【android】Socket简单用法

转自：http://www.cnblogs.com/harrisonpc/archive/2011/03/31/2001565.html

 Socket通常也称做”套接字“，用于描述IP地址和端口，废话不多说，它就是网络通信过程中端点的抽象表示。值得一提的是，Java在包java.net中提供了两个类Socket和ServerSocket，分别用来表示双向连接的客户端和服务端。这是两个封装得非常好的类，使用起来很方便！

    下面将首先创建一个SocketServer的类作为服务端如下，该服务端实现了多线程机制，可以在特定端口处监听多个客户请求，一旦有客户请求，Server总是会创建一个服务纯种来服务新来的客户，而自己继续监听。程序中accept()是一个阻塞函数，所谓阻塞性方法就是说该方法被调用后将等待客户的请求，直到有一个客户启动并请求连接到相同的端口，然后accept()返回一个对应于客户的Socket。这时，客户方和服务方都建立了用于通信的Socket，接下来就是由各个Socket分别打开各自的输入、输出流。

• SocketServer类，服务器实现：

package learn.test;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 SocketServer {ServerSocket sever;public SocketServer(int port) {try {sever = new ServerSocket(port);} catch (IOException e) {e.printStackTrace();}}public void beginListen() {while (true) {try {final Socket socket = sever.accept();new Thread(new Runnable() {public void run() {BufferedReader in;try {in = new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF-8"));PrintWriter out = new PrintWriter(socket.getOutputStream());while (!socket.isClosed()) {String str;str = in.readLine();out.println("Hello!world!! " + str);out.flush();if (str == null || str.equals("end"))break;System.out.println(str);}socket.close();} catch (IOException e) {e.printStackTrace();}}}).start();} catch (IOException e) {e.printStackTrace();}}}}

SocketClient类，客户端实现：

public class SocketClient {static Socket client;public SocketClient(String site, int port) {try {client = new Socket(site, port);System.out.println("Client is created! site:" + site + " port:"+ port);} catch (UnknownHostException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}public String sendMsg(String msg) {try {BufferedReader in = new BufferedReader(new InputStreamReader(client.getInputStream()));PrintWriter out = new PrintWriter(client.getOutputStream());out.println(msg);out.flush();return in.readLine();} catch (IOException e) {e.printStackTrace();}return "";}public void closeSocket() {try {client.close();} catch (IOException e) {e.printStackTrace();}}public static void main(String[] args) throws Exception {}}

 接下来就是来测试Socket通信了！

   先运行TestSocketServer类，打开服务端，在12345端口处监听！

public class TestSocketServer {public static void main(String[] argvs) {SocketServer server = new SocketServer(12345);server.beginListen();}}

再运行TestSocketClient类：

public class TestSocketClient {public static void main(String[] args) {SocketClient client = new SocketClient("127.0.0.1", 12345);System.out.println(client.sendMsg("nimei1"));client.closeSocket();SocketClient client1 = new SocketClient("127.0.0.1", 12345);System.out.println(client1.sendMsg("nimei1111"));client1.closeSocket();SocketClient client11 = new SocketClient("127.0.0.1", 12345);System.out.println(client11.sendMsg("nimei11111111"));client11.closeSocket();SocketClient client111 = new SocketClient("127.0.0.1", 12345);System.out.println(client111.sendMsg("nimei11111111111111111"));client111.closeSocket();}}

输出结果如下：

服务端：

Client is created! site:127.0.0.1 port:12345Hello!world!! nimei1Client is created! site:127.0.0.1 port:12345Hello!world!! nimei1111Client is created! site:127.0.0.1 port:12345Hello!world!! nimei11111111Client is created! site:127.0.0.1 port:12345Hello!world!! nimei11111111111111111

客户端：

nimei1nimei1111nimei11111111nimei11111111111111111