最近在做车联网使用UDP和车载端进行数据交互，网上找了很多UDP数据发送和接收的居然都不成功，（可发送接收不到数据）。
重点是DatagramPacket发送和接收的不能使用同一个。
附上代码：
public class UdpSocket {
private DatagramSocket socket;
public static final int UDPPORT = 8888;
private Handler handler;
private boolean getMessage;
public UdpSocket(Handler handler) throws SocketException {
this.handler = handler;
getMessage = true;
if (socket == null) {
socket = new DatagramSocket(UDPPORT);
}
}
byte data[] = new byte[1024];
public void initSocket() {
ExecutorUtil.execute(new Runnable() {
@Override
public void run() {
try {
DatagramPacket datagramPackage = new DatagramPacket(data, data.length);
while (true) {
socket.receive(datagramPackage);
// LogUtils.e("UdpSocket1"+ new String(datagramPackage.getData(), datagramPackage.getOffset(), datagramPackage.getLength()));
//接收到的byte[]
byte[] m = Arrays.copyOf(datagramPackage.getData(), datagramPackage.getLength());
LogUtils.e("UdpSocket2" + datagramPackage.getPort() + "=" + datagramPackage.getAddress() + "=" + bytesToHexString(m));
byte[] bytes = datagramPackage.getData();
LogUtils.e("UdpSocket3" + bytesToHexString(bytes));
String msg = bytesToHexString(m);
LogUtils.e(msg);
Message msg1 = handler.obtainMessage();
msg1.obj = bytesToHexString(bytes);
msg1.what = 10;
handler.sendMessage(msg1);
}
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
public void getUdpData() {
try {
DatagramPacket udpPacket = new DatagramPacket(data, data.length);
while (getMessage) {
try {
socket.receive(udpPacket);
} catch (Exception e) {
}
//接收到的byte[]
byte[] m = Arrays.copyOf(udpPacket.getData(), udpPacket.getLength());
}
socket.close();
} catch (Exception e1) {
e1.printStackTrace();
}
}
public void sendUdp(final String message, final String address, final int port) {
ExecutorUtil.execute(new Runnable() {
@Override
public void run() {
try {
InetAddress serverAddress = null;
serverAddress = InetAddress.getByName(address);
byte data[] = message.getBytes();
DatagramPacket datagramPacket = new DatagramPacket(data, data.length, serverAddress, port);
socket.send(datagramPacket);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public static String bytesToHexString(byte[] bytes) {
String result = "";
for (int i = 0; i < bytes.length; i++) {
String hexString = Integer.toHexString(bytes[i] & 0xFF);
if (hexString.length() == 1) {
hexString = '0' + hexString;
}
result += hexString.toUpperCase();
}
return result;
}
}
使用方法：
private UdpSocket udpSocket;
try { udpSocket = new UdpSocket(handler); udpSocket.sendUdp(message + "", ip, server_port); udpSocket.initSocket();} catch (Exception e) { e.printStackTrace();}
传入的message 是发送的消息数据。类型String.