Check "is single player" and not run mod at all

[Roland]

Hello. I write anti-griefer server-side-only mod. It has connection to database. So I need to run in on multiplayer only, not in single player.

I spent some time trying to determine is it singleplayer or not and how to "stop" (not load? not run?) mod correctly, but still no ideas.

Now I have the following code, that I copy in every method of my mod. Looks ugly and not right.

Checking:

private boolean isSinglePlayer() {
    try {
        if (ServerLifecycleHooks.getCurrentServer().isSingleplayer())
            return true;
    } catch (Exception e) {
        return true;
    }
    return false;
}

Using:

@SubscribeEvent
public void serverLoad(RegisterCommandsEvent event) throws IOException {
    if (isSinglePlayer()) {
        return;
    }
    // ...
}

Just in case: ServerLifeCycleHooks is needed because I don't know any other GLOBAL class that can return me current server. try-catch is needed because "current server" may not even exist. And using my "serverLoad" method in every other methods... Ugh. I'm speechless.

Can you tell me, guys, how to do it correctly?

[warjort]

 

@Mod.EventBusSubscriber(modid = MODID, value = Dist.DEDICATED_SERVER)

Or for more details:

https://forge.gemwire.uk/wiki/Sides

Please familiarise yourself with the whole wiki.

[Roland]

1 hour ago, warjort said:

Or for more details:

I tried it:

@Mod(MyLogger.MOD_ID)
@Mod.EventBusSubscriber(modid = MyLogger.MOD_ID, value = Dist.DEDICATED_SERVER)
public class MyLogger {
    // ...

But:

1) It works only if I add "@OnlyIn(Dist.DEDICATED_SERVER)" above every event handler like this:

@SubscribeEvent
@OnlyIn(Dist.DEDICATED_SERVER)
public void onPlayerTick(TickEvent.PlayerTickEvent event) {
    // ...

2) My command event handler stop working. Handler:

@SubscribeEvent
@OnlyIn(Dist.DEDICATED_SERVER)
public void onPlayerEnteredCommand(CommandEvent event) {
    String playerName = Objects.requireNonNull(event.getParseResults().getContext().getSource().getPlayer()).getGameProfile().getName();
    if (playersCanExecListOfCommands.get(playerName) != true) {
        event.setCanceled(true);
    }
}

Error:

[Server thread/ERROR] [ne.mi.ev.EventBus/EVENTBUS]: Exception caught during firing event: null
        Index: 1
        Listeners:
                0: NORMAL
                1: ASM: ru.tester.mylogger.MyMod@59a50d8a onPlayerEnteredCommand(Lnet/minecraftforge/event/CommandEvent;)V
java.lang.NullPointerException
        at java.base/java.util.Objects.requireNonNull(Objects.java:208)
        at TRANSFORMER/[email protected]/ru.tester.mylogger.MyLogger.onPlayerEnteredCommand(PinMod.java:94)
        at TRANSFORMER/[email protected]/ru.tester.mylogger.__MyLogger_onPlayerEnteredCommand_CommandEvent.invoke(.dynamic)

 

[warjort]

@ModEventBusSubscriber only works with static methods.

https://forge.gemwire.uk/wiki/Events (the very next entry on the wiki after the one I posted above).

if you are using @OnlyIn you are doing it wrong.