Java网络编程一

1.InetAddress的应用

import java.util.List;

import java.math.BigDecimal;

import java.net.InetAddress;

import java.net.UnknownHostException;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collection;

import java.util.Collections;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.LinkedList;

import java.util.Scanner;

import java.util.Set;

import java.util.Stack;

import javax.naming.spi.DirStateFactory.Result;

import org.omg.PortableInterceptor.DISCARDING;

import java.util.Map;

import java.util.Queue;

/**

 * InetAddress类

 * @author 16114

 *

 */

public class Main{

    public static void main(String[] args) {

        try {

            InetAddress address = InetAddress.getLocalHost();

            System.out.println("计算机名：" + address.getHostName());

            System.out.println("IP地址：" + address.getHostAddress());

            byte[] bytes = address.getAddress();

            System.out.println("字节数组形式的IP：" + Arrays.toString(bytes));

            System.out.println(address);

        } catch (UnknownHostException e) {

            e.printStackTrace();

        }

        try {

            InetAddress address2 = InetAddress.getByName("Roni");

            System.out.println(address2.getHostName());

            System.out.println(address2.getHostAddress());

        } catch (UnknownHostException e) {

            e.printStackTrace();

        }

    }

}

2.URL

import java.util.List;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.math.BigDecimal;

import java.net.InetAddress;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.UnknownHostException;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collection;

import java.util.Collections;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.LinkedList;

import java.util.Scanner;

import java.util.Set;

import java.util.Stack;

import javax.naming.spi.DirStateFactory.Result;

import org.omg.PortableInterceptor.DISCARDING;

import java.util.Map;

import java.util.Queue;

/**

 * URL类

 * @author 16114

 *

 */

public class Main{

    public static void main(String[] args) {

        try {

            URL url = new URL("http://www.baidu.com");

            try {

                InputStream is = url.openStream();

                InputStreamReader isr = new InputStreamReader(is,"utf-8");

                BufferedReader br = new BufferedReader(isr);

                String data = br.readLine();

                while(data!=null) {

                    System.out.println(data);

                    data=br.readLine();

                }

                br.close();

                isr.close();

                is.close();

            } catch (IOException e) {

                e.printStackTrace();

            }

        } catch (MalformedURLException e) {

            e.printStackTrace();

        }

    }

}

3.客户端向服务器端的通信

Server

package com.zrl.thread;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.net.ServerSocket;

import java.net.Socket;

import java.util.Scanner;

/**

 * 基于TCP协议的Socket协议

 * 服务端

 * @author 16114

 *

 */

public class Server {

    public static void main(String[] args) {

        //1.创建一个服务器端Socket，即ServerSocket，指定绑定的端口

        try {

            ServerSocket serverSocket = new  ServerSocket(8888);

            //2.调用accept（）方法开始监听，等待客户端的连接

            System.out.println("***服务器即将启动，等待客户端的链接***");

            Socket socket = serverSocket.accept();

            //3.获取输入流，并读取客户端信息

            InputStream is = socket.getInputStream();

            InputStreamReader isr = new InputStreamReader(is);

            BufferedReader br = new BufferedReader(isr);

            String info = null;

            while((info=br.readLine())!=null) {

                System.out.println("我是服务器，客户端说：" + info);

            }

            socket.shutdownInput();

            //4.关闭相关资源

            br.close();

            isr.close();

            is.close();

            socket.close();

            serverSocket.close();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

}

Client

package com.zrl.thread;

import java.io.IOException;

import java.io.OutputStream;

import java.io.PrintWriter;

import java.net.Socket;

import java.net.UnknownHostException;

public class Client {

    public static void main(String[] args) {

        //1.创建客户端Socket，指定服务器端地址和端口

        Socket socket;

        try {

            socket = new Socket("localhost", 8888);

            //2.获取输出流，向服务器发送消息

            OutputStream os = socket.getOutputStream();

            PrintWriter pw = new PrintWriter(os);//将输出流包装为打印流

            pw.write("用户名：admin;密码:123");

            pw.flush();

            socket.shutdownInput();

