Java 客戶端服務器程序 學習筆記

//Server.java

package com.mulThread;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.net.*;
import java.io.*;
import java.util.*;

/**
 *
 * @E-mail:[email protected]
 *
 * @author:young master
 * 
 * @version 1.0
 * 
 * @any questions,please reply to me for deeping improvements
 */

public class Server extends JFrame {
	JPanel contentPane;

	JMenuBar jMenuBar1 = new JMenuBar();

	JMenu jMenuFile = new JMenu();

	JMenuItem jMenuFileExit = new JMenuItem();

	JMenu jMenuHelp = new JMenu();

	JMenuItem jMenuHelpAbout = new JMenuItem();

	JLabel statusBar = new JLabel();

	BorderLayout borderLayout1 = new BorderLayout();

	JPanel jPanel1 = new JPanel();

	BorderLayout borderLayout2 = new BorderLayout();

	JLabel jLabel1 = new JLabel();

	static java.awt.List jList1 = new java.awt.List(13);

	JScrollPane scrollpane = new JScrollPane(jList1);

	// 以下爲網絡相關變量
	static Vector clients = new Vector(10); // 用vector向量數組存儲連接客戶變量

	static ServerSocket server = null; // 建立服務器socket

	static int active_connects = 0; // 用來存儲目前連接的客戶數

	static Socket socket = null; // 用來存儲一個套接字連接

	// chatServer main method
	public static void main(String[] args) {
		try {
			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
		} catch (Exception e) {
			e.printStackTrace();
		}
		Server chatServer1 = new Server(); // 實例化一個chatServer類
		chatServer1.show();
		System.out.println("Server starting ...");

		try {
			server = new ServerSocket(2525); // 使用端口2525初始化服務器套接字
		} catch (IOException e) {
			System.out.println("Error:" + e);
		}
		while (true) {

			if (clients.size() < 5) // 當客戶數小於5個時開始連接
			{
				try {
					socket = server.accept(); // 用來存儲連接上的客戶socket
					if (socket != null) {
						System.out.println(socket + "連接"); // 在控制檯打印客戶連接信息

					}
				} catch (IOException e) {
					System.out.println("Error:" + e);
				}
				int i = 0;

				do {

					Client c = new Client(socket); // 定義並實例化一個Client線程類，一個就對應一個客戶連接
					clients.addElement(c); // 加入clients數組中
					if (checkName(c)) // 調用checkName方法驗證c的合法性
					{
						int connum = ++chatServer1.active_connects; // 定義connum來存儲活動連接數
						String constr = "目前有" + connum + "客戶相連"; // 在狀態欄裏顯示連接數
						chatServer1.statusBar.setText(constr);
						Client listdata = (Client) clients.elementAt(i); // 將連接客戶的socket信息存儲進listdata數組

						chatServer1.jList1.addItem(listdata.ip + "連接", i); // 將客戶socket信息寫入list框
						c.start(); // 啓動線程
						notifyRoom(); // 用notifyRoom方法來監視聊天室連接變化
						// 不斷改變clients數組並刷新客戶端信息

					} else {
						// 如果名字不合法
						c.ps.println("TAKEN");

						disconnect(c);

					}
					i++;
					break;

				} while (i < clients.size());

			} else // 如果clients數組超過了5個
			{
				try {
					Thread.sleep(200);
				} catch (InterruptedException e) {
				}
			}
		}// end of while
	}// end of main method

	/** Construct the frame */
	public Server() // chatServer類的構造器用來初始化一些UI信息
	{
		enableEvents(AWTEvent.WINDOW_EVENT_MASK);
		try {
			jbInit();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/** Component initialization */
	private void jbInit() throws Exception {
		// setIconImage(Toolkit.getDefaultToolkit().createImage(Frame1.class.getResource("[Your
		// Icon]")));
		contentPane = (JPanel) this.getContentPane();
		contentPane.setLayout(borderLayout1);
		this.setSize(new Dimension(400, 300));
		this.setTitle("簡易聊天服務器端");
		statusBar.setText("目前的連接數爲：");

		jMenuFile.setText("File");
		jMenuFileExit.setText("Exit");
		jMenuFileExit.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				jMenuFileExit_actionPerformed(e);
			}
		});
		jMenuHelp.setText("Help");
		jMenuHelpAbout.setText("About");
		jMenuHelpAbout.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				jMenuHelpAbout_actionPerformed(e);
			}
		});

		jPanel1.setLayout(borderLayout2);
		jLabel1.setText("服務器端連接客戶");
		jMenuFile.add(jMenuFileExit);
		jMenuHelp.add(jMenuHelpAbout);
		jMenuBar1.add(jMenuFile);
		jMenuBar1.add(jMenuHelp);
		this.setJMenuBar(jMenuBar1);
		contentPane.add(statusBar, BorderLayout.SOUTH);
		contentPane.add(jPanel1, BorderLayout.CENTER);
		jPanel1.add(jLabel1, BorderLayout.NORTH);
		jPanel1.add(scrollpane, BorderLayout.CENTER);

