day 020 udp

TOMCAT

8080默认端口

启动start.bat,默认会找到webapps中的文件，访问TOOT中的index.html默认

client 和server

客户端和服务端

客户端创建Socket new Socket(InetAddress,port)

连接上之后创建输出流 socket.getOutoutStream

os.write(bytes) 字节输出数据

服务端创建服务

ServerSocket (port)指定端口

连接上后监听获取socket = serverSocket.accpt()

获取输入流，读取流中数据 ，outputstram输出流写出

udp双向的不存在客户端服务端

DataGramPackt 发送包

DataGramSocket 接收包

• UDPreceive

• package com.udp;
  
  import java.net.DatagramPacket;
  import java.net.DatagramSocket;
  import java.net.SocketException;
  
  /**
   * @ Author     ：wwwzhqwww
   * @ Date       ：Created in 17:22 2021/1/24
   * @ Description：接收udp
   * @ Modified By：
   * @Version: $version$
   */
  public class UdpReceive {
      public static void main(String[] args) {
          DatagramSocket socket = null;
          try {
              socket = new DatagramSocket(9999);
              while (true){
                  byte[] bytes = new byte[600];
                  DatagramPacket packet = new DatagramPacket(bytes,0,bytes.length);//此处大小需要注意，当发送的行字符超出bytes的长度，，内容将丢失
                  socket.receive(packet);
                  System.out.println(packet.getData().length+"******packet.getdata.length");
                  System.out.println(packet.getLength()+"******packet.getlength");
                  String str = new String(packet.getData(),0,packet.getLength());
                  System.out.println(str);
                  if ("bye".equals(str)){
                      break;
                  }
              }
          } catch ( Exception e) {
              e.printStackTrace();
          }finally {
              if (socket!=null){
                  socket.close();
              }
          }
  
  
  //        DatagramPacket packet;
  //        DatagramSocket socket = null;
  //        int port = 6666;
  //        try {
  //            socket = new DatagramSocket(port);
  //
  //            while (true){
  //                byte[] bytes = new byte[600];
  //                packet = new DatagramPacket(bytes,0,bytes.length);
  //                socket.receive(packet);
  //                byte[] data = packet.getData();
  //                String msg = new String(data,0, data.length);
  //                System.out.println(msg);
  //                if (msg.equals("bye")){
  //                    break;
  //                }
  //            }
  //
  //        } catch (Exception e) {
  //            e.printStackTrace();
  //        }finally {
  //            if (socket!=null){
  //                socket.close();
  //            }
  //
  //        }
  
      }
  }
  

• udp send

• package com.udp;
  
  import java.io.BufferedReader;
  import java.io.InputStreamReader;
  import java.net.DatagramPacket;
  import java.net.DatagramSocket;
  import java.net.InetAddress;
  
  /**
   * @ Author     ：wwwzhqwww
   * @ Date       ：Created in 17:22 2021/1/24
   * @ Description：发送udp
   * @ Modified By：
   * @Version: $version$
   */
  public class UdpSend {
      public static void main(String[] args) {
          DatagramSocket socket =null;
          try {
              socket = new DatagramSocket(8888);
              while (true){
                  BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
                  String msg = br.readLine();
                  byte[] bytes = msg.getBytes();
                  DatagramPacket packet = new DatagramPacket(bytes,0,bytes.length,InetAddress.getByName("localhost"),9999);
                  socket.send(packet);
                  if ("bye".equals(msg)){
                      break;
                  }
              }
  
          } catch (Exception e) {
              e.printStackTrace();
          }finally {
              if (socket!=null){
                  socket.close();
              }
  
          }
  
  
  //        DatagramSocket socket = null;
  //        DatagramPacket packet;
  //        InetAddress ia ;
  //        int port = 8888;
  //        String msg;
  //
  //        {
  //            try {
  //                ia= InetAddress.getByName("127.0.0.1");
  //                socket = new DatagramSocket(port);
  //                while (true) {
  //                    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  //                    msg = br.readLine();
  //                    byte[] datas = msg.getBytes();
  //                    packet = new DatagramPacket(datas,0,datas.length,ia,6666);
  //                    socket.send(packet);
  //                    if (msg.equals("bye")){
  //                        br.close();
  //                        break;
  //                    }
  //                }
  //
  //            } catch ( Exception e) {
  //                e.printStackTrace();
  //            }finally {
  //                socket.close();
  //            }
  //        }
      }
      
  }