Java面试知识点：网络编程

超、凢脫俗 2022-09-10 05:16 202阅读 0赞

# 问题：Java面试知识点：网络编程 #

# 答案： #

1.InetAddress

代码如下:

package com.xy;
    
    import java.net.InetAddress;
    import java.net.UnknownHostException;
    
    /**
     * @ProjectName: day01
     * @Package: com.xy
     * @ClassName: test01
     * @Author: 杨路恒
     * @Description:
     * @Date: 2021/9/1 0001 11:31
     * @Version: 1.0
     */
    public class test01 {
        public static void main(String[] args) throws UnknownHostException {
            InetAddress name = InetAddress.getByName("WIN-S5E6V36PP3P");
            String hostAddress = name.getHostAddress();
            String hostName = name.getHostName();
            System.out.println(name);
            System.out.println(hostName);
            System.out.println(hostAddress);
    
        }
    }

2.UDP

![watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAeWFuZzEzNTYzNzU4MTI4_size_20_color_FFFFFF_t_70_g_se_x_16][]

代码如下：

package com.xy;
    
    import java.io.IOException;
    import java.net.*;
    
    /**
     * @ProjectName: day01
     * @Package: com.xy
     * @ClassName: test02
     * @Author: 杨路恒
     * @Description:
     * @Date: 2021/9/1 0001 11:39
     * @Version: 1.0
     */
    public class test02 {
        public static void main(String[] args) throws IOException {
            DatagramSocket ds=new DatagramSocket();
            byte[] bytes="杨大大".getBytes();
            int length=bytes.length;
            InetAddress address = InetAddress.getByName("192.168.65.1");
    //        InetAddress address = InetAddress.getByName("127.0.0.1");
            int port=10086;
            DatagramPacket dp=new DatagramPacket(bytes,length,address,port);
            ds.send(dp);
            ds.close();
    
        }
    }
    
    
    
    
    
    
    
    public static void main(String[] args) throws IOException {
            DatagramSocket ds=new DatagramSocket(10086);
            byte[] bytes=new byte[1024];
            DatagramPacket dp=new DatagramPacket(bytes,bytes.length);
            ds.receive(dp);
            byte[] data = dp.getData();
            int length=dp.getLength();
            String s=new String(data,0,length);
            System.out.println(s);
            ds.close();
        }
    
    
    
    
    
    public static void main(String[] args) throws IOException {
            DatagramSocket ds=new DatagramSocket(666);
            byte[] bytes=null;
            DatagramPacket dp=null;
            while (true) {
                bytes=new byte[1024];
                dp=new DatagramPacket(bytes,bytes.length);
                ds.receive(dp);
                byte[] data = dp.getData();
                String s=new String(data,0,data.length);
                if (s.equals("886")){
                    break;
                }
                System.out.println(s);
            }
            ds.close();
        }

3.TCP

![watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAeWFuZzEzNTYzNzU4MTI4_size_20_color_FFFFFF_t_70_g_se_x_16 1][]

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代码如下：

package com.xy;
    
    import java.io.IOException;
    import java.io.OutputStream;
    import java.net.InetAddress;
    import java.net.Socket;
    
    /**
     * @ProjectName: day01
     * @Package: com.xy
     * @ClassName: test06
     * @Author: 杨路恒
     * @Description:
     * @Date: 2021/9/1 0001 21:33
     * @Version: 1.0
     */
    
    
    客户端
    
    
    public class test06 {
        public static void main(String[] args) throws IOException {
    //        Socket s=new Socket(InetAddress.getByName("192.168.65.1"),66);
            Socket s=new Socket("192.168.65.1",66);
            OutputStream os = s.getOutputStream();
            os.write("杨大大".getBytes());
            s.close();
        }
    }
    
    
    
