JAVA22.docx

1、JAVA22第二十二课 网络编程案例：2201 URL应用举例案例文件：URLReader.java目 标：使用URL类，体会网络网络数据传输代 码：/ * 范例名称：URL应用举例 * 源文件名称：URLReader.java * 要 点： * 1. URL概念及URL类的使用 * 2. URL类的openStream()及其它方法 */import java.io.*;import .*;public class URLReader public static void main(String args) try URL tirc = new URL( BufferedReader in

2、= new BufferedReader(new InputStreamReader(tirc.openStream(); String s; while(s = in.readLine()!=null) System.out.println(s); in.close(); catch(MalformedURLException e) System.out.println(e); catch(IOException e) System.out.println(e); 案例：2202 简单的client/server程序案例文件：TestServer.java/TestClient.java目

3、标：掌握Java Socket编程机制及其实现代 码：/ * 范例名称：简单的client/server程序 * 源文件名称：TestClient.java/TestServer.java * 要 点： * 1. Java Socket编程步骤 * 2. Socket/ServerSocket类用法 * 3. 通过Socket对象可以获取通信对方Socket的信息 */文件TestServer.javaimport .*;import java.io.*;public class TestServer public static void main(String args) try Serve

4、rSocket s = new ServerSocket(8888); while (true) Socket s1 = s.accept(); OutputStream os = s1.getOutputStream(); DataOutputStream dos = new DataOutputStream(os); dos.writeUTF(Hello, + s1.getInetAddress() + port# +s1.getPort() + bye-bye!); dos.close(); s1.close(); catch (IOException e) System.out.pri

5、ntln(程序运行出错: + e); /文件TestClient.javaimport .*;import java.io.*;public class TestClient public static void main(String args) try Socket s1 = new Socket(127.0.0.1, 8888); InputStream is = s1.getInputStream(); DataInputStream dis = new DataInputStream(is); System.out.println(dis.readUTF(); dis.close()

6、; s1.close(); catch (ConnectException connExc) System.err.println(服务器连接失败！); catch (IOException e) 案例：2203 URL提取及应用举例案例文件：URLParser.java目 标：在Java应用程序中实现网络数据传输和处理代 码：/ * 范例名称：URL提取及应用举例 * 源文件名称：URLParser.java * 描 述：通过一个URL入口，读出该页上的所有超连接 * 要 点： * 1. URL/URLConnection类及相关方法的使用 * 2. Collection/ArrayList

7、/Iterator/StringTokenizer类 * 3. 注释的使用 * 4. 系统属性的使用 * 用 法：java URLParser * 如果使用了代理服务器，则添加相应的系统属性： * java -Dhttp.proxyHost= -Dhttp.proxyPort= URLParser * author bily * version v1.0 */ import java.io.IOException;import java.io.BufferedReader;import java.io.InputStreamReader;import java.util.Collection;

8、import java.util.ArrayList;import java.util.Iterator;import java.util.StringTokenizer; import .URL;import .URLConnection;import .MalformedURLException;public class URLParser /判断一段字串中是否含有子串http(超连接) private boolean hasMatch(String token) return token.indexOf(http:)!=-1; /* *从含有http子串的字符串中提取完整的URL */

9、private String trimURL(String url1) String tempStr=null; int beginIndex=url1.indexOf(http); int endIndex=url1.length(); tempStr=url1.substring(beginIndex,endIndex); endIndex=tempStr.indexOf(); if(endIndex=-1) endIndex=tempStr.length(); return tempStr.substring(0,endIndex); /* *遍历输入的页面里的内容，以找出url *pa

10、ram urlString 输入的URL *return urls ArrayList对象，其中包含已提取出的全部URL信息 */ public Collection searchURL(String urlString) URL url2=null; URLConnection conn=null; String nextLine=null; StringTokenizer tokenizer=null; Collection urlCollection=new ArrayList(); try url2=new URL(urlString); conn=url2.openConnectio

11、n(); conn.setDoOutput(true); conn.connect(); BufferedReader Reader1=new BufferedReader(new InputStreamReader(conn.getInputStream(); while(nextLine=Reader1.readLine()!=null) tokenizer=new StringTokenizer(nextLine); while(tokenizer.hasMoreTokens() String urlToken=tokenizer.nextToken(); if (hasMatch(ur

12、lToken) urlCollection.add(trimURL(urlToken); catch(MalformedURLException ex) ex.printStackTrace(); catch(IOException ex) ex.printStackTrace(); return urlCollection; /* *主方法，需要一个命令行参数-要处理的URL */ public static void main(String args) if(args.length!=1) System.out.println(用法: java URLParser ); System.ex

13、it(-1); String url3=args0; System.out.println(Searching web site:+url3); URLParser example=new URLParser(); Collection urlCollection=example.searchURL(url3); Iterator iter=urlCollection.iterator(); while (iter.hasNext() System.out.println(iter.next(); 案例：2204 聊天室程序案例文件：CreateTemp.java目 标：ChatServer.