	}// end of jbinit

	/** File | Exit action performed */
	public void jMenuFileExit_actionPerformed(ActionEvent e) // 實現退出菜單方法
	{
		sendClients(new StringBuffer("QUIT")); // 向客戶端發送斷開連接信息
		closeAll(); // 調用closeAll方法關閉所有連接
		System.exit(0);
	}

	/** Help | About action performed */
	public void jMenuHelpAbout_actionPerformed(ActionEvent e) // 實現about對話框，意義不大，可以去掉
	{
		AboutChat dlg = new AboutChat(this);
		Dimension dlgSize = dlg.getPreferredSize();
		Dimension frmSize = getSize();
		Point loc = getLocation();
		dlg.setLocation((frmSize.width - dlgSize.width) / 2 + loc.x,
				(frmSize.height - dlgSize.height) / 2 + loc.y);
		dlg.setModal(true);
		dlg.show();
	}

	/** Overridden so we can exit when window is closed */
	protected void processWindowEvent(WindowEvent e) // 實現關閉服務器程序要進行的操作
	{
		super.processWindowEvent(e);
		if (e.getID() == WindowEvent.WINDOW_CLOSING) {
			jMenuFileExit_actionPerformed(null);
		}
	}

	/* 以下實現各種方法 */
	public static void notifyRoom() // 用來監視連接信息，不斷刷新clients數組並刷新客戶端用戶列表信息
	{
		StringBuffer people = new StringBuffer("PEOPLE");
		for (int i = 0; i < clients.size(); i++) {
			Client c = (Client) clients.elementAt(i);
			people.append(":" + c.name);

		}
		sendClients(people); // 用sendClients方法向客戶端發送信息
	}

	public static synchronized void sendClients(StringBuffer msg) // 實現sendClients方法專用來向每個連接的客戶端發送信息
	{
		for (int i = 0; i < clients.size(); i++) {
			Client c = (Client) clients.elementAt(i);
			c.send(msg);
		}
	}

	public static void closeAll() // 實現關閉所有連接信息
	{
		while (clients.size() > 0) // 遍歷clients數組刪除所有連接客戶信息
		{
			Client c = (Client) clients.firstElement();
			try {
				c.socket.close();
			} catch (IOException e) {
				System.out.println("Error:" + e);
			} finally {
				clients.removeElement(c);
			}
		}// end of while
	}// end of closeAll method

	public static boolean checkName(Client newclient) // 實現檢查連接客戶的socket信息是否合法
	{
		for (int i = 0; i < clients.size(); i++) {
			Client c = (Client) clients.elementAt(i);
			if ((c != newclient) && c.equals(newclient.name))
				return false;
		}
		return (true);
	}// end of checkName method

	public static synchronized void disconnect(Client c) // 實現斷開單個客戶的方法
	{
		try {
			jList1.addItem(c.ip + "斷開連接"); // 在服務器端程序的list框中顯示斷開信息

			Server.active_connects--; // 將連接數減1
			c.send(new StringBuffer("QUIT")); // 向客戶發送斷開連接信息
			c.socket.close();

		} catch (IOException e) {
			System.out.println("Error:" + e);
		} finally {
			clients.removeElement(c); // 從clients數組中刪除此客戶的相關socket等信息
		}
	}

}

class Client extends Thread // 實現 Client線程類
{
	Socket socket; // 用來存儲一個連接客戶的socket信息

	String name; // 用來存儲客戶的連接姓名

	String ip; // 用來存儲客戶的ip信息

	DataInputStream dis; // 用來實現接受從客戶端發來的數據流

	PrintStream ps; // 用來實現向客戶端發送信息的打印流

	public void send(StringBuffer msg) // 實現想客戶端發送信息的方法
	{
		ps.println(msg); // 用打印流發送信息
		ps.flush();
	}

	public Client(Socket s) // Client線程類的構造器
	{
		socket = s;
		try {
			dis = new DataInputStream(s.getInputStream()); // 存儲特定客戶socket的輸入流接受s這個客戶發送到服務器端的信息
			ps = new PrintStream(s.getOutputStream()); // 存儲特定客戶socket的輸出流發送服務器給s這個客戶的信息
			String info = dis.readLine(); // 讀取接受來的信息

