Android如何接收udp
时间: 2023-04-05 10:02:55 浏览: 49
数据包?
Android可以通过DatagramSocket类来接收UDP数据包。首先创建一个DatagramSocket对象,然后创建一个DatagramPacket对象来存储接收到的数据。接着调用DatagramSocket的receive()方法来接收数据包,该方法会阻塞直到接收到数据包为止。最后从DatagramPacket对象中获取数据即可。
相关问题
android接收udp广播
要在 Android 应用程序中接收 UDP 广播,可以使用 DatagramSocket 类。以下是一个示例代码:
```java
public class UdpBroadcastReceiver extends Thread {
private MulticastSocket socket;
private boolean running;
private byte[] buf = new byte[256];
public void run() {
try {
socket = new MulticastSocket(4446);
InetAddress group = InetAddress.getByName("230.0.0.0");
socket.joinGroup(group);
running = true;
while (running) {
DatagramPacket packet = new DatagramPacket(buf, buf.length);
socket.receive(packet);
String received = new String(packet.getData(), 0, packet.getLength());
Log.d("UdpBroadcastReceiver", "Received: " + received);
}
socket.leaveGroup(group);
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
public void close() {
running = false;
}
}
```
此代码创建一个 MulticastSocket 对象并加入一个组。它在一个循环中接收广播,直到调用 close() 方法停止接收。接收到的消息将被打印到 Android 的日志中。
你可以在应用程序的任何地方使用此代码来启动接收器线程:
```java
UdpBroadcastReceiver receiver = new UdpBroadcastReceiver();
receiver.start();
```
记得在应用程序关闭时调用 close() 方法来停止接收线程。
帮我写一段Android接收udp的代码
好的,以下是一段Android接收UDP的代码:
```
public class UdpReceiver extends Thread {
private DatagramSocket socket;
private boolean running;
private byte[] buffer = new byte[1024];
public UdpReceiver() throws SocketException {
socket = new DatagramSocket(5000);
}
public void run() {
running = true;
while (running) {
DatagramPacket packet = new DatagramPacket(buffer, buffer.length);
try {
socket.receive(packet);
String message = new String(packet.getData(), 0, packet.getLength());
Log.d("UDP", "Received message: " + message);
} catch (IOException e) {
e.printStackTrace();
}
}
socket.close();
}
public void close() {
running = false;
}
}
```
这段代码创建了一个DatagramSocket对象,并在端口5000上监听UDP消息。当收到消息时,它会将消息转换为字符串并打印到日志中。如果你想停止接收消息,可以调用close()方法。