runnable command, final EventExecutor eventExecutor) {
          ObjectUtil.checkNotNull(command, "command");
          ObjectUtil.checkNotNull(eventExecutor, "eventExecutor");
          return new Runnable() {
              @Override
              public void run() {
                  setCurrentEventExecutor(eventExecutor);
                  try {
                      command.run();
                  } finally {
                      setCurrentEventExecutor(null);
                  }
              }
          };
      }
docs: Decorate the given {@link Runnable} and ensure {@link #currentExecutor()} will return {@code eventExecutor}
  when called from within the {@link Runnable} during execution.