Java tutorial
/* * This file is part of Applied Energistics 2. * Copyright (c) 2013 - 2015, AlgorithmX2, All rights reserved. * * Applied Energistics 2 is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * Applied Energistics 2 is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with Applied Energistics 2. If not, see <http://www.gnu.org/licenses/lgpl>. */ package appeng.core.features; import javax.annotation.Nonnull; import com.google.common.base.Function; import com.google.common.base.Optional; import com.google.common.base.Preconditions; import net.minecraft.item.Item; import net.minecraft.item.ItemStack; import net.minecraft.world.IBlockAccess; import appeng.api.definitions.IItemDefinition; public final class DamagedItemDefinition implements IItemDefinition { private static final ItemTransformer ITEM_TRANSFORMER = new ItemTransformer(); private final Optional<IStackSrc> source; public DamagedItemDefinition(@Nonnull final IStackSrc source) { Preconditions.checkNotNull(source); if (source.isEnabled()) { this.source = Optional.of(source); } else { this.source = Optional.absent(); } } @Override public Optional<Item> maybeItem() { return this.source.transform(ITEM_TRANSFORMER); } @Override public Optional<ItemStack> maybeStack(final int stackSize) { return this.source.transform(new ItemStackTransformer(stackSize)); } @Override public boolean isEnabled() { return this.source.isPresent(); } @Override public boolean isSameAs(final ItemStack comparableStack) { if (comparableStack == null) { return false; } return this.isEnabled() && comparableStack.getItem() == this.source.get().getItem() && comparableStack.getItemDamage() == this.source.get().getDamage(); } @Override public boolean isSameAs(final IBlockAccess world, final int x, final int y, final int z) { return false; } private static class ItemTransformer implements Function<IStackSrc, Item> { @Override public Item apply(final IStackSrc input) { return input.getItem(); } } private static class ItemStackTransformer implements Function<IStackSrc, ItemStack> { private final int stackSize; public ItemStackTransformer(final int stackSize) { Preconditions.checkArgument(stackSize > 0); this.stackSize = stackSize; } @Override public ItemStack apply(final IStackSrc input) { return input.stack(this.stackSize); } } }