			StringTokenizer stinfo = new StringTokenizer(info, ":"); // 用StringTokenizer類來讀取用"："分段字符
			String head = stinfo.nextToken(); // head用來存儲類似於關鍵字的頭信息
			if (stinfo.hasMoreTokens())
				name = stinfo.nextToken(); // 關鍵字後的第二段數據是客戶名信息
			if (stinfo.hasMoreTokens())
				ip = stinfo.nextToken(); // 關鍵字後的第三段數據是客戶ip信息
			System.out.println(head); // 在控制檯打印頭信息
		} catch (IOException e) {
			System.out.println("Error:" + e);
		}
	}// end of Client constrator

	public void run() // 線程運行方法
	{
		while (true) {
			String line = null;
			try {
				line = dis.readLine(); // 讀取客戶端發來的數據流

			} catch (IOException e) {
				System.out.println("Error" + e);
				Server.disconnect(this);
				Server.notifyRoom();
				return;
			}

			if (line == null) // 客戶已離開
			{
				Server.disconnect(this);
				Server.notifyRoom();
				return;
			}

			StringTokenizer st = new StringTokenizer(line, ":");
			String keyword = st.nextToken();

			if (keyword.equals("MSG")) // 如果關鍵字是MSG則是客戶端發來的聊天信息
			{
				StringBuffer msg = new StringBuffer("MSG:"); // 在服務器端再重新建立一個字符緩衝
				msg.append(name);
				msg.append(st.nextToken("\0"));
				Server.sendClients(msg); // 再將某個客戶發來的聊天信息發送到每個連接客戶的聊天欄中
			} else if (keyword.equals("QUIT")) // 如果關鍵字是QUIT則是客戶端發來斷開連接的信息
			{

				Server.disconnect(this); // 服務器斷開與這個客戶的連接
				Server.notifyRoom(); // 繼續監聽聊天室並刷新其他客戶的聊天人名list
				this.stop();
			}
		}
	}
} // end of class Client

//ClientChat.java

package com.mulThread;

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import java.net.*;
import java.io.*;
import java.util.*;

/**
*
* @E-mail:[email protected]
*
* @author:young master
* 
* @version 1.0
* 
* @any questions,please reply to me for deeping improvements
*/

public class ClientChat extends Applet {
	/* 以下用於定義UI變量 */
	Panel panel1 = new Panel(); // 用於放置輸入姓名和連接兩個按鈕

	BorderLayout borderLayout1 = new BorderLayout();

	Panel panel2 = new Panel(); // 用於放置聊天信息顯示和聊天人員列表

	Panel panel3 = new Panel(); // 用於放置發送信息區域

	FlowLayout flowLayout1 = new FlowLayout();

	FlowLayout flowLayout2 = new FlowLayout();

	Label label1 = new Label();

	TextField name_txt = new TextField(15);

	Button button1 = new Button();

	Button button2 = new Button();

	TextArea chat_txt = new TextArea(15, 30);

	Label label2 = new Label();

	Button button3 = new Button();

	TextField msg_txt = new TextField(20);

	java.awt.List list1 = new java.awt.List(13);

	/* 以下定義數據流和網絡變量 */
	Socket soc = null; // 定義連接套接字

	PrintStream ps = null; // 定義打印流

	Listen listen = null; // 定義一個客戶端線程

	public void init() // 初始化圖形界面
	{
		resize(475, 350);
		this.setLayout(borderLayout1);
		panel2.setLayout(flowLayout1);
		panel3.setLayout(flowLayout2);
		label1.setText("用戶名：");

		button1.setLabel("連接");
		button2.setLabel("斷開連接");

		chat_txt.setEditable(false);
		panel2.setBackground(Color.cyan);
		panel1.setBackground(Color.cyan);
		label2.setText("聊天信息：");
		button3.setLabel("發送");
		msg_txt.setText("請輸入聊天信息");
		panel3.setBackground(Color.cyan);
		this.add(panel1, BorderLayout.NORTH);
		panel1.add(label1, null);
		panel1.add(name_txt, null);
		panel1.add(button1, null);
		panel1.add(button2, null);
		this.add(panel2, BorderLayout.CENTER);
		panel2.add(chat_txt, null);
		panel2.add(list1, null);
		this.add(panel3, BorderLayout.SOUTH);
		panel3.add(label2, null);
		panel3.add(msg_txt, null);
		panel3.add(button3, null);
	}

