Socket

通信过程

协议TCP

1.transfer control protocal,传输控制协议
2：必须先建立连接
3：安全协议
4:有序

UDP与TCP

应用场合

1：进程间通信
2：API
ServerSocket //服务器端套接字
Socket //套接字
3：协议
//数据格式：
TCP //传输控制协议，面向连接，基于流的
UDP //用户数据包协议，无连接的
IP //Internet procatl,
FTP //file transfer prorocal
SMTP //simple main transfer protocal
http //超文本传输协议
4:
单工：有去无回
半双工：不能同时进行收发
全双工：能同时进行收发

一：实现连接

Socket

package fanyongjun.Socket;
import java.net.Socket;
public class SocketDemo {
 public static void main(String[] args) throws Exception {
  Socket sock=new Socket("localhost",9999);
  System.out.println("local:"+sock.getLocalPort());
  System.out.println("port:"+sock.getPort());
  
while(true) {
 Thread.sleep(1000);
}
 }
}

ServerSocket

package fanyongjun.Socket;
import java.net.ServerSocket;
import java.net.Socket;
public class ServerSocketDemo {
public static void main(String[] args) throws Exception {
 //创建ServerSocket对象
 ServerSocket ss=new ServerSocket(9999);
 //System.out.println(ss.getLocalPort());
 //接收
 while(true) {
 Socket sock=ss.accept();
 System.out.println("localport:"+sock.getLocalPort());
 System.out.println("port:"+sock.getPort());
 } 
}
}

在socket中简单通信

MySocket

public class MyScoket {
public static void main(String[] args) throws Exception, Exception {
 Socket socket =new Socket("localhost",8888);
 OutputStream os=socket.getOutputStream();
 InputStream is=socket.getInputStream();
 //主动向服务器发送一条消息
 os.write("hello world".getBytes());
 byte []buffer=new byte[1024];  
 int len=-1;
 while((len=is.read(buffer))!=-1) {
  String msg=new String(buffer,0,len);
  System.out.println("收到回执："+msg);
  os.write(("from client"+msg).getBytes());
 Thread.sleep(500);
 }
 os.close();
 socket.close();
}
}

MyServerSocket

package fanyongjun.socket;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
/**
 * 服务器端
 * @author Frenzy Fan
 *
 */
public class MyServerSocket {
public static void main(String[] args) throws Exception {
 //创建服务器 Socket
 ServerSocket ss=new ServerSocket(8888);
 //接受连接请求
 Socket  s=ss.accept();
 System.out.println("有人连进来了");
 //得到输入流，读取客户端的请求数据
 InputStream is=s.getInputStream();
 OutputStream os=s.getOutputStream();
 byte []bytes=new byte[1024]; 
 int len=-1;
 while((len=is.read(bytes))!=-1) {
 System.out.println("收到消息"+new String(bytes,0,len));
 String msg="From sever:"+new String(bytes,0,len);
 os.write(msg.getBytes());
}
System.out.println("流关闭了！");
is.close();
s.close();
ss.close();
}
}

在socket中1-1通信

MySocket

package fanyongjun.socket2;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.Socket;
public class Myscoket {
public static void main(String[] args) throws Exception, Exception {
 //创建socket对象
 Socket socket =new Socket("localhost",8888);
 OutputStream os=socket.getOutputStream();
 //缓冲区服务器
 BufferedReader bis=new BufferedReader(new InputStreamReader(System.in));
 String line=null;
 while(true) {
  line=bis.readLine();
  if(line!=null&&"exit".equals(line)) {
   break ;
  }
  if(line!=null) {
   os.write(line.getBytes());
  }
 }
 os.close();
 socket.close();
}
}

MyServerSocket

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
/**
 * 服务器端
 * @author Frenzy Fan
 *
 */
public class MyServerSocket {
public static void main(String[] args) throws Exception {
 //创建服务器 Socket
 ServerSocket ss=new ServerSocket(8888);
 //接受连接请求
 Socket  s=ss.accept();
 System.out.println("有人连进来了");
 //得到输入流，读取客户端的请求数据
 InputStream is=s.getInputStream();
 byte []bytes=new byte[1024]; 
 int len=-1;
 while((len=is.read(bytes))!=-1) {
 System.out.println("收到消息"+new String(bytes,0,len));
 String msg="From sever:"+new String(bytes,0,len);
}
System.out.println("流关闭了！");
is.close();
s.close();
ss.close();
}
}

socket中多对一通信

MySocket

package fanyongjun.socket3.copy;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.Socket;
public class Myscoket {
public static void main(String[] args) throws Exception, Exception {
 //创建socket对象
 Socket socket =new Socket("localhost",8888);
 OutputStream os=socket.getOutputStream();
 //缓冲区服务器
 BufferedReader bis=new BufferedReader(new InputStreamReader(System.in));
 String line=null;
 while(true) {
  line=bis.readLine();
  if(line!=null&&"exit".equals(line)) {
   break ;
  }
  if(line!=null) {
   os.write(line.getBytes());
  }
 }
 os.close();
 socket.close();
}
}

MyServerSocket

package fanyongjun.socket3.copy;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
/**
 * 服务器端
 * @author Frenzy Fan
 *
 */
public class MyServerSocket {
public static void main(String[] args) throws Exception {
 //创建服务器 Socket
 ServerSocket ss=new ServerSocket(8888);
 System.out.println("服务器启动了");
 //接受连接请求
 while(true) {
 Socket  s=ss.accept();
 new SessionThread(s).start();;
 }
 }
}

SessionThread

package fanyongjun.socket3.copy;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
public class SessionThread extends Thread {
private Socket socket;
private String descStr;
public SessionThread(Socket socket) {
 this.socket=socket;
}
public void run() {
 try {
  //返回远端的ip地址
  InetAddress addr=socket.getInetAddress();
  //远程主机名
  String hostname=addr.getHostName();
  //返回远端的端口号
  int port= socket.getPort();
  descStr = "{"+hostname+":"+port+"}";
  System.out.println(descStr+"上线了");
  OutputStream os=socket.getOutputStream();
  //in
  InputStream is=socket.getInputStream();
  //
  byte[]buffer=new byte[1024];
  int len=-1;
  while((len=is.read(buffer))!=-1){
   System.out.println(descStr+"说:"+new String(buffer,0,len));
   //System.out.println();
   //把消息回传给客户端
   //os.write(buffer,0,len);
  }
System.out.println(descStr+"下线了");
 } catch (IOException e) {
  System.out.println(descStr+"异常下线了");
  e.printStackTrace();
 }
}
}