src/de/steamwar/network/packets/NetworkHandler.java

@@ -23,6 +23,6 @@ import de.steamwar.network.packets.common.FightInfoPacket;
 import de.steamwar.network.packets.common.FightEndsPacket;
 
 public abstract class NetworkHandler {
-    public void handle(FightEndsPacket packet) {};
-    public void handle(FightInfoPacket packet) {};
+    public void handle(FightEndsPacket packet) {}
+    public void handle(FightInfoPacket packet) {}
 }

src/de/steamwar/network/packets/client/ClientNetworkHandler.java

@@ -23,8 +23,8 @@ import de.steamwar.network.packets.NetworkHandler;
 import de.steamwar.network.packets.server.*;
 
 public abstract class ClientNetworkHandler extends NetworkHandler {
-    public void handle(BaumemberUpdatePacket packet) {};
-    public void handle(CloseInventoryPacket packet) {};
+    public void handle(BaumemberUpdatePacket packet) {}
+    public void handle(CloseInventoryPacket packet) {}
     public void handle(InventoryPacket packet) {}
     public void handle(PingPacket packet) {}
     public void handle(StartingServerPacket packet) {}

src/de/steamwar/network/packets/client/InventoryCallbackPacket.java

@@ -29,12 +29,13 @@ import lombok.NonNull;
 public class InventoryCallbackPacket extends ClientPacket {
     private static final long serialVersionUID = -261823209186008718L;
     @NonNull
-    private int position;
+    private int position = -1;
     @NonNull
     private int owner;
     @NonNull
     private CallbackType type;
-    private ClickType clickType;
+    @NonNull
+    private ClickType clickType = ClickType.UNKNOWN;
 
     @Override
     public void handle(ServerNetworkHandler handler) {

src/de/steamwar/network/packets/server/ServerNetworkHandler.java

@@ -23,7 +23,7 @@ import de.steamwar.network.packets.NetworkHandler;
 import de.steamwar.network.packets.client.*;
 
 public abstract class ServerNetworkHandler extends NetworkHandler {
-    public void handle(ExecuteCommandPacket packet) {};
+    public void handle(ExecuteCommandPacket packet) {}
     public void handle(ImALobbyPacket packet) {}
     public void handle(InventoryCallbackPacket packet) {}
     public void handle(PrepareSchemPacket packet) {}