服務端

package com.hmsm.socket.server;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * 模擬查詢天氣
 * Socket 服務端
 * @author Administrator
 *
 */
public class SocketServer {
	public static void
 
 main(String[] args) throws IOException {
		
        //啟動socket服務端
		ServerSocket serverSocket=new ServerSocket(55555);
		System.out.println("服務端已啟動。。。");
		DataInputStream inputStream=null;
		DataOutputStream outputStream=null;
		while(true){
			try {
			//監聽客戶端連線 accept()是阻塞方法
			Socket socket=  serverSocket.accept();
			
			//先接收從客戶端傳送過來的資料
 

			inputStream=new DataInputStream(socket.getInputStream()) ;
			 //城市名稱
			 String cityName=inputStream.readUTF();
			 //接收客戶端傳送過來的城市名稱
			 System.out.println("from client。。。"+cityName);
			
			
			//再通過服務端傳送出去
			outputStream=new DataOutputStream(socket.getOutputStream());
		        String result="晴轉陰"
 
;
			 //將查詢結果傳送出去
			 outputStream.writeUTF(result);
			 System.out.println("to client。。。"+result);
			} catch (Exception e) {
				e.printStackTrace();
			}finally{
				if(inputStream!=null){
					inputStream.close();
				}
				if(outputStream!=null){
					outputStream.close();
				}
			}
		}
		
	}
}

客戶端

package com.hmsm.socket.client;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;

/**
* 模擬查詢天氣
* Socket 客戶端
* @author Administrator
*
*/
public class SocketClient {
    public static void main(String[] args) throws UnknownHostException, IOException {
    	//建立Socket連線
    	Socket socket=new Socket("127.0.0.1",55555);
    	
    	
    	DataInputStream inputStream=null;
    	DataOutputStream outputStream=null;
    	try {
    		//傳送資料
    		 outputStream=new DataOutputStream(socket.getOutputStream());
    		String cityName="成都";
    		outputStream.writeUTF(cityName);
    		System.out.println("to server。。。"+cityName);
    		
    		
    		//接收資料
    		 inputStream=new DataInputStream(socket.getInputStream());
    		String result=inputStream.readUTF();
    		System.out.println("from server。。。"+result);
    		
    	} catch (Exception e) {
    		e.printStackTrace();
    	}finally{
    		if(outputStream!=null){
    			outputStream.close();
    		}
    		if(inputStream!=null){
    			inputStream.close();
    		}
    		if(socket!=null){
    			socket.close();
    		}
    	}
    }
}