Register a Custom Flag

Register an environment flag

public final class WeatherAddon extends JavaPlugin implements Listener {
    private static final EnvFlag NO_RAIN = new EnvFlag(
            "weather_addon_no_rain",
            "No Rain",
            "Whether rain is blocked in this dominion.",
            false,
            true,
            Material.SUNFLOWER
    );

    @Override
    public void onEnable() {
        if (!Flags.registerEnvFlag(this, NO_RAIN)) {
            getLogger().warning("Dominion rejected the custom flag.");
            return;
        }

        EnvFlagGroup weather = new EnvFlagGroup(
                "weather-addon",
                "Weather Addon",
                "Weather rules provided by this addon.",
                Material.SUNFLOWER
        );
        weather.addFlag(NO_RAIN);
        FlagGroups.registerEnvFlagGroup(this, weather);

        Flags.applyChanges().thenRun(() ->
                getLogger().info("NO_RAIN is ready."));

        getServer().getPluginManager().registerEvents(this, this);
    }
}

Implement flag behavior

Registering a flag only adds it to Dominion’s flag data, configuration, and UI systems. The addon still needs to read it in its own event listener and implement the behavior:

@EventHandler
public void onWeatherChange(WeatherChangeEvent event) {
    if (!event.toWeather()) return;

    for (Player player : event.getWorld().getPlayers()) {
        DominionDTO dominion = DominionAPI.getInstance()
                .getDominion(player.getLocation());
        if (dominion == null) continue;

        if (dominion.getEnvFlagValue(NO_RAIN)) {
            event.setCancelled(true);
            return;
        }
    }
}

This example only demonstrates how to read the data. Weather is a world-level event; a real project must define the priority when multiple claims are present instead of treating the first player’s result as the conclusion for the entire world.

Use a permission flag

The implementation of PriFlag is similar, but the check needs a player and a location:

if (!DominionAPI.getInstance().checkPrivilegeFlagSilence(
        location,
        USE_SPECIAL_TOOL,
        player
)) {
    return;
}

The addon must listen for and cancel the relevant Bukkit event for the actual action of a custom permission flag. Do not use only the MemberDTO flag Map as a substitute for the final permission check.