NMS Custom Entity

目的

透過繼承 NMS Mob 類別並覆寫 registerGoals() 加入自訂 PathfinderGoal，實現自定義 AI 行為。適用於客製化 Boss、NPC、守衛等場景。

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平台需求

• Paper 1.21 – 1.21.3
• Paperweight userdev 1.7.2+
• paper-plugin.yml（確保 NMS 早於 Bukkit plugin 載入）

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產生的代碼

CustomZombie.java

@SuppressWarnings("UnstableApiUsage")
public class CustomZombie extends Zombie {

    @Override
    protected void registerGoals() {
        this.goalSelector.addGoal(0, new FloatGoal(this));
        this.goalSelector.addGoal(1, new FollowClosestPlayerGoal(this, 1.2D, 32.0D));
        this.goalSelector.addGoal(2, new MeleeAttackGoal(this, 1.0D, false));
        this.targetSelector.addGoal(1,
            new NearestAttackableTargetGoal<>(this, Player.class, true));
    }

    public static AttributeSupplier.Builder createAttributes() {
        return Zombie.createAttributes()
            .add(Attributes.MAX_HEALTH, 40.0D)
            .add(Attributes.ATTACK_DAMAGE, 8.0D);
    }
}

FollowClosestPlayerGoal.java（自訂 PathfinderGoal）

public class FollowClosestPlayerGoal extends Goal {
    @Override public boolean canUse() { /* 找最近玩家 */ }
    @Override public void start() { mob.getNavigation().moveTo(target, speed); }
    @Override public void tick() { /* 每 10 tick 重新規劃路徑 */ }
}

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執行緒安全

• 實體建立、addFreshEntity() 必須在主執行緒
• PathfinderGoal.tick() 由 NMS tick 迴圈在主執行緒呼叫