TileEntityItemHandler.java

package choonster.testmod3.tileentity;

import choonster.testmod3.TestMod3;
import choonster.testmod3.util.InventoryUtils;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.inventory.Container;
import net.minecraft.item.ItemStack;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.tileentity.TileEntity;
import net.minecraft.util.EnumFacing;
import net.minecraft.world.World;
import net.minecraftforge.common.capabilities.Capability;
import net.minecraftforge.common.util.INBTSerializable;
import net.minecraftforge.items.CapabilityItemHandler;
import net.minecraftforge.items.IItemHandler;

import javax.annotation.Nullable;
import java.util.List;

/**
 * A {@link TileEntity} with a single {@link IItemHandler} inventory.
 *
 * @param <INVENTORY> The inventory type
 */
public abstract class TileEntityItemHandler<INVENTORY extends IItemHandler & INBTSerializable<NBTTagCompound>> extends TileEntity {
	/**
	 * The inventory.
	 */
	protected final INVENTORY inventory = createInventory();

	/**
	 * Create and return the inventory.
	 *
	 * @return The inventory
	 */
	protected abstract INVENTORY createInventory();

	/**
	 * Open the GUI for the specified player.
	 *
	 * @param world  The world
	 * @param player The player
	 */
	public void openGUI(World world, EntityPlayer player) {
		if (!world.isRemote) {
			player.openGui(TestMod3.MODID, getGuiId(), world, pos.getX(), pos.getY(), pos.getZ());
		}
	}

	/**
	 * Create a {@link Container} of this inventory for the specified player.
	 *
	 * @param player The player
	 * @return The Container
	 */
	public abstract Container createContainer(EntityPlayer player);

	/**
	 * Get the GUI ID.
	 *
	 * @return The GUI ID
	 */
	protected abstract int getGuiId();

	/**
	 * Get the inventory contents to drop.
	 *
	 * @return The drops list
	 */
	public List<ItemStack> getDrops() {
		return InventoryUtils.dropItemHandlerContents(inventory, getWorld().rand);
	}

	@Override
	public void readFromNBT(NBTTagCompound compound) {
		super.readFromNBT(compound);
		inventory.deserializeNBT(compound.getCompoundTag("ItemHandler"));
	}

	@Override
	public NBTTagCompound writeToNBT(NBTTagCompound compound) {
		super.writeToNBT(compound);
		compound.setTag("ItemHandler", inventory.serializeNBT());
		return compound;
	}

	@Override
	public boolean hasCapability(Capability<?> capability, @Nullable EnumFacing facing) {
		return capability == CapabilityItemHandler.ITEM_HANDLER_CAPABILITY || super.hasCapability(capability, facing);
	}

	@Override
	public <T> T getCapability(Capability<T> capability, @Nullable EnumFacing facing) {
		if (capability == CapabilityItemHandler.ITEM_HANDLER_CAPABILITY) {
			return CapabilityItemHandler.ITEM_HANDLER_CAPABILITY.cast(inventory);
		}

		return super.getCapability(capability, facing);
	}
}