socket 通信基本类（invalid type code: AC和BlockDataInputStream.peekByte异常） -

jacky1118sally

浏览: 13868 次
性别:

最近访客更多访客>>

s1102060857

博主相关

博客

微博

相册

留言

关于我

文章分类

社区版块

存档分类

socket 通信基本类（invalid type code: AC和BlockDataInputStream.peekByte异常）

博客分类：

J2SE

thread Socket peekByte invalid type

由于需要做个一个CS的系统，需要实现服务器和客户端的交互，那么这个通讯的基本类就很重要了为了写这个基本类真是费了一番周折。要把这个做好多线程需要理解的比较好。因为服务器需要一直监听客户端的请求，而客户端也要一直监听服务器的请求。

首先是客户端：

package client;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;
import java.net.UnknownHostException;
public class Client implements Runnable{
private Socket client;
private String ip = "127.0.0.1";
private int port = 8888;
private ObjectOutputStream out;

//连接
public void conn(){
         try {

     client = new Socket(ip,port);

     if(client.getOutputStream()!=null) {

      out = new ObjectOutputStream(client.getOutputStream());

     }


    } catch (UnknownHostException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
    } catch (IOException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
    }
        }

        //启动线程
public void run() {
   try {
ObjectInputStream in = new ObjectInputStream(client.getInputStream());

       boolean flag = true;
    while(flag){
     Object obj = in.readObject();
     if(obj!=null){
      String s = (String)obj;
      System.out.println("收到服务器消息：" + s);
      if(s.equals("shutdown")){
       flag = false;
      }
     }
    }
    System.out.println("ByeBye!");
   } catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   } catch (ClassNotFoundException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
}

//向服务器发送object
public void sendMessage(Object obj){
   //ObjectOutputStream out=null;
   try {

            out.writeObject(obj);
            out.flush();

   } catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }

}

}

服务器端有两个类：

主类：

package server;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
public class MainServer implements Runnable{
private int port = 8888;
List arr = new ArrayList();

//初始化方法
public void init(int port) {
   this.port = port;
}

public void run() {
   try {

    ServerSocket server = new ServerSocket(port);
    System.out.println("--------服务器启动---------");
    while (true) {
     Socket socket = server.accept();
     System.out.println("--------客户端连接---------");

     String ip = socket.getLocalSocketAddress()+"";
     ip = ip.substring(1,10);

     ServerAccept acc = new ServerAccept();
     acc.init(socket,ip);
     arr.add(acc);//将客户端放入数组中
     acc.start();


    }
   } catch (Exception e) {

    e.printStackTrace();
   }
}

//遍历数组，对指定IP发送object
public void sendMessage(String ip,Object obj) {

for(int i=0;i<arr.size();i++) {
   ServerAccept a = (ServerAccept)arr.get(i);
   String temp = a.getIp();
   if(temp.equals(ip)) {
    try {
     a.getOut().writeObject(obj);
     a.getOut().flush();
    } catch (IOException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();

    }
   }

}

}

}

线程类：

package server;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;

public class ServerAccept extends Thread {

//private ObjectInputStream in;
private ObjectOutputStream out;
private String ip;
private String s;
private Socket socket;

    public void init(Socket socket,String ip) {

   try {
    this.socket=socket;
    this.out = new ObjectOutputStream(socket.getOutputStream());
    this.ip=ip;
   } catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
}



//一直监听客户端发送到来的消息
public void run() {

   boolean flag = true;
   try {

    ObjectInputStream in = new ObjectInputStream(socket.getInputStream());
        while(flag){

      Object obj = in.readObject();

      if(obj!=null){
       String s = (String)obj;
       if(s.equals("关闭")){

        flag = false;
        continue;
       }
       System.out.println("客户端消息：" + s);
      }



     }


    // System.out.println("ByeBye!");

   } catch (IOException e) {
    // TODO Auto-generated catch block
    flag = false;
    e.printStackTrace();
   } catch (ClassNotFoundException e) {
    // TODO Auto-generated catch block
    flag = false;
    e.printStackTrace();
   }

   }

public String getIp() {
   return ip;
}

public ObjectOutputStream getOut() {
   return out;
}

public String getS() {
   return s;
}

}

在这个过程中主要遇到了最令人头疼的 java.io.StreamCorruptedException: invalid type code: AC 异常。

一直不明白怎么回事后来才知道原来是 ObjectOutputStream 流只可以对应，不可以生成多次，

当时我把红色的那一段代码放在了 while 里面结果一直报错，只可以发送一次，第二次就不行，因为你又new 了一个 ObjectOutputStream 那是不可以的同一个 socket。

