Whenever I installed my very first 1.17 mod.

The spawning of the entity as well as it's spawn egg didn't show up.

Here's the code to explain why:

package com.gohkenytp.coyote.common.items;


import java.util.*;

import net.minecraft.world.level.block.DispenserBlock;
import net.minecraft.core.dispenser.DefaultDispenseItemBehavior;
import net.minecraft.core.BlockSource;
import net.minecraft.world.entity.MobSpawnType;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.core.Direction;
import net.minecraftforge.common.util.Lazy;
import net.minecraftforge.common.util.NonNullSupplier;

import net.minecraft.world.entity.EntityType;

import net.minecraft.world.item.Item;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.item.SpawnEggItem;
import net.minecraftforge.fml.util.ObfuscationReflectionHelper;
import net.minecraftforge.fmllegacy.RegistryObject;

public class CoyoteEgg extends SpawnEggItem {

    protected static final List<CoyoteEgg> UNADDED_EGGS = new ArrayList<CoyoteEgg>();
    private final Lazy<? extends EntityType<?>> entityTypeSupplier;

    public CoyoteEgg(final NonNullSupplier<? extends EntityType<?>> entityTypeSupplier, final int primaryColour,
                      final int secondaryColour, final Item.Properties properties) {
        super(null, primaryColour, secondaryColour, properties);
        this.entityTypeSupplier = Lazy.of(entityTypeSupplier::get);
        UNADDED_EGGS.add(this);
    }

    public CoyoteEgg(final RegistryObject<? extends EntityType<?>> entityTypeSupplier, final int primaryColour,
                      final int secondaryColour, final Item.Properties properties) {
        super(null, primaryColour, secondaryColour, properties);
        this.entityTypeSupplier = Lazy.of(entityTypeSupplier::get);
        UNADDED_EGGS.add(this);
    }

    public static void regSpawnEggs() {
        final Map<EntityType<?>, SpawnEggItem> EGGS = ObfuscationReflectionHelper.getPrivateValue(SpawnEggItem.class,
                null, "field_195987_b");
        DefaultDispenseItemBehavior dispenseBehaviour = new DefaultDispenseItemBehavior() {
            @Override
            protected ItemStack execute(BlockSource source, ItemStack stack) {
                Direction direction = source.getBlockState().getValue(DispenserBlock.FACING);
                EntityType<?> type = ((SpawnEggItem) stack.getItem()).getType(stack.getTag());
                type.spawn(source.getLevel(), stack, null, source.getPos().relative(direction),
                        MobSpawnType.DISPENSER, direction != Direction.UP, false);
                stack.shrink(1);
                return stack;
            }
        };

        for (final SpawnEggItem spawnEgg : UNADDED_EGGS) {
            EGGS.put(spawnEgg.getType(null), spawnEgg);
            DispenserBlock.registerBehavior(spawnEgg, dispenseBehaviour);
        }
        UNADDED_EGGS.clear();
    }

    @Override
    public EntityType<?> getType(CompoundTag nbt) {
        return this.entityTypeSupplier.get();
    }

}

 

Tried it but it didn't work.

show what you tried 

I got the SpawnEgg set already and I figured it out. Until I came across this:

Type parameter 'com.gohkenytp.coyote.common.entities.CoyoteEntity' is not within its bound; should extend 'net.minecraft.world.entity.animal.Wolf'

I need help with this immediately!