Code/net/minecraft/world/entity/monster/Monster.java

package net.minecraft.world.entity.monster;

import java.util.function.Predicate;
import net.minecraft.core.BlockPos;
import net.minecraft.server.level.ServerLevel;
import net.minecraft.sounds.SoundEvent;
import net.minecraft.sounds.SoundEvents;
import net.minecraft.sounds.SoundSource;
import net.minecraft.util.RandomSource;
import net.minecraft.world.Difficulty;
import net.minecraft.world.damagesource.DamageSource;
import net.minecraft.world.entity.EntitySpawnReason;
import net.minecraft.world.entity.EntityType;
import net.minecraft.world.entity.LivingEntity;
import net.minecraft.world.entity.Mob;
import net.minecraft.world.entity.PathfinderMob;
import net.minecraft.world.entity.ai.attributes.AttributeSupplier;
import net.minecraft.world.entity.ai.attributes.Attributes;
import net.minecraft.world.entity.player.Player;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.item.Items;
import net.minecraft.world.item.ProjectileWeaponItem;
import net.minecraft.world.level.Level;
import net.minecraft.world.level.LevelAccessor;
import net.minecraft.world.level.LevelReader;
import net.minecraft.world.level.LightLayer;
import net.minecraft.world.level.ServerLevelAccessor;
import net.minecraft.world.level.dimension.DimensionType;

public abstract class Monster extends PathfinderMob implements Enemy {
    protected Monster(EntityType<? extends Monster> p_33002_, Level p_33003_) {
        super(p_33002_, p_33003_);
        this.xpReward = 5;
    }

    @Override
    public SoundSource getSoundSource() {
        return SoundSource.HOSTILE;
    }

    @Override
    public void aiStep() {
        this.updateSwingTime();
        this.updateNoActionTime();
        super.aiStep();
    }

    protected void updateNoActionTime() {
        float f = this.getLightLevelDependentMagicValue();
        if (f > 0.5F) {
            this.noActionTime += 2;
        }
    }

    @Override
    protected boolean shouldDespawnInPeaceful() {
        return true;
    }

    @Override
    protected SoundEvent getSwimSound() {
        return SoundEvents.HOSTILE_SWIM;
    }

    @Override
    protected SoundEvent getSwimSplashSound() {
        return SoundEvents.HOSTILE_SPLASH;
    }

    @Override
    protected SoundEvent getHurtSound(DamageSource p_33034_) {
        return SoundEvents.HOSTILE_HURT;
    }

    @Override
    protected SoundEvent getDeathSound() {
        return SoundEvents.HOSTILE_DEATH;
    }

    @Override
    public LivingEntity.Fallsounds getFallSounds() {
        return new LivingEntity.Fallsounds(SoundEvents.HOSTILE_SMALL_FALL, SoundEvents.HOSTILE_BIG_FALL);
    }

    @Override
    public float getWalkTargetValue(BlockPos p_33013_, LevelReader p_33014_) {
        return -p_33014_.getPathfindingCostFromLightLevels(p_33013_);
    }

    public static boolean isDarkEnoughToSpawn(ServerLevelAccessor p_219010_, BlockPos p_219011_, RandomSource p_219012_) {
        if (p_219010_.getBrightness(LightLayer.SKY, p_219011_) > p_219012_.nextInt(32)) {
            return false;
        } else {
            DimensionType dimensiontype = p_219010_.dimensionType();
            int i = dimensiontype.monsterSpawnBlockLightLimit();
            if (i < 15 && p_219010_.getBrightness(LightLayer.BLOCK, p_219011_) > i) {
                return false;
            } else {
                int j = p_219010_.getLevel().isThundering() ? p_219010_.getMaxLocalRawBrightness(p_219011_, 10) : p_219010_.getMaxLocalRawBrightness(p_219011_);
                return j <= dimensiontype.monsterSpawnLightTest().sample(p_219012_);
            }
        }
    }

    public static boolean checkMonsterSpawnRules(
        EntityType<? extends Monster> p_219014_, ServerLevelAccessor p_219015_, EntitySpawnReason p_361279_, BlockPos p_219017_, RandomSource p_219018_
    ) {
        return p_219015_.getDifficulty() != Difficulty.PEACEFUL
            && (EntitySpawnReason.ignoresLightRequirements(p_361279_) || isDarkEnoughToSpawn(p_219015_, p_219017_, p_219018_))
            && checkMobSpawnRules(p_219014_, p_219015_, p_361279_, p_219017_, p_219018_);
    }

    public static boolean checkAnyLightMonsterSpawnRules(
        EntityType<? extends Monster> p_219020_, LevelAccessor p_219021_, EntitySpawnReason p_362154_, BlockPos p_219023_, RandomSource p_219024_
    ) {
        return p_219021_.getDifficulty() != Difficulty.PEACEFUL && checkMobSpawnRules(p_219020_, p_219021_, p_362154_, p_219023_, p_219024_);
    }

    public static AttributeSupplier.Builder createMonsterAttributes() {
        return Mob.createMobAttributes().add(Attributes.ATTACK_DAMAGE);
    }

    @Override
    public boolean shouldDropExperience() {
        return true;
    }

    @Override
    protected boolean shouldDropLoot() {
        return true;
    }

    public boolean isPreventingPlayerRest(ServerLevel p_369968_, Player p_33036_) {
        return true;
    }

    @Override
    public ItemStack getProjectile(ItemStack p_33038_) {
        if (p_33038_.getItem() instanceof ProjectileWeaponItem) {
            Predicate<ItemStack> predicate = ((ProjectileWeaponItem)p_33038_.getItem()).getSupportedHeldProjectiles();
            ItemStack itemstack = ProjectileWeaponItem.getHeldProjectile(this, predicate);
            return itemstack.isEmpty() ? new ItemStack(Items.ARROW) : itemstack;
        } else {
            return ItemStack.EMPTY;
        }
    }
}