Show geo locations from DMR on map (#1001)

Thank you!

src/main/java/io/github/dsheirer/util/PacketUtil.java

@@ -0,0 +1,49 @@
+package io.github.dsheirer.util;
+
+import io.github.dsheirer.module.decode.ip.IPacket;
+import io.github.dsheirer.module.decode.ip.ipv4.IPV4Packet;
+import io.github.dsheirer.module.decode.ip.lrrp.LRRPPacket;
+import io.github.dsheirer.module.decode.ip.lrrp.token.Position;
+import io.github.dsheirer.module.decode.ip.lrrp.token.Token;
+import io.github.dsheirer.module.decode.ip.udp.UDPPacket;
+import org.jdesktop.swingx.mapviewer.GeoPosition;
+
+public class PacketUtil {
+    public static GeoPosition extractGeoPosition(IPacket packet) {
+        if (packet instanceof IPV4Packet) {
+            IPV4Packet ipPacket = (IPV4Packet) packet;
+
+            if (ipPacket.getPayload() instanceof UDPPacket) {
+                UDPPacket udpPacket = (UDPPacket) ipPacket.getPayload();
+                return extractGeoPosition(udpPacket);
+            }
+
+            return null;
+        }
+
+        if (packet instanceof UDPPacket) {
+            UDPPacket udpPacket = (UDPPacket) packet;
+
+            if (udpPacket.getPayload() instanceof LRRPPacket) {
+                LRRPPacket lrrpPacket = (LRRPPacket) udpPacket.getPayload();
+                return extractGeoPosition(lrrpPacket);
+            }
+
+            return null;
+        }
+
+        if (packet instanceof LRRPPacket) {
+            LRRPPacket lrrpPacket = (LRRPPacket) packet;
+
+            for (Token token: lrrpPacket.getTokens())
+            {
+                if (token instanceof Position) {
+                    Position position = (Position) token;
+                    return new GeoPosition(position.getLatitude(), position.getLongitude());
+                }
+            }
+        }
+
+        return null;
+    }
+}