//利用GUI和网络编程知识，建立一个简单的聊天程序。package cn.itcast.udp.exercise;import java.awt.BorderLayout;import java.awt.Button;import java.awt.Color;import java.awt.Frame;import java.awt.Panel;import java.awt.TextArea;import java.awt.TextField;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.KeyAdapter;import java.awt.event.KeyEvent;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import java.io.BufferedWriter;import java.io.ByteArrayOutputStream;import java.io.FileInputStream;import java.io.FileWriter;import java.io.IOException;import .DatagramPacket;import .DatagramSocket;import .InetAddress;import java.text.SimpleDateFormat;import java.util.Date;public class GUI_Chat extends Frame {private static final long serialVersionUID = 1L;private Button sendButton;private Button clearButton;private Button logButton;private Button shakeButton;private TextField textField;private TextArea viewTextArea;private TextArea sendTextArea;private DatagramSocket socket;private BufferedWriter writer;/** 构造函数* 初始化* 生成2个Panel, 以及界面组件* 处理事件* 显示窗体* 启动接收消息的线程 */public GUI_Chat() {init();// 设置标题, 大小, 位置, 处理关闭事件generateSouthPanel();// 生成那边的Panel, 包含TextField和4个ButtongenerateCenterPanel();// 生成中间的Panel, 包含2个TextAreahandleChatEvent();// 各种事件的处理setVisible(true);// 显示new ReceiveThread().start();// 开启接收消息的线程}/** 初始化* 设置标题, 大小, 位置* 创建Socket和Writer*/private void init() {setTitle("GUI聊天室");setSize(400, 600);setLocation(600, 50);try {socket = new DatagramSocket();writer = new BufferedWriter(new FileWriter("msg.txt", true));} catch (Exception e) {e.printStackTrace();}}/** 创建南边的Panel* 其中包含用来输入IP的TextField和4个Button*/private void generateSouthPanel() {textField = new TextField(20);sendButton = new Button("发送");clearButton = new Button("清屏");logButton = new Button("记录");shakeButton = new Button("震动");Panel southPanel = new Panel();// 用来布局的Panel, 默认流式布局. 文本框和按钮都放在Panel中southPanel.add(textField);southPanel.add(sendButton);southPanel.add(clearButton);southPanel.add(logButton);southPanel.add(shakeButton);add(southPanel, BorderLayout.SOUTH);// Panel放在Frame的南边textField.setText("127.0.0.1");}/** 创建中间的Panel* 其中包含2个TextView*/private void generateCenterPanel() {viewTextArea = new TextArea();sendTextArea = new TextArea(5, 1);// 指定行数和列数, 列数由于是边界布局所以无效Panel centerPanel = new Panel();// 把Panel改为边界布局, 1个TextArea在中间, 另一个在南边centerPanel.setLayout(new BorderLayout());centerPanel.add(viewTextArea, BorderLayout.CENTER);centerPanel.add(sendTextArea, BorderLayout.SOUTH);add(centerPanel, BorderLayout.CENTER);// Panel放在Frame的中间viewTextArea.setEditable(false);// 用来显示的TextArea不能修改(会修改背景色为灰色)viewTextArea.setBackground(Color.WHITE);// 背景色改回白色}/** 处理各种事件* 窗体关闭* 4个按钮* 发送快捷键*/private void handleChatEvent() {addWindowListener(new WindowAdapter() {public void windowClosing(WindowEvent e) {try {socket.close();writer.close();System.exit(0);} catch (IOException e1) {e1.printStackTrace();}}});sendButton.addActionListener(new ActionListener() {// 发送按钮被点击的时候, 执行send()方法public void actionPerformed(ActionEvent e) {send();}});clearButton.addActionListener(new ActionListener() {public void actionPerformed(ActionEvent e) {viewTextArea.setText("");}});sendTextArea.addKeyListener(new KeyAdapter() {public void keyPressed(KeyEvent e) {if (e.isControlDown() && e.getKeyCode() == KeyEvent.VK_ENTER || e.isAltDown() && e.getKeyCode() == KeyEvent.VK_S) {e.consume();// 取消当前事件send();}}});logButton.addActionListener(new ActionListener() {public void actionPerformed(ActionEvent e) {showLog();}});shakeButton.addActionListener(new ActionListener() {public void actionPerformed(ActionEvent e) {sendData(new byte[] { -1 }, textField.getText());}});}/** 把指定的数据发送到指定的IP地址上*/private void sendData(byte[] data, String ip) {try {DatagramPacket packet = new DatagramPacket(data, data.length, InetAddress.getByName(ip), 6789);// 创建Packetsocket.send(packet);} catch (Exception e) {e.printStackTrace();}}/** 发送消息的方法* 发送之后会在TextView显示* 并且会保存聊天记录*/private void send() {String text = sendTextArea.getText();// 获取文本框中的文本String ip = textField.getText();// 获取IP地址ip = ip.trim().length() == 0 ? "255.255.255.255" : ip; // IP为空时, 群发try {String dateStr = getCurrentTime();// 获取当前时间synchronized(this) {// 为了让发送消息并显示之后才执行接收端的显示, 所以同步sendData(text.getBytes(), ip);String msg = dateStr + " 我对 " + (ip.equals("255.255.255.255") ? "所有人" : ip) + " 说:\r\n" + text + "\r\n\r\n";viewTextArea.append(msg);// 在TextArea中显示发送的消息writer.write(msg);// 保存聊天记录}sendTextArea.setText("");// 清空TextArea} catch (Exception e) {e.printStackTrace();}}/** 获取当前时间*/private String getCurrentTime() {Date date = new Date();SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");return sdf.format(date);}/** 用来接收数据的线程* 不停地接收数据, 显示到TextView, 并且保存聊天记录*/private class ReceiveThread extends Thread {public void run() {try {DatagramSocket socket = new DatagramSocket(6789);// 接收端SocketDatagramPacket packet = new DatagramPacket(new byte[1024000], 1024000);// 接收端Packetwhile (true) {// 循环接收socket.receive(packet);// 收到数据byte[] data = packet.getData();// 获取数据int len = packet.getLength();// 获取长度if (len == 1 && data[0] == -1) {// 收到特殊的消息, 震动shake();continue;}String ip = packet.getAddress().getHostAddress();// 获取IPString text = new String(data, 0, len);// 把收到的数据转为StringString timeStr = getCurrentTime();// 获取当前时间synchronized(GUI_Chat.this) {// 为了确保在发送端显示之后再显示, 所以同步String msg = timeStr + " " + ip + " 对我说:\r\n" + text + "\r\n\r\n";viewTextArea.append(msg);// 把收到的数据显示writer.write(msg);// 保存聊天记录}}} catch (Exception e) {e.printStackTrace();}}}/** 震动*/private void shake() {int x = getLocation().x;// 获取当前位置int y = getLocation().y;try {setLocation(x + 20, y + 20);Thread.sleep(20);setLocation(x - 20, y - 20);Thread.sleep(20);setLocation(x - 20, y + 20);Thread.sleep(20);setLocation(x + 20, y - 20);Thread.sleep(20);setLocation(x, y);} catch (InterruptedException e) {e.printStackTrace();}}/** 显示聊天记录* 从文件中读取数据, 显示到TextView*/private void showLog() {try {viewTextArea.setText("");// 清空viewTextAreawriter.flush();// 刷出缓冲区中数据FileInputStream fis = new FileInputStream("msg.txt");ByteArrayOutputStream baos = new ByteArrayOutputStream();byte[] buffer = new byte[1024];int len;while ((len = fis.read(buffer)) != -1)// 从文件读取数据到内存baos.write(buffer, 0, len);fis.close();baos.close();String log = new String(baos.toByteArray());// 把内存中数据转为StringviewTextArea.setText(log);// 显示到viewTextArea} catch (IOException e) {e.printStackTrace();}}/** 测试方法, 创建聊天室对象*/public static void main(String[] args) {new GUI_Chat();}}
