Files
XPlaneConnectCSP/Java/ProjectModels/CognitiveModel/ModelFiles/XPCdependencies/XPlaneConnectDiscovery.java
2024-12-05 23:48:34 -05:00

95 lines
2.7 KiB
Java

package CognitiveModel.ModelFiles.XPCdependencies;
import CognitiveModel.ModelFiles.*;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.InetAddress;
import java.net.MulticastSocket;
import java.net.SocketException;
/**
* The XPlaneConnectDiscovery joins a UDP multi cast group and listens for BECN packets published by
* XPlaneConnect server plugin. It allows to clients to discover XPlane instances and be sure that the XPlanePlugin is
* installed.
*/
public class XPlaneConnectDiscovery implements AutoCloseable {
private static int DEFAULT_PORT = 49710;
private static String DEFAULT_ADDRESS = "239.255.1.1";
private BeaconReceivedListener mListener;
private MulticastSocket socket = null;
private byte[] buf = new byte[256];
private int mPort;
private String mAddress;
private BeaconParser parser = new BeaconParser();
private XPlaneConnectDiscovery(int port, String address) {
mPort = port;
mAddress = address;
}
public XPlaneConnectDiscovery() {
this(DEFAULT_PORT, DEFAULT_ADDRESS);
}
public void start(DiscoveryConnectionCallback callback) throws IOException {
onBeaconReceived(beacon -> {
this.close();
try {
XPlaneConnect xpc = new XPlaneConnect(beacon);
callback.onConnectionEstablished(xpc);
} catch (SocketException e) {
System.err.println("Could not connect to a discovered XplaneConnect " +beacon+ ": " + e.getMessage());
}
});
start();
}
@SuppressWarnings("deprecation") // Added custom
public void start() throws IOException {
System.out.println("Starting XPlane Connect discovery");
socket = new MulticastSocket(mPort);
InetAddress group = InetAddress.getByName(mAddress);
socket.joinGroup(group);
while (socket != null) {
DatagramPacket packet = new DatagramPacket(buf, buf.length);
socket.receive(packet);
if (mListener == null) {
continue;
}
try {
Beacon beacon = parser.readBCN(packet);
mListener.onBeaconReceived(beacon);
} catch (IOException ex) {
System.err.println("Received packet on discovery group but could not parse it: " + ex);
}
}
close();
System.out.println("XPlane Connect discovery ended");
}
public void onBeaconReceived(BeaconReceivedListener mListener) {
this.mListener = mListener;
}
@Override
public void close() {
if (socket != null) {
socket.close();
socket = null;
}
}
public void stop() {
close();
}
}