Android Socket通信编程

安卓客户端通过socket与服务器端通讯一般可以按照以下几个步骤：
（1）.通过IP地址和端口实例化Socket，请求连接服务器：
socket = new Socket(HOST, PORT); //host:为服务器的IP地址 port：为服务器的端口号
（2）.获取Socket流以进行读写，并把流包装进BufferWriter或者PrintWriter：
PrintWriter out = new PrintWriter( new BufferedWriter( new OutputStreamWriter(socket.getOutputStream())),true);

这里涉及了三个类：socket.getOutputStream得到socket的输出字节流，OutputStreamWriter是字节流向字符流转换的桥梁，BufferWriter是字符流，然后再包装进PrintWriter。

（3）对Socket进行读写
if (socket.isConnected()) {
if (!socket.isOutputShutdown()) {
out.println(msg);
}
}
（4）关闭打开的流，一定要注意对socket输入流/输出流的关闭.
out.close();

main.xml中的参考代码：

 <?xml version=＂1.0＂ encoding=＂utf-8＂?>

<LinearLayout xmlns:android=http://schemas.android.com/apk/res/android

android:orientation=＂vertical＂

android:layout_width=＂fill_parent＂

android:layout_height=＂fill_parent＂>

<TextView

android:id=＂@+id/TextView＂

android:singleLine=＂false＂

android:layout_width=＂fill_parent＂

android:layout_height=＂wrap_content＂ />

<EditText android:hint=＂content＂

android:id=＂@+id/EditText01＂

android:layout_width=＂fill_parent＂

android:layout_height=＂wrap_content＂>

</EditText>

<Button

android:text=＂send＂

android:id=＂@+id/Button01＂

android:layout_width=＂fill_parent＂

android:layout_height=＂wrap_content＂>

</Button>

</LinearLayout>

安卓客户端的源代码：

public class SocketDemo extends Activity implements Runnable {

private TextView tv_msg = null;

private EditText ed_msg = null;

private Button btn_send = null;

private static final String HOST = ＂192.168.1.150＂;

private static final int PORT = 9999;

private Socket socket = null;

private BufferedReader in = null;

private PrintWriter out = null;

private String content = ＂＂;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

tv_msg = (TextView) findViewById(R.id.TextView);

ed_msg = (EditText) findViewById(R.id.EditText01);

btn_send = (Button) findViewById(R.id.Button01);

try {

socket = new Socket(HOST, PORT);

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

out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(

socket.getOutputStream())), true);

} catch (IOException ex) {

ex.printStackTrace();

ShowDialog(＂login exception＂ + ex.getMessage());

}

btn_send.setOnClickListener(new Button.OnClickListener() {

@Override

public void onClick(View v) {

// TODO Auto-generated method stub

String msg = ed_msg.getText().toString();

if (socket.isConnected()) {

if (!socket.isOutputShutdown()) {

out.println(msg);

}

}

}

});

new Thread(SocketDemo.this).start();

}

public void ShowDialog(String msg) {

new AlertDialog.Builder(this).setTitle(＂notification＂).setMessage(msg)

.setPositiveButton(＂ok＂, new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).show();

}

public void run() {

try {

while (true) {

if (socket.isConnected()) {

if (!socket.isInputShutdown()) {

if ((content = in.readLine()) != null) {

content += ＂\n＂;

mHandler.sendMessage(mHandler.obtainMessage());

} else {

}

}

}

}

} catch (Exception e) {

e.printStackTrace();

}

}

public Handler mHandler = new Handler() {

public void handleMessage(Message msg) {

super.handleMessage(msg);

tv_msg.setText(tv_msg.getText().toString() + content);

}

};

}

服务器端得java代码：

public class Main {

private static final int PORT = 9999;

private List<Socket> mList = new ArrayList<Socket>();

private ServerSocket server = null;

private ExecutorService mExecutorService = null; //线程池

public static void main(String[] args) {

new Main();

}

public Main() {

try {

server = new ServerSocket(PORT);

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

System.out.print(＂server start ...＂);

Socket client = null;

while(true) {

client = server.accept();

mList.add(client);

mExecutorService.execute(new Service(client)); //启动一个新线程来处理连接

}

}catch (Exception e) {

e.printStackTrace();

}

}

class Service implements Runnable {

private Socket socket;

private BufferedReader in = null;

private String msg = ＂＂;

public Service(Socket socket) {

this.socket = socket;

try {

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

msg = ＂user＂ +this.socket.getInetAddress() + ＂come toal:＂

+mList.size();

this.sendmsg();

} catch (IOException e) {

e.printStackTrace();

}

}

@Override

public void run() {

// TODO Auto-generated method stub

try {

while(true) {

if((msg = in.readLine())!= null) {

if(msg.equals(＂exit＂)) {

System.out.println(＂ssssssss＂);

mList.remove(socket);

in.close();

msg = ＂user:＂ + socket.getInetAddress()

+ ＂exit total:＂ + mList.size();

socket.close();

this.sendmsg();

break;

} else {

msg = socket.getInetAddress() + ＂:＂ + msg;

this.sendmsg();

}

}

}

} catch (Exception e) {

e.printStackTrace();

}

}

public void sendmsg() {

System.out.println(msg);

int num =mList.size();

for (int i = 0; i < num; i++) {

Socket mSocket = mList.get(index);

PrintWriter pout = null;

try {

pout = new PrintWriter(new BufferedWriter(

new OutputStreamWriter(mSocket.getOutputStream())),true);

pout.println(msg);

}catch (IOException e) {

e.printStackTrace();

}

}

}

}

}