	public boolean action(Event evt, Object obj) // 事件觸發代碼
	{
		if (evt.target instanceof Button) {
			String label = (String) obj;
			if (label.equals("連接")) // 如果點擊連接後
			{
				if (soc == null) {
					try {
						soc = new Socket(InetAddress.getLocalHost(), 2525); // 使用端口2525實例化一個本地套接字
						System.out.println(soc); // 在控制檯打印實例化的結果
						ps = new PrintStream(soc.getOutputStream()); // 將ps指向soc的輸出流
						StringBuffer info = new StringBuffer("INFO: "); // 定義一個字符緩衝存儲發送信息
						// 其中INFO爲關鍵字讓服務器識別爲連接信息
						// 並將name和ip用"："分開，在服務器端將用一個
						// StringTokenizer類來讀取數據
						String userinfo = name_txt.getText() + ":"
								+ InetAddress.getLocalHost().toString();
						ps.println(info.append(userinfo));

						ps.flush();
						listen = new Listen(this, name_txt.getText(), soc); // 將客戶端線程實例化
						listen.start(); // 啓動線程
					} catch (IOException e) {
						System.out.println("Error:" + e);
						disconnect();
					}
				} // end of if
			}// end of if
			else if (label.equals("斷開連接")) // 如果點擊斷開連接按鈕則運行disconnect()
			{
				disconnect();
			} else if (label.equals("發送")) // 如果點擊發送按鈕
			{
				if (soc != null) {
					StringBuffer msg = new StringBuffer("MSG: "); // 定義並實例化一個字符緩衝存儲發送的聊天信息
					// 其中MSG爲關鍵詞
					try {
						String msgtxt = new String(msg_txt.getText());
					} catch (Exception e) {
					}

					ps.println(msg.append(msg_txt.getText())); // 用打印流發送聊天信息
					ps.flush();
				}
			}
		}
		return true;
	} // end of method action

	public void disconnect() // 客戶端點擊斷開連接要運行的方法
	{
		if (soc != null) {
			try {
				listen.suspend();
				ps.println("QUIT"); // 用打印流發送QUIT信息通知服務器斷開此次通信
				ps.flush();
				soc.close(); // 關閉套接字
			} catch (IOException e) {
				System.out.println("Error:" + e);
			} finally {

			}
		}// end of if
	}

	class Listen extends Thread // 客戶端線程類用來監聽服務器傳來的信息
	{
		String name = null; // 用來存儲客戶端連接後的name信息

		DataInputStream dis = null; // 用來實現客戶端接受服務器數據的輸入流

		PrintStream ps = null; // 用來實現從客戶端發送數據到服務器的打印流

		Socket socket = null; // 用來存儲客戶端的socket信息

		ClientChat parent = null; // 用來存儲當前運行的chatApplet實例

		public Listen(ClientChat p, String n, Socket s) // Listen類的構造器
		{
			// 接受參數
			parent = p;
			name = n;
			socket = s;

			try {
				// 實例化兩個數據流
				dis = new DataInputStream(s.getInputStream());
				ps = new PrintStream(s.getOutputStream());

			} catch (IOException e) {
				System.out.println("Error:" + e);
				parent.disconnect();
			}
		} // end of Listen constractor

		public void run() // 線程運行方法
		{
			String msg = null;
			while (true) {
				try {
					msg = dis.readLine();
				} // 讀取從服務器傳來的信息
				catch (IOException e) {
					System.out.println("Error:" + e);
					parent.disconnect();
				}
				if (msg == null) // 如果從服務器傳來的信息爲空則斷開此次連接
				{
					parent.listen = null;
					parent.soc = null;
					parent.list1.clear();
					return;
				}
				StringTokenizer st = new StringTokenizer(msg, ":"); // 用StringTokenizer類來實現讀取分段字符
				String keyword = st.nextToken(); // 讀取信息頭即關鍵字用來識別是何種信息