    
    服务器端
    
    public static void main(String[] args) throws IOException {
            ServerSocket ss=new ServerSocket(66);
            Socket s = ss.accept();
            InputStream is = s.getInputStream();
            byte[] bytes=new byte[1024];
            int length = is.read(bytes);
            String s1=new String(bytes,0,length);
            System.out.println(s1);
            ss.close();
            s.close();
        }

文件上传代码如下：

package com.xy;
    
    import java.io.*;
    import java.net.Socket;
    
    /**
     * @ProjectName: day01
     * @Package: com.xy
     * @ClassName: test11Socket
     * @Author: 杨路恒
     * @Description:
     * @Date: 2021/9/2 0002 20:03
     * @Version: 1.0
     */
    public class test11Socket {
        public static void main(String[] args) throws IOException {
            Socket s=new Socket("192.168.65.1",66);
            BufferedReader br=new BufferedReader(
                    new FileReader("day09\\aa.txt"));
            OutputStream os = s.getOutputStream();
            BufferedWriter bw=new BufferedWriter(new OutputStreamWriter(os));
            String length=null;
            while ((length=br.readLine())!=null){
                bw.write(length);
                bw.newLine();
                bw.flush();
            }
    
    //        bw.write("886");
    //        bw.newLine();
    //        bw.flush();
            s.shutdownOutput();
            BufferedReader br1=new BufferedReader(
                    new InputStreamReader(s.getInputStream()));
            String s1 = br1.readLine();
            System.out.println(s1);
            br.close();
            s.close();
        }
    }
    
    
    
    
    package com.xy;
    
    import java.io.*;
    import java.net.ServerSocket;
    import java.net.Socket;
    
    /**
     * @ProjectName: day01
     * @Package: com.xy
     * @ClassName: test12Socket
     * @Author: 杨路恒
     * @Description:
     * @Date: 2021/9/2 0002 20:08
     * @Version: 1.0
     */
    public class test12Socket {
        public static void main(String[] args) throws IOException {
            ServerSocket ss=new ServerSocket(66);
            Socket s = ss.accept();
            BufferedReader br=new BufferedReader(
                    new InputStreamReader(s.getInputStream()));
            BufferedWriter bw=new BufferedWriter(
                    new FileWriter("day09\\aaa.txt"));
            String length=null;
            while ((length=br.readLine())!=null){
    //            if (length.equals("886")){
    //                break;
    //            }
                bw.write(length);
                bw.newLine();
                bw.flush();
            }
            BufferedWriter bw1=new BufferedWriter(
                    new OutputStreamWriter(s.getOutputStream()));
            bw1.write("上传成功");
            bw1.newLine();
            bw1.flush();
    
            ss.close();
    
        }
    }
    
    
    
    public static void main(String[] args) throws IOException {
            ServerSocket ss=new ServerSocket(66);
            UUID uuid=UUID.randomUUID();
            System.out.println(uuid);
            while (true){
                Socket s = ss.accept();
                new Thread(new ServerThread(s)).start();
            }
        }
    
    
    
    public class ServerThread implements Runnable{
        private Socket s;
    
        public ServerThread(Socket s) {
            this.s = s;
        }
    
        @Override
        public void run() {
            try {
                BufferedReader br=new BufferedReader(
                        new InputStreamReader(s.getInputStream()));
                int count=0;
                File file=new File("day09\\aaa[+"+count+"].txt");
                while (file.exists()){
                    count++;
                    file=new File("day09\\aaa[+"+count+"].txt");
                }
                BufferedWriter bw=new BufferedWriter(
                        new FileWriter(file));
                String length=null;
                while ((length=br.readLine())!=null){
        //            if (length.equals("886")){
        //                break;
        //            }
                    bw.write(length);
                    bw.newLine();
                    bw.flush();
                }
                BufferedWriter bw1=new BufferedWriter(
                        new OutputStreamWriter(s.getOutputStream()));
                bw1.write("上传成功");
                bw1.newLine();
                bw1.flush();
                s.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

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