要开发TCP/UDP通讯的程序，下面这两段代码，分别介绍了TCP/UCP通过的一个实例：
代码一：
private void tcpdata() {
try {
Socket s = new Socket("192.168.0.25", 65500);
// outgoing stream redirect to socket
OutputStream out = s.getOutputStream();
// 注意第二个参数据为true将会自动flush，否则需要需要手动操作out.flush()
PrintWriter output = new PrintWriter(out, true);
output.println("Hello IdeasAndroid! 伪IP为："
+ SIMCardToIP("13512345006"));
InputStream inputStream = s.getInputStream();
DataInputStream input = new DataInputStream(inputStream);
byte[] b = new byte[10000];
int length = input.read(b);
inputReader = new InputStreamReader(inputStream);
String Msg = new String(b, 0, length, "gb2312");
Toast.makeText(TcpTest.this, Msg, 1000).show();
Log.d("Tcp Demo", "message From Server:" + Msg);
s.close();
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
下面的代码是UDP通讯的过程：
public String send(String msg) {
StringBuilder sb = new StringBuilder();
InetAddress local = null;
try {
local = InetAddress.getByName("192.168.0.25"); // 本机测试
} catch (UnknownHostException e) {
e.printStackTrace();
}
try {
dSocket = new DatagramSocket(); // 注意此处要先在配置文件里设置权限,否则会抛权限不足的异常
} catch (SocketException e) {
e.printStackTrace();
}
int msg_len = msg == null ? 0 : msg.length();
DatagramPacket dPacket = new DatagramPacket(msg.getBytes(), msg_len,
local, SERVER_PORT);
try {
dSocket.send(dPacket);
} catch (IOException e) {
e.printStackTrace();
}
try {
dSocket.receive(dPacket);
sb.append(new String(dPacket.getData()));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
dSocket.close();
return sb.toString();
}