寻求简单通讯的例子
     要求tcp/ip同步短连接 
 即: 
                客户端发送信息时连接,得到服务响应(信息的返回,问题的回答等等)客户端中止连接。 
 再发送时重新连接。     
 -----------------告急--------------
------解决方案--------------------服务端:   
 import java.io.DataInputStream; 
 import java.io.DataOutputStream; 
 import 
java.io.IOException; 
 import java.net.ServerSocket; 
 import java.net.Socket;   
 public class SimpleTestServer { 
 	public static void main(String[] args) { 
 		try { 
 			ServerSocket ssocket = new ServerSocket(2000); 
                                                                 //port 
 			while (true) { 
 				Socket socket = ssocket.accept(); 
 				socket.setSoTimeout(0); 
 				DataInputStream dataIn = new DataInputStream(socket 
 						.getInputStream()); 
 				byte[] readBytes = new byte[1000]; 
 				int length = dataIn.read(readBytes); 
 				if (length == -1) { 
 					break; 
 				} 
 				/** 
 				 * 处理请求,比如打印收到的信息。 
 				 */ 
 				System.out.println(new String(readBytes,0,length)); 
 				/** 
 				 * 构造应答信息 
 				 */ 
 				byte[] reply = new byte[] {  'r ',  'e ',  'p ',  'l ',  'y ' }; 
 				DataOutputStream dataOut = new DataOutputStream(socket 
 						.getOutputStream()); 
 				/** 
 				 * 发送应答信息 
 				 */ 
 				dataOut.write(reply); 
 				dataOut.flush(); 
 				dataOut.close(); 
 				/** 
 				 * 关闭连接 
 				 */ 
 				socket.close(); 
 			} 
 		} catch (
IOException e) { 
 			e.printStackTrace(); 
 		} 
 	} 
 }   
 客户端: 
 import java.io.DataInputStream; 
 import java.io.DataOutputStream; 
 import java.io.IOException; 
 import java.net.Socket;   
 public class SimpleTestClient { 
 	public static void main(String[] args) { 
 		try 
 		{ 
 			Socket socket = new Socket( "127.0.0.1 ",2000); 
                                                     //ip       port 
 			socket.setSoTimeout(0); 
 			DataOutputStream dataOut = new DataOutputStream(socket 
 					.getOutputStream()); 
 			byte[] requestBytes=new byte[]{ 'r ', 'e ', 'q ', 'u ', 'e ', 's ', 't '}; 
 			dataOut.write(requestBytes); 
 			dataOut.flush(); 
 			DataInputStream dataIn = new DataInputStream(socket 
 					.getInputStream()); 
 			byte[] readBytes = new byte[1000]; 
 			int length = dataIn.read(readBytes); 
 			dataIn.close(); 
 			if(length==-1) 
 			{ 
 				dataOut.close(); 
 				socket.close(); 
 			} 
 			System.out.println(new String(readBytes,0,length)); 
 			dataOut.close(); 
 			socket.close(); 
 		}catch(IOException e) 
 		{ 
 			e.printStackTrace(); 
 		} 
 	} 
 }