kryonet server crashing when receiving an object

Question

I have a problem with Kryonet server crashing after receiving an object from client. Server code:

package com.qookie.miner_server;
import java.io.IOException;
import com.esotericsoftware.kryo.Kryo;
import com.esotericsoftware.kryonet.Server;
import com.esotericsoftware.minlog.Log;
import com.qookie.miner_server.Packet.*;


public class MinerServer_Main {
    private Server server;

    public MinerServer_Main() throws IOException {
        this.server = new Server();
        RegisterPackets();
        server.addListener(new NetworkListener());
        server.bind(8888,8888);
        server.start();
    }

    private void RegisterPackets() {
        Kryo kryo = server.getKryo();
        kryo.register(Packet0LoginRequest.class);
        kryo.register(Packet1LoginAnswer.class);
        kryo.register(Packet2Message.class);

    }
    public static void main(String[] args) {
        try {
            new MinerServer_Main();

        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

And here is a server listener:

package com.qookie.miner_server;
import com.esotericsoftware.kryonet.Connection;
import com.esotericsoftware.kryonet.Listener;
import com.qookie.miner_server.Packet.*;

public class NetworkListener extends Listener {
    public void connected(Connection arg0) {
        System.out.println("[SERVER] Someone has connected");
    }

    public void disconnected(Connection arg0) {
        System.out.println("[SERVER] Someone has disconnected");
    }

    public void received(Connection c, Object o) {
        if (o instanceof Packet0LoginRequest) {
            Packet1LoginAnswer p = new Packet().new Packet1LoginAnswer();
            p.accepted = true;
            c.sendTCP(p);
        }

        if (o instanceof Packet2Message) {
            String message = ((Packet2Message) o).msg;
            System.out.println("[CLIENT] " + message);
        }
    }
}

And here is Packet.java file:

package com.qookie.miner_server;

public class Packet {
    public class Packet0LoginRequest {
        public Packet0LoginRequest() {}
        public void init() {

        }
    };

    public class Packet1LoginAnswer {
        public boolean accepted;
        public Packet1LoginAnswer() {}
        public void init() {

        }
    };

    public class Packet2Message {
        public Packet2Message() {}
        public String msg;
        public void init() {

        }
    };

    public Packet() {

    }

}

When user connects client sends a Packet0LoginRequest and server sends back Packet1LoginAnswer. When boolean variable in Packet1LoginAnswer is true, client starts reading from scanner and sending new Packet2Message. But the server crashes when receiving Packet0LoginRequest.

Here is the crash log: Server crash log

score 1 · Accepted Answer · answered May 24 '16 at 06:34

It think kryonet fails to load your constructor.

Following approach worked from me:

public class Network {

    static public final int tcpPort = 54555;
    static public final int udpPort = 54777;

    // This registers objects that are going to be sent over the network.
    static public void register (EndPoint endPoint) {
        Kryo kryo = endPoint.getKryo();
        kryo.register(ServerResponse.class);
        kryo.register(ClientRequest.class); 

    }

    static public class ServerResponse {
    ...
       public ServerResponse(){
               super();
       }
...
    }

    static public class ClientRequest {
    ...
        public ClientRequest(){
               super();
        }
    ...
   }
...
}

kryonet server crashing when receiving an object

1 Answers1