Android模拟器与本地服务器的socket通讯

要注意的问题：

• IP是10.0.2.2，而不是localhost或者127.0.0.1。因为localhost或者127.0.0.1是模拟器自己。
• 注意你是否在AndroidManifest.xml里添加了permission：<uses-permission android:name=”android.permission.INTERNET” />
• 不能在主线程里建立socket连接，建议创建一个新的线程。（本人的解决方法，欢迎讨论）

import java.io.*;import java.net.*;import java.util.Date;public class Server {public static int PORT = 6688;public void run(){ServerSocket listener;try{listener = new ServerSocket(PORT);while(true){System.out.println("The server is running ...");Socket s = listener.accept();InputStream is = s.getInputStream();OutputStream os = s.getOutputStream();service(is,os);s.close();System.out.println("The server is close.");}} catch(Exception e){System.out.println(e);}}public void service(InputStream is,OutputStream os) throws IOException, UnknownHostException{DataInputStream ins = new DataInputStream(is);DataOutputStream ous = new DataOutputStream(os);String input = ins.readUTF();System.out.println(input);ous.writeUTF("The message is received");}public static void main(String[] args){Server s = new Server();s.run();}}

客户端

import java.io.*;import java.net.*;import android.os.Bundle;import android.app.Activity;import android.view.Menu;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.EditText;import android.widget.Toast;public class MainActivity extends Activity {EditText et1,et2;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);et1=((EditText)findViewById(R.id.editText1));et2=((EditText)findViewById(R.id.editText2));((Button)findViewById(R.id.button1)).setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {(new Thread(new Runnable() {       public void run() {       client();       }})).start();}});}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.activity_main, menu);return true;}public void client(){try{Socket s = new Socket("10.0.2.2",6688);DataOutputStream dos = new DataOutputStream(s.getOutputStream());DataInputStream dis = new DataInputStream(s.getInputStream());dos.writeUTF("Hello from client.");String input = dis.readUTF();runOnUiThread(new Runnable() {public void run() {Toast.makeText(getApplicationContext(), input, Toast.LENGTH_LONG).show();}});}catch (Exception e){e.printStackTrace();}}}