            //3.关闭资源

            pw.close();

            os.close();

            socket.close();

        } catch (UnknownHostException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

}

一个服务端，多个客户端

Server.java

package com.zrl.thread;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.PrintWriter;

import java.net.InetAddress;

import java.net.ServerSocket;

import java.net.Socket;

import java.util.Scanner;

/**

 * 基于TCP协议的Socket协议

 * 服务端

 * @author 16114

 *

 */

public class Server {

    public static void main(String[] args) {

        //1.创建一个服务器端Socket，即ServerSocket，指定绑定的端口

        try {

            ServerSocket serverSocket = new  ServerSocket(8888);

            //2.调用accept（）方法开始监听，等待客户端的连接

            System.out.println("***服务器即将启动，等待客户端的链接***");

            Socket socket = null;

            //记录客户端的数量

            int cnt = 0;

            //循环监听等待客户端的连接

            while(true) {

                //调用accept（）方法开始监听，等待客户端的连接

                socket = serverSocket.accept();

                //创建一个新线程

                ServerThread serverThread = new ServerThread(socket);

                //启动线程

                serverThread.start();

                cnt++;

                System.out.println("客户端的数量：" + cnt);

                InetAddress address = socket.getInetAddress();

                System.out.println("当前客户端的IP：" + address.getHostAddress());

            }

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

}

Client.java

package com.zrl.thread;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.PrintWriter;

import java.net.Socket;

import java.net.UnknownHostException;

public class Client {

    public static void main(String[] args) {

        //1.创建客户端Socket，指定服务器端地址和端口

        Socket socket;

        try {

            socket = new Socket("localhost", 8888);

            //2.获取输出流，向服务器发送消息

            OutputStream os = socket.getOutputStream();

            PrintWriter pw = new PrintWriter(os);//将输出流包装为打印流

            pw.write("用户名：admin; 密码:456");

            pw.flush();

            socket.shutdownOutput();

            //3.获取输入流并且读取服务器端的响应信息

            InputStream is = socket.getInputStream();

            InputStreamReader isr = new InputStreamReader(is);

            BufferedReader br = new BufferedReader(isr);

            String info = null;

            while((info=br.readLine())!=null) {

                System.out.println("我是客户端，服务端说：" + info);

            }

            //4.关闭资源

            br.close();

            is.close();

            pw.close();

            os.close();

            socket.close();

        } catch (UnknownHostException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

}

ServerThread.java

package com.zrl.thread;

/**

 * 服务器端线程处理类

 * @author 16114

 *

 */

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.PrintWriter;

import java.net.Socket;

public class ServerThread extends Thread {

    //和本线程相关的Socket

    Socket socket = null;

    public ServerThread(Socket socket) {

        this.socket = socket;

    }

    //线程执行的操作，响应客户端的请求

    @Override

    public void run() {

        //获取输入流，并读取客户端信息

        InputStream is=null;

        InputStreamReader isr=null;

        BufferedReader br=null;

        OutputStream os =null;

        PrintWriter pw = null;

        try {

            is = socket.getInputStream();

            isr = new InputStreamReader(is);

            br = new BufferedReader(isr);

            String info = null;

            while((info=br.readLine())!=null) {

                System.out.println("我是服务器，客户端说：" + info);

            }

            socket.shutdownInput();

            //获取输出流，响应客户端的请求

            os = socket.getOutputStream();

            pw = new PrintWriter(os); //包装为打印流

            pw.write("欢迎您！");

            pw.flush(); //调用flush将缓冲输出

        } catch (IOException e) {

            e.printStackTrace();

        }finally {//关闭相关资源

                try {

                    if(pw!=null) pw.close();

                    if(os!=null) os.close();

                    if(br!=null) br.close();

                    if(isr!=null) isr.close();

                    if(is!=null) is.close();

                    if(socket!=null) socket.close();

                } catch (IOException e) {

                    e.printStackTrace();

                }

          }

    }

}