14、java/ChatClient.java代 码：/ * 范例名称：聊天室程序 * 源文件名称：ChatClient.java/ChatServer.java * 要 点： * 1. Java Socket编程 * 2. 多线程编程 * 3. 程序体系结构及设计思想 */源程序ChatServer.javaimport java.io.*;import .*;import java.awt.*;import java.awt.event.*;import java.util.Vector;public class ChatServer extends Frame implements Windo

15、wListener TextArea display; int num=1; int port; ServerSocket server; BufferedReader input; BufferedWriter output; Vector msgV; /* *构造方法完成初始化工作 */ public ChatServer(int port1) super(Chat Server,Running.); display=new TextArea(200,300); this.add(Center,display); addWindowListener(this); setSize(300,4

16、00); show(); this.port=port1; msgV=new Vector(10); /* *关闭窗口事件 *1.显示正在关闭chat server *2.在消息队列msgV中加入shutdown字符串 *3.线程睡眠5001ms */ public void windowClosing(WindowEvent e) display.append(Server is now shutting down.n); display.append(Informing the Chatters.n); display.append(Please Wait.); msgV.add(shut

17、down); tryThread.sleep(5000); catch(Exception e2) dispose(); System.exit(0); public void windowOpened(WindowEvent e) public void windowActivated(WindowEvent e) public void windowClosed(WindowEvent e) public void windowDeactivated(WindowEvent e) public void windowDeiconified(WindowEvent e) public voi

18、d windowIconified(WindowEvent e) public void run() try server=new ServerSocket(port,3); display.append(Chat Server is now running!n); while(true) Socket clientSocket=server.accept(); clientConnection conn=new clientConnection(clientSocket,num,display,msgV); display.append(No +(num+)+ chatmaten); cat

19、ch(IOException e) e.printStackTrace(); public static void main(String args) ChatServer chatServer=new ChatServer(7); chatServer.run(); class clientConnection extends Thread String name; Socket cSocket; BufferedReader input; PrintWriter output; int num; TextArea display; Vector msgV; public clientCon

20、nection(Socket cSocket,int num,TextArea display,Vector msgV) try input = new BufferedReader(new InputStreamReader(cSocket.getInputStream(); output = new PrintWriter(cSocket.getOutputStream(),true); this.name=input.readLine(); catch(IOException e) e.printStackTrace(); this.cSocket = cSocket; this.num

21、=num; this.display=display; this.msgV=msgV; this.start(); synchronized public void run() String line; try while(true) line = input.readLine(); if(line.equals(End) display.append( System Message: +name+ is out !n); break; if(line.equals(PleaseSendALL) if(!msgV.isEmpty() int ii=msgV.size() ; output.pr

22、intln(ii); for(int I=0;ImsgV.size();I+) output.println(msgV.get(I); /output.println(end); else output.println(0); else line=name+ say:+ line+n; display.append(line); msgV.add(line); catch(IOException ex) ex.printStackTrace(); finally try cSocket.close(); catch(IOException ex2) ex2.printStackTrace();

23、 /源程序ChatServer.javaimport java.io.*;import .*;import java.awt.*;import java.awt.event.*;public class ChatClient extends Frame implements Runnable,WindowListener,ActionListener int num=1; boolean flag=true; Thread receiveThread; Socket sClient; BufferedReader input; PrintWriter output; String name;

24、Label helloLabel=new Label(Please input :); TextField sendText=new TextField(20); Button sendButton=new Button(Send); TextArea messageText=new TextArea(100,20); public ChatClient(String name,String servername) super(I am +name); try sClient = new Socket(servername,7); input =new BufferedReader(new I

25、nputStreamReader(sClient.getInputStream(); output = new PrintWriter(sClient.getOutputStream(),true); output.println(name); catch(IOException e) e.printStackTrace(); setBackground(new Color(220,220,255); sendText.addActionListener(this); sendButton.addActionListener(this); sendButton.setSize(20,30);

26、Panel cp=new Panel(); cp.add(helloLabel); cp.add(sendText); cp.add(sendButton); Panel sp=new Panel(); sp.add(messageText); add(North,cp); add(Center,messageText); addWindowListener(this); setSize(400,400); show(); receiveThread=new Thread(this); receiveThread.start(); public void windowActivated(WindowEvent e) public void windowClosed(WindowEvent e) public void windowClosing(WindowEvent e) flag=false; tryThread.sleep(5000); catch(Exception e2) output.println(End); dispose(); System.exit(0); public void windowDeactivated(WindowEvent e) public void windowDeico