				if (keyword.equals("PEOPLE")) // 如果是PEOPLE則是服務器發來的客戶連接信息
				// 主要用來刷新客戶端的用戶列表
				{
					parent.list1.clear();
					while (st.hasMoreTokens()) // 遍歷st取得目前所連接的客戶
					{
						String str = st.nextToken();
						parent.list1.addItem(str);
					}
				} else if (keyword.equals("MSG")) // 如果關鍵字是MSG則是服務器傳來的聊天信息
				// 主要用來刷新客戶端聊天信息區將每個客戶的聊天內容顯示出來
				{
					String usr = st.nextToken();
					parent.chat_txt.appendText(usr);
					parent.chat_txt.appendText(st.nextToken("\0"));
					parent.chat_txt.appendText("\n\n");
				} else if (keyword.equals("QUIT")) // 如果關鍵字是QUIT則是服務器關閉的信息
				// 用來切斷此次連接
				{
					System.out.println("Quit");
					try {
						parent.listen.stop();
						parent.listen = null;
						parent.soc.close();
						parent.soc = null;
					} catch (IOException e) {
						System.out.println("Error:" + e);
					}
					parent.list1.clear();

					return;
				}
			}

		} // end of run method
	} // end of Listen inner class

} // end of chatApplet class

//AboutChat.java

package com.mulThread;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;

/**
*
* @E-mail:[email protected]
*
* @author:young master
* 
* @version 1.0
* 
* @any questions,please reply to me for deeping improvements
*/

public class AboutChat extends JDialog implements ActionListener {

	JPanel panel1 = new JPanel();

	JPanel panel2 = new JPanel();

	JPanel insetsPanel1 = new JPanel();

	JPanel insetsPanel2 = new JPanel();

	JPanel insetsPanel3 = new JPanel();

	JButton button1 = new JButton();

	JLabel imageLabel = new JLabel();

	JLabel label1 = new JLabel();

	JLabel label2 = new JLabel();

	JLabel label3 = new JLabel();

	JLabel label4 = new JLabel();

	BorderLayout borderLayout1 = new BorderLayout();

	BorderLayout borderLayout2 = new BorderLayout();

	FlowLayout flowLayout1 = new FlowLayout();

	GridLayout gridLayout1 = new GridLayout();

	String product = "product:少爺精簡版--聊天服務器端";

	String author = "author:young master   " +
			"any questions,please reply to me for deeping improvements";

	String email = "@E-mail:[email protected]";

	String comments = "本聊天室服務器端實現了多線程客戶連接和顯示連接信息";

	public AboutChat(Frame parent) {
		super(parent);
		enableEvents(AWTEvent.WINDOW_EVENT_MASK);
		try {
			jbInit();
		} catch (Exception e) {
			e.printStackTrace();
		}
		pack();
	}

	private void jbInit() throws Exception {
		//imageLabel.setIcon(new ImageIcon(Frame1_AboutBox.class.getResource("[Your Image]")));
		this.setTitle("少爺精簡版--聊天服務器端");
		setResizable(false);
		panel1.setLayout(borderLayout1);
		panel2.setLayout(borderLayout2);
		insetsPanel1.setLayout(flowLayout1);
		insetsPanel2.setLayout(flowLayout1);
		insetsPanel2.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
		gridLayout1.setRows(4);
		gridLayout1.setColumns(1);
		label1.setText(product);
		label2.setText(author);
		label3.setText(email);
		label4.setText(comments);
		insetsPanel3.setLayout(gridLayout1);
		insetsPanel3.setBorder(BorderFactory.createEmptyBorder(10, 60, 10, 10));
		button1.setText("Ok");
		button1.addActionListener(this);
		insetsPanel2.add(imageLabel, null);
		panel2.add(insetsPanel2, BorderLayout.WEST);
		this.getContentPane().add(panel1, null);
		insetsPanel3.add(label1, null);
		insetsPanel3.add(label2, null);
		insetsPanel3.add(label3, null);
		insetsPanel3.add(label4, null);
		panel2.add(insetsPanel3, BorderLayout.CENTER);
		insetsPanel1.add(button1, null);
		panel1.add(insetsPanel1, BorderLayout.SOUTH);
		panel1.add(panel2, BorderLayout.NORTH);
	}

	/**Overridden so we can exit when window is closed*/
	protected void processWindowEvent(WindowEvent e) {
		if (e.getID() == WindowEvent.WINDOW_CLOSING) {
			cancel();
		}
		super.processWindowEvent(e);
	}

	/**Close the dialog*/
	void cancel() {
		dispose();
	}

	/**Close the dialog on a button event*/
	public void actionPerformed(ActionEvent e) {
		if (e.getSource() == button1) {
			cancel();
		}
	}
}