androidsocket通信建立

接收端：

protected static final int SendPort = 8600;
protected static final int ReceivePort = 8601;
private MulticastSocket socket;
private InetAddress address;
private DatagramPacket packet;

socket = new MulticastSocket(ReceivePort);
address = InetAddress.getByName("224.0.0.1");
socket.joinGroup(address);


private Runnable mSendRunnable = new Runnable() {
public void run() {
//发送数据包,寻找接收端
byte[] buf = "SMART IR".getBytes();
packet = new DatagramPacket(buf, buf.length, address, SendPort);
try {
socket.send(packet);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
};

接收端:

public class IRReceiveSetupConnectSocket {
protected static final String TAG = "MultiSocketA";
protected static final int SendPort = 8601;
protected static final int ReceivePort = 8600;
private MulticastSocket socket;
private InetAddress address;
private boolean mReceiveMultiSocket = true;
private int ipaddr;
public IRReceiveSetupConnectSocket(int ip) throws IOException{
ipaddr = ip;
socket = new MulticastSocket(ReceivePort);
address = InetAddress.getByName("224.0.0.1");
socket.joinGroup(address);

new Thread(run).start();

}

// 此thread会一直poll multisovket的信息，只要有接受到信息，就将自己ip地址广播出去；发送端可以以此地址发送key（其它线程的socket）
Runnable run = new Runnable() {
@Override
public void run() {
while(mReceiveMultiSocket)
{
byte[] rev = new byte[128];
DatagramPacket packet = new DatagramPacket(rev, rev.length);
try {
Log.d("yanxi", "MultiSocket Waitting.......");

//receive connect requst,and send ipaddr to request host
socket.receive(packet);
Log.d("yanxi", "MultiSocket received........"+ new String(packet.getData()).trim());
//send ipaddr to request host
byte[] buf = (""+ipaddr).getBytes();
packet = new DatagramPacket(buf, buf.length, address, SendPort);
socket.send(packet);
Log.d("yanxi", "MultiSocket send........"+ ipaddr);
//mReceiveMultiSocket = false;
try {
Thread.sleep(100);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
};

}
  通过以上实现发送端就能得到接收端的IP，从而为后面的发送IR Code做基础