java 网上聊天（发送方发送数据，接收方能够接到，反之亦然）

import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.*; import java.net.*; import javax.swing.*; public class Server extends JFrame implements ActionListener { private static final long serialVersionUID = 2987021233750012438L; JPanel p1 = new JPanel(); JPanel p2 = new JPanel(); JTextArea t1 = new JTextArea(); JTextField t2 = new JTextField(30); JButton b1 = new JButton("发送"); JButton bb = new JButton("启动服务器"); ServerSocket ssock; Accepter accepter; Waiter wait; public Server() { JScrollPane jj = new JScrollPane(t1); this.getContentPane().add(jj, "Center"); t1.setEditable(false);// 滚动面板不可编辑 p1.add(t2); p1.add(b1); p2.add(bb); t2.addActionListener(this); b1.addActionListener(this); bb.addActionListener(this); this.getContentPane().add(p2, "North"); this.getContentPane().add(p1, "South"); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setTitle("服务端"); this.setSize(600, 400); this.setVisible(true); } public static void main(String[] args) { JFrame.setDefaultLookAndFeelDecorated(true); new Server(); } public void actionPerformed(ActionEvent e) { if (e.getSource() == b1 || e.getSource() == t2) { try { t1.append("服务端说:" + t2.getText() + "\r\n"); wait.out.writeUTF(t2.getText()); } catch (IOException e1) { e1.printStackTrace(); } } else if (e.getSource() == bb) { try { ssock = new ServerSocket(5555); accepter = new Accepter(this, ssock); } catch (IOException e1) { e1.printStackTrace(); } } } } class Accepter extends Thread { Server fp; ServerSocket ssock; public Accepter(Server fp, ServerSocket ssock) { this.fp = fp; this.ssock = ssock; this.start(); } public void run() { Socket sock; try { sock = ssock.accept(); fp.wait = new Waiter(fp, sock); } catch (IOException e) { e.printStackTrace(); } } } class Waiter extends Thread { DataOutputStream out; DataInputStream in; Server fp; Socket sock; public Waiter(Server fp, Socket sock) { this.fp = fp; this.sock = sock; try { out = new DataOutputStream(sock.getOutputStream()); in = new DataInputStream(sock.getInputStream()); String msg = in.readUTF(); fp.t1.append("客户端说:" + msg + "\r\n"); out.writeUTF("欢迎你来！"); this.start(); } catch (IOException e) { e.printStackTrace(); } } public void run() { String msg = null; while (true) { try { msg = in.readUTF(); fp.t1.append("客户端说：" + msg + "\r\n"); } catch (IOException e) { e.printStackTrace(); break; } } try { in.close(); out.close(); sock.close(); fp.ssock.close(); JOptionPane.showMessageDialog(null, "系统出现错误或服务器已关闭!"); } catch (Exception e) { e.printStackTrace(); } } }