TCP服务端和客户端(Java)

TCP服务端源码示例：

package TCP;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class TCPServer{

    public static void main(String[] args) {
        ServerSocket ss=null;
        Socket s=null;
        BufferedReader br=null;
        PrintWriter pw=null;
        try {
            ss=new ServerSocket(7888);
            System.out.println("Server is running on port 7888...");
            int i=0;
            while (true) {
                s = ss.accept();
                br=new BufferedReader(new InputStreamReader(s.getInputStream()));
                i++;
                String str=br.readLine();
                System.out.println("You are No."+i+" guest, and your IP is:"+s.getInetAddress()+" "+str);
                str=str.toUpperCase();
                pw = new PrintWriter(s.getOutputStream());
                pw.println(str);
                pw.flush();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if(pw!=null) pw.close();
            if(br!=null)try{br.close();}catch(IOException e){}
            if(s!=null)try{s.close();}catch(IOException e){}
            if(ss!=null)try{ss.close();}catch(IOException e){}
        }
    }

}

TCP客户端源码示例：

package TCP;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;

public class TCPClient {
    public static void main(String[] args) {
        Socket s=null;
        BufferedReader br=null;
        BufferedReader brin=null;
        PrintWriter pw=null;
  
        try {
            s=new Socket("127.0.0.1",7888);
            System.out.println("Please enter something:");
            brin=new BufferedReader(new InputStreamReader(System.in));
            String strin = brin.readLine();
            pw = new PrintWriter(s.getOutputStream());
            pw.println(strin);
            pw.flush();
            br = new BufferedReader(new InputStreamReader(s.getInputStream()));
            String str = br.readLine();
            System.out.println(str);

        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if(pw!=null) pw.close();
            if(brin!=null)try{brin.close();}catch(IOException e){}
            if(br!=null)try{br.close();}catch(IOException e){}
            if(s!=null)try{s.close();}catch(IOException e){}
        }
    }

}

另：指定字符编码示例：

   String strTest = "TCP测试";
   byte[] bTest = strTest.getBytes("UTF-8");
   s.getOutputStream().write(bTest);
   s.getOutputStream().flush();
   byte[] bRst = new byte[1024];
   s.getInputStream().read(bRst);
   String str = new String(bRst,"UTF-8");
   System.out.println(str);