java socket编程，客户端发出检索字段，服务端查询数据并返回结果集

1.服务器端

/**

 * 

 */

import java.io.*;

import java.net.*;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.*;

import java.util.concurrent.*;

import com.mysql.jdbc.PreparedStatement;

/**

 * @author linzhifeng

 *

 */

public class Server{
//服务器端 需要单独编译并在命令行模式下启动测试 
public static final String DBDRIVER = "com.mysql.jdbc.Driver";
public static final String DBURL = "jdbc:mysql://localhost:3306/jdbc";
public static final String DBUSER = "root";
public static final String DBPASSWORD = "123456";

    private static final int SERVERPORT = 54323; //服务器端口  

    private static List<Socket> mClientList = new ArrayList<Socket>(); //客户端连接 通过List来储存所有连接进来的客户端的Socket对象(也可用CopyOnWriteArrayList来储存) 

    private ExecutorService mExecutorService;  //线程池 需要为每个客户端都开启一个线程    

    private ServerSocket mServerSocket;  //ServerSocket对象  

    public static void main(String[] args){ //main方法 开启服务器

     new Server();

    }

    public Server(){

     try{   

      mServerSocket = new ServerSocket(SERVERPORT);//设置服务器端口   

      mExecutorService = Executors.newCachedThreadPool();//创建一个线程池

      System.out.println("start...");   

      Socket client = null;//用来临时保存客户端连接的Socket对象

      while (true){    

       client = mServerSocket.accept(); //接收客户连接并添加到list中

       mClientList.add(client);    

       mExecutorService.execute(new ThreadServer(client));//开启一个客户端线程

      }

     }catch (IOException e){

      e.printStackTrace();

     }

    } 

    static class ThreadServer implements Runnable{//每个客户端单独开启一个线程

        private Socket   mSocket;

        private BufferedReader mBufferedReader;

        private PrintWriter  mPrintWriter;

        private String   mStrMSG;

        public ThreadServer(Socket socket) throws IOException{

         this.mSocket = socket;

         mBufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));

         mStrMSG = "user:"+this.mSocket.getInetAddress()+" come total:" + mClientList.size();

         sendMessage();

        }

        public void run(){

         try{

          while ((mStrMSG = mBufferedReader.readLine()) != null){

           if (mStrMSG.trim().equals("exit")){

            //当一个客户端退出时

            mClientList.remove(mSocket);

            mBufferedReader.close();

            mPrintWriter.close();

            mStrMSG = "user:"+this.mSocket.getInetAddress()+" exit total:" + mClientList.size();

            mSocket.close();

            sendMessage();

            break;

           }else{
String name=mStrMSG;

            mStrMSG = mSocket.getInetAddress() + ":" + mStrMSG;

            Connection con = null;

     try {
Class.forName(DBDRIVER);
con = DriverManager.getConnection(DBURL, DBUSER, DBPASSWORD);
     Statement str = con.createStatement();
     //String name="china";
     String sql = "select id from test where country = '"+name+"' limit 0,10";
     PreparedStatement st = (PreparedStatement) con.prepareStatement(sql);  
            java.sql.ResultSet rs=null;
     rs = st.executeQuery(sql); 
              
            while(rs.next()){  
            
System.out.println(rs.getString("id"));
            
mStrMSG+="|"+rs.getString("id");
            } 
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

    

            sendMessage();

           }

          }

         }catch (IOException e){

          e.printStackTrace();

         }

        }  

        private void sendMessage() throws IOException{//发送消息给所有客户端

         System.out.println(mStrMSG);

         for (Socket client : mClientList){

          mPrintWriter = new PrintWriter(client.getOutputStream(), true);

          mPrintWriter.println(mStrMSG);

         }

        }

       }

      }

2.客户端

/**

 * 

 */

package HTTP;

import java.io.*;

import java.net.Socket;

import java.util.concurrent.*;

/**

 * @author linzhifeng

 *

 */

public class client{//需要单独编译并在命令行模式下启动测试

    private static final int  PORT = 54323;

    private static ExecutorService exec = Executors.newCachedThreadPool();

    public static void main(String[] args) throws Exception{

     new client();

    }

    public client(){

     try{

      Socket socket = new Socket("127.0.0.1", PORT);

      exec.execute(new Sender(socket));

      BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));

      String msg;

      while ((msg = br.readLine()) != null){

       System.out.println(msg);

      }

     }catch (Exception e){

     }

    }     

    static class Sender implements Runnable{//客户端线程获取控制台输入消息

     private Socket socket;

     public Sender(Socket socket){

      this.socket = socket;

     }

     public void run(){

      try{

       BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

       PrintWriter pw = new PrintWriter(socket.getOutputStream(), true);

       String msg;

       while (true){

        msg = br.readLine();

        pw.println(msg);

        if (msg.trim().equals("exit")){

         pw.close();

         br.close();

         exec.shutdownNow();<
4000
br />
         break;

        }

       }

      }catch (Exception e){

       e.printStackTrace();

      }

     }

    }  

   }

3.cmd下编译运行服务器

javac -cp mysql-connector-java-5.0.8-bin.jar ./Server.java

java -cp mysql-connector-java-5.0.8-bin.jar Server