还有一个异常就是 java.io.ObjectInputStream$BlockDataInputStream.peekByte 异常

这个意思我查阅了一下原来是到达了文件的末尾，程序却没有正常结束读取文件内容也就是蓝色的这一段会抛异常因为无法终止while 。后来我要结束流的时候就发送消息“关闭” 然后就关闭了。socket是面向连接的所以终止任何一方都会异常吧，现在都是捕获到异常然后关闭呵呵呵。不过应该有好的方法。我毕竟写的很多缺陷了。

这个基本类实现了监听，主要就是在于线程中的连个while 循环在一直等待着对方的消息，也是这里不好处理。

希望大家提出意见改进啊

测试类：

package client;

public class ClientTest {

public static void main(String []args) {

   Client client = new Client();

     client.conn();

   new Thread(client).start();

   client.sendMessage("我发送的消息！");
   client.sendMessage("这也是我发送的消息！");
   client.sendMessage("关闭");

}

     服务器：

/*
* ServerForm.java
*
* Created on __DATE__, __TIME__
*/

package server;

import java.util.HashMap;

/**
*
* @author __USER__
*/
public class ServerForm extends javax.swing.JFrame {

/** Creates new form ServerForm */
public ServerForm() {
   initComponents();
}

/*
* 创建server对象
*
*/
MainServer server = new MainServer();

//ServerTest ser = new ServerTest();

/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
*/

//GEN-BEGIN:initComponents
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {

   jButton1 = new javax.swing.JButton();
   jTextField1 = new javax.swing.JTextField();
   jButton2 = new javax.swing.JButton();

   setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

   jButton1.setText("\u542f\u52a8\u670d\u52a1\u5668");
   jButton1.addActionListener(new java.awt.event.ActionListener() {
    public void actionPerformed(java.awt.event.ActionEvent evt) {
     jButton1ActionPerformed(evt);
    }
   });

   jButton2.setText("\u53d1\u9001\u6d88\u606f");
   jButton2.addActionListener(new java.awt.event.ActionListener() {
    public void actionPerformed(java.awt.event.ActionEvent evt) {
     jButton2ActionPerformed(evt);
    }
   });

   javax.swing.GroupLayout layout = new javax.swing.GroupLayout(
     getContentPane());
   getContentPane().setLayout(layout);
   layout
     .setHorizontalGroup(layout
       .createParallelGroup(
         javax.swing.GroupLayout.Alignment.LEADING)
       .addGroup(
         javax.swing.GroupLayout.Alignment.TRAILING,
         layout
           .createSequentialGroup()
           .addContainerGap(47, Short.MAX_VALUE)
           .addGroup(
             layout
               .createParallelGroup(
                 javax.swing.GroupLayout.Alignment.LEADING)
               .addComponent(jButton1)
               .addGroup(
                 layout
                   .createSequentialGroup()
                   .addComponent(
                     jTextField1,
                     javax.swing.GroupLayout.PREFERRED_SIZE,
                     139,
                     javax.swing.GroupLayout.PREFERRED_SIZE)
                   .addGap(
                     18,
                     18,
                     18)
                   .addComponent(
                     jButton2)))
           .addContainerGap()));
   layout
     .setVerticalGroup(layout
       .createParallelGroup(
         javax.swing.GroupLayout.Alignment.LEADING)
       .addGroup(
         javax.swing.GroupLayout.Alignment.TRAILING,
         layout
           .createSequentialGroup()
           .addContainerGap(76, Short.MAX_VALUE)
           .addComponent(jButton1)
           .addGap(70, 70, 70)
           .addGroup(
             layout
               .createParallelGroup(
                 javax.swing.GroupLayout.Alignment.BASELINE)
               .addComponent(jButton2)
               .addComponent(
                 jTextField1,
                 javax.swing.GroupLayout.PREFERRED_SIZE,
                 javax.swing.GroupLayout.DEFAULT_SIZE,
                 javax.swing.GroupLayout.PREFERRED_SIZE))
           .addGap(104, 104, 104)));

   pack();
}// </editor-fold>
//GEN-END:initComponents

private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {

   String s = jTextField1.getText();
   server.sendMessage("127.0.0.1", s);
   jTextField1.setText("");
}

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {

   new Thread(server).start();

}

/**
* @param args the command line arguments
*/
public static void main(String args[]) {

   java.awt.EventQueue.invokeLater(new Runnable() {
    public void run() {
     new ServerForm().setVisible(true);
    }
   });

}

//GEN-BEGIN:variables
// Variables declaration - do not modify
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JTextField jTextField1;
// End of variables declaration//GEN-END:variables

}

说明：

1，运行serverForm，点击启动服务器。
2，运行clientTest，启动一个客户端。
3，在form界面，输入字符串，点击发送，会发送给服务器，在控制台输出。

由于我用的是 MyEclipse 8.0 这个界面是生成的如果版本低的话可能要导架包哈呵呵

分享到：