Question

我尝试从客户端向服务器发送一个int值。这是我在下面使用的客户端代码：

_port   = 8071;
_socket = new Socket("localhost", _port);

Random rand = new Random();
int  n = rand.nextInt(50) + 1;
DataOutputStream dos = new DataOutputStream(_socket.getOutputStream());
dos.writeInt(n);
dos.flush();

服务器代码

try {
    input = new BufferedReader(new InputStreamReader(socket.getInputStream()));

    ObjectInputStream in = null;
    in = new ObjectInputStream(socket.getInputStream());
    int ClientNumber= in.readInt();
    System.out.println(ClientNumber);
}

但是我收到了无效的流标头错误。

无效的流标题：0000002B at java.io.ObjectInputStream.readStreamHeader（ObjectInputStream.java:781）在java.io.ObjectInputStream。（ObjectInputStream.java:278）at ServiceRequest.run（ServiceRequest.java:24）at java.util.concurrent.Executors $ RunnableAdapter.call（Executors.java:439） at java.util.concurrent.FutureTask $ Sync.innerRun（FutureTask.java:303）在java.util.concurrent.FutureTask.run（FutureTask.java:138）at java.util.concurrent.ThreadPoolExecutor中的$ Worker.runTask（ThreadPoolExecutor.java:895）在 java.util.concurrent.ThreadPoolExecutor中的$ Worker.run（ThreadPoolExecutor.java:918）在java.lang.Thread.run（Thread.java:680）

有谁知道导致错误的原因是什么？我的代码设置不正确吗？

Answer 1

您使用DataOutputStream使用ObjectInputStream和阅读撰写。您应该使用DataInputStream代替：

// Note declaration and assignment in a single statement. There's no point in
// making it null first.
DataInputStream in = new DataInputStream(socket.getInputStream());

// Note use of camelCase for variable name
int clientNumber = in.readInt();

你也应该在这里摆脱input：你不是在读它，因为这看起来像是二进制数据的流，所以将它当作文本处理是不合适的

哦，你应该在finally块中关闭输入流。

Answer 2

尝试像这样改变它

try {
             //   input = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            DataInputStream in = new DataInputStream(socket.getInputStream());
            int clientNumber= in.readInt();
            System.out.println(clientNumber);
}

它应该有用。 ObjectInputStream只能读取ObjectOuputStream发送的流，它以幻数（标题）0xACED开头，见http://docs.oracle.com/javase/6/docs/platform/serialization/spec/protocol.html

将InputStreamReader与Java一起使用时出错

2 个答案: