问题的原因是
while(connected) {
String str=dis.readUTF();
System.out.println(str);
}
不断循环执行，一直在死循环获取socket发送的信息，
使得前面的语句
s = ss.accept();
connected=true;
服务端接收新的客户端不能再被执行
解决的方法——通过多线程技术
当获得一个socket后，则开启一个多线程，让
while(connected) {
String str=dis.readUTF();
System.out.println(str);
}
循环读取操作在多线程中完成
这样每个socket获得之后都在各自的现成中完成自己的循环读取
具体方法：
首先在主函数main中建立一个关于线程的内部类，因为这个类外部其他类不需要，所以弄成内部类
解决问题后效果图：
服务器端代码有较大改动，当中遇到各种异常逐一解决，逻辑思路上不复杂，细节上注意解决了
先开启客户端的各种异常
客户端关闭后的异常提示
服务端增加了ServerSocket的关闭
服务端增加线程处理后无效果的调试——根据socket closed异常查明是
在内部类Client中while循环写在了try的外边，导致socket已经被关闭，但循环依然在尽心，不断提示出错
0.7版的最终服务器端代码如下：
package com.swift; import java.io.DataInputStream;
import java.io.EOFException;
import java.io.IOException;
import java.net.BindException;
import java.net.ServerSocket;
import java.net.Socket; public class ChatServer { public static void main(String[] args) {
new ChatServer().fun();
} private void fun() {
boolean started = false;
ServerSocket ss = null;
Socket s = null;
try {
ss = new ServerSocket(8888);
started = true;
} catch (BindException e) {
System.out.println("端口使用中......");
} catch (IOException e1) {
e1.printStackTrace();
}
try {
while (started) {
s = ss.accept();
System.out.println("a client connected success");
Client c = new Client(s);
new Thread(c).start();
}
} catch (EOFException e) {
System.out.println("client has closed.");
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
ss.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
} class Client implements Runnable { private Socket s;
private DataInputStream dis;
private boolean connected = false; public Client(Socket s) {
this.s = s;
try {
this.dis = new DataInputStream(s.getInputStream());
connected = true;
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} @Override
public void run() {
try {//注意:要包括while循环，如果try在while循环里，则出现socket closed异常
while (connected) {
String str = dis.readUTF();
System.out.println(str);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (dis != null) {
try {
dis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (s != null) {
try {
s.close();
} catch (IOException e) {
e.printStackTrace();
}
}
} } }
}
0.7版本的客户端代码改动不大，代码如下：
package com.swift; import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ConnectException;
import java.net.Socket;
import java.net.UnknownHostException; import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField; public class ChatClientFrame extends JFrame { private static final long serialVersionUID = -118470059355655240L;
Socket s = null;
DataOutputStream dos = null;
JLabel label_shang = new JLabel();
JLabel label_xia = new JLabel();
JTextField tf = new JTextField(38);
JTextArea ta = new JTextArea(15, 50);
JButton button = new JButton(); public ChatClientFrame() {
setBounds(200, 200, 500, 400);
setTitle("客户端聊天工具 —— 0.7");
// 对窗口进行大的布局，分为三行一列，在pBasic面板上添加三个面板shang zhong xia
JPanel pBasic = new JPanel();
pBasic.setLayout(new BorderLayout());// 不设置默认也是这种布局模式
setContentPane(pBasic);// 把面板放在窗口上，不记得用this.关键字
JPanel shang = new JPanel();
JPanel zhong = new JPanel();
JPanel xia = new JPanel();
// 设置JPanel面板的大小
shang.setSize(470, 25);
zhong.setSize(470, 180);
xia.setSize(470, 40);
pBasic.add(shang, BorderLayout.NORTH);
pBasic.add(zhong, BorderLayout.CENTER);
pBasic.add(xia, BorderLayout.SOUTH);
shang.setBackground(Color.red);
zhong.setBackground(Color.yellow);
xia.setBackground(Color.blue); label_shang.setText("聊天记录");
shang.add(label_shang);
ta.setLineWrap(true);// 自动换行
JScrollPane scroll = new JScrollPane(ta);// 增加滚动条，以便不增加行数
zhong.add(scroll);
label_xia.setText("输入信息");
xia.add(label_xia, BorderLayout.WEST);
/*
* 增加功能，窗口监听事件，窗口打开时设置光标焦点在tf文本域中
*/
this.addWindowListener(new WindowAdapter() {
@Override
public void windowOpened(WindowEvent e) {
tf.requestFocus();
}
});
xia.add(tf, BorderLayout.CENTER);
button.setText("发送");
xia.add(button, BorderLayout.EAST); final class ShareListener implements ActionListener { @Override
public void actionPerformed(ActionEvent e) {
String taText = ta.getText();
String tfText = tf.getText() + "\r\n";
String tfText1 = tf.getText();
ta.setText(taText + tfText);
tf.setText("");
// 当回车或发送按钮时，tfText发送到服务器
try {
dos.writeUTF(tfText1);
dos.flush();
} catch (IOException e1) {
e1.printStackTrace();
} }
}
button.addActionListener(new ShareListener());
tf.addActionListener(new ShareListener());
// 通过压缩自动调整各个面板
pack();
this.addWindowListener(new WindowAdapter() {
@Override
public void windowClosing(WindowEvent e) {
disconnect();
System.exit(0);
}
});
setVisible(true);
// 创建窗体直接调用连接服务器
connect();
} public void connect() {
try {
s = new Socket("127.0.0.1", 8888);
System.out.println("connected!");
dos = new DataOutputStream(s.getOutputStream()); } catch (ConnectException e) {
System.out.println("服务端异常.........");
System.out.println("请确认服务端是否开启.........");
} catch (IOException e) {
e.printStackTrace();
}
} public void disconnect() {
try {
if (dos != null)
dos.close();
if (s != null)
s.close();
} catch (IOException e) {
e.printStackTrace();
}
} public static void main(String[] args) {
new ChatClientFrame();
} }