我知道Java I / O使用装饰器模式。但是我觉得我理解它的错。

请说明两个代码段之间的区别：

片段1：

    PipedInputStream pipedInputStream = new PipedInputStream();
    PipedOutputStream pipedOutputStream = new PipedOutputStream();
    pipedOutputStream.connect(pipedInputStream);


    ObjectOutputStream objectOutputStream = new ObjectOutputStream(pipedOutputStream);

    objectOutputStream.writeObject("this is my string");

    ObjectInputStream objectInputStream = new ObjectInputStream(pipedInputStream);

    System.out.println(objectInputStream.readObject());

该应用程序符合我的期望，并且在控制台中看到结果。

片段2：

我尝试两次包装ObjectInputStream和ObjectOutputStream：

        PipedInputStream pipedInputStream = new PipedInputStream();
        PipedOutputStream pipedOutputStream = new PipedOutputStream();
        pipedOutputStream.connect(pipedInputStream);


        ObjectOutputStream objectOutputStream = new ObjectOutputStream(pipedOutputStream);
        ObjectOutputStream objectOutputStreamWrapper = new ObjectOutputStream(objectOutputStream);     //double wrapping

        objectOutputStreamWrapper.writeObject("this is my string");

        ObjectInputStream objectInputStream = new ObjectInputStream(pipedInputStream);
        ObjectInputStream   objectInputStreamWrapper = new ObjectInputStream(objectInputStream);

        System.out.println(objectInputStreamWrapper.readObject());

这段代码只是挂断了。我不明白为什么。请澄清。

聚苯乙烯

这仅仅是理论问题。

更新

真正的挂断行为是因为我使用管道而发生的（根据EJP回答）。

例如，此代码按预期工作。

            OutputStream outputStream = new FileOutputStream("2.txt");

            ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
            ObjectOutputStream objectOutputStreamWrapper = new ObjectOutputStream(objectOutputStream);     //double wrapping

            objectOutputStreamWrapper.writeObject("this is my string");
            objectOutputStream.close();

            ObjectInputStream objectInputStream = new ObjectInputStream(new FileInputStream("2.txt"));
            ObjectInputStream   objectInputStreamWrapper = new ObjectInputStream(objectInputStream);


            System.out.println(objectInputStreamWrapper.readObject());
            objectInputStream.close();

看起来如果我用10个装饰器包装输入，我应该用10个装饰器以相同顺序包装输出。是真的吗

更新+1

我注意到仅冲洗的问题：

PipedInputStream pipedInputStream = new PipedInputStream();
    PipedOutputStream pipedOutputStream = new PipedOutputStream();
    pipedOutputStream.connect(pipedInputStream);


    ObjectOutputStream objectOutputStream = new ObjectOutputStream(pipedOutputStream);
    ObjectOutputStream objectOutputStreamWrapper = new ObjectOutputStream(objectOutputStream);     //double wrapping

    objectOutputStreamWrapper.writeObject("this is my string");

    objectOutputStreamWrapper.flush();

    ObjectInputStream objectInputStream = new ObjectInputStream(pipedInputStream);
    ObjectInputStream   objectInputStreamWrapper = new ObjectInputStream(objectInputStream);

    System.out.println(objectInputStreamWrapper.readObject());