java - 在Java中将本地对象传递给线程不好的样式？

我发现我经常做以下事情。复制对象以发送到线程。线程是唯一使用过该对象的线程，并且我们具有事前发生的关系，因此它是线程安全的。

但这让我感到紧张。如评论所述，如果有人出现并用objForThread欺骗了该怎么办？
我应该使用锁吗？还是这是一种普遍接受的Java模式？

class Example
{
  private SomeObj mDynamicObj = new SomeObj();

  public void doWorkInAThread()
  {
    mutateThis(mDynamicObj);
    final SomeObj objForThread = new SomeObj(mDynamicObj);

    myExecutorService.submit(new Runnable() { @Override public void run()
    {
      doSomethingWith(objForThread);
    }});

    mutateThis(mDynamicObj);

    // Concerned that in the future someone will come
    // along and mutate objForThread here making this thread unsafe
  }
}

最佳答案

如果您感到紧张，则最好将引用传递给线程，而不要将其保持在本地：

class Example
{
    private SomeObj mDynamicObj = new SomeObj ();

    public void doWorkInAThread ()
    {
        class MyRunnable implements Runnable
        {
            private final SomeObj objForThread;

            public MyRunnable (SomeObj objForThread)
            {
                this.objForThread = objForThread;
            }

            @Override
            public void run ()
            {
                doSomethingWith (objForThread);
            }
        }

        mutateThis (mDynamicObj);

        myExecutorService.submit (new MyRunnable (new SomeObj (mDynamicObj)));

        mutateThis (mDynamicObj);
    }
}