LifeSpan

package net.pl3x.bukkit.lifespan;

import org.bukkit.Bukkit;
import org.bukkit.entity.Entity;
import org.bukkit.entity.LivingEntity;
import org.bukkit.event.EventHandler;
import org.bukkit.event.EventPriority;
import org.bukkit.event.Listener;
import org.bukkit.event.entity.CreatureSpawnEvent;
import org.bukkit.event.entity.EntityDamageEvent;
import org.bukkit.event.entity.EntityInteractEvent;
import org.bukkit.plugin.java.JavaPlugin;
import org.bukkit.scheduler.BukkitRunnable;

import java.util.HashMap;
import java.util.Map;
import java.util.UUID;

public class LifeSpan extends JavaPlugin implements Listener {
    private final Map<UUID, EntityTimer> timers = new HashMap<>();

    @Override
    public void onEnable() {
        getServer().getPluginManager().registerEvents(this, this);
    }

    @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
    public void onEntitySpawn(CreatureSpawnEvent event) {
        switch (event.getEntityType()) {
            case WITHER_SKELETON:
            case STRAY:
            case HUSK:
            case ZOMBIE_VILLAGER:
            case VEX:
            case CREEPER:
            case SKELETON:
            case SPIDER:
            case ZOMBIE:
            case SLIME:
            case GHAST:
            case PIG_ZOMBIE:
            case ENDERMAN:
            case CAVE_SPIDER:
            case SILVERFISH:
            case BLAZE:
            case MAGMA_CUBE:
            case WITCH:
            case ENDERMITE:
            case GUARDIAN:
                createTimer(event.getEntity());
        }
    }

    @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
    public void onEntityInteract(EntityInteractEvent event) {
        if (event.getEntity() instanceof LivingEntity) {
            handleInteract((LivingEntity) event.getEntity());
        }
    }

    @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
    public void onEntityDamage(EntityDamageEvent event) {
        if (event.getEntity() instanceof LivingEntity) {
            handleInteract((LivingEntity) event.getEntity());
        }
    }

    private void handleInteract(LivingEntity entity) {
        EntityTimer timer = timers.remove(entity.getUniqueId());
        if (timer == null) {
            return;
        }
        timer.cancel();
        createTimer(entity);
    }

    public void createTimer(LivingEntity entity) {
        EntityTimer timer = new EntityTimer(entity);
        timer.runTaskLater(this, 12000); // 10 minutes
        timers.put(entity.getUniqueId(), timer);
    }

    public class EntityTimer extends BukkitRunnable {
        private final UUID entity;

        public EntityTimer(LivingEntity entity) {
            this.entity = entity.getUniqueId();
        }

        @Override
        public void run() {
            Entity entity = Bukkit.getEntity(this.entity);
            if (entity == null) {
                cancel();
                return;
            }

            if (entity.isDead()) {
                cancel();
                return;
            }

            if (entity.getCustomName() != null) {
                cancel();
                return;
            }

            entity.remove();
        }

        @Override
        public void cancel() {
            timers.remove(entity);
        }
    }
}