ItemStackSet.java

/* 
 * Copyright (c) CovertJaguar, 2014 http://railcraft.info
 * 
 * This code is the property of CovertJaguar
 * and may only be used with explicit written
 * permission unless otherwise specified on the
 * license page at http://railcraft.info/wiki/info:license.
 */
package mods.railcraft.common.util.inventory;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import net.minecraft.item.ItemStack;

/**
 * This is a custom data structure designed specifically for using ItemStacks as
 * elements of a Set.
 *
 * Its backed by an ArrayList, so as expected, most operations result in
 * traversing the list one or more times.
 *
 * @author CovertJaguar <http://www.railcraft.info>
 */
public class ItemStackSet implements Set<ItemStack> {

    private List<ItemStack> set = new ArrayList<ItemStack>();

    @Override
    public int size() {
        return set.size();
    }

    @Override
    public boolean isEmpty() {
        return set.isEmpty();
    }

    @Override
    public boolean contains(Object obj) {
        if (!(obj instanceof ItemStack)) {
            return false;
        }
        ItemStack check = (ItemStack) obj;
        for (ItemStack stack : set) {
            if (InvTools.isItemEqual(stack, check)) {
                return true;
            }
        }
        return false;
    }

    @Override
    public Iterator<ItemStack> iterator() {
        return set.iterator();
    }

    @Override
    public Object[] toArray() {
        return set.toArray();
    }

    @Override
    public <T> T[] toArray(T[] a) {
        return set.toArray(a);
    }

    @Override
    public boolean add(ItemStack e) {
        if (contains(e)) {
            return false;
        }
        set.add(e);
        return true;
    }

    @Override
    public boolean remove(Object obj) {
        if (!(obj instanceof ItemStack)) {
            return false;
        }
        boolean changed = false;
        ItemStack check = (ItemStack) obj;
        Iterator<ItemStack> it = set.iterator();
        while (it.hasNext()) {
            ItemStack stack = it.next();
            if (InvTools.isItemEqual(stack, check)) {
                it.remove();
                changed = true;
            }
        }
        return changed;
    }

    @Override
    public boolean containsAll(Collection<?> c) {
        for (Object obj : c) {
            if (!(obj instanceof ItemStack)) {
                return false;
            }
            if (!contains((ItemStack) obj)) {
                return false;
            }
        }
        return true;
    }

    @Override
    public boolean addAll(Collection<? extends ItemStack> c) {
        boolean changed = false;
        for (ItemStack stack : c) {
            changed |= add(stack);
        }
        return changed;
    }

    @Override
    public boolean retainAll(Collection<?> c) {
        boolean changed = false;
        Iterator<ItemStack> it = set.iterator();
        while (it.hasNext()) {
            ItemStack stack = it.next();
            if (!c.contains(it)) {
                it.remove();
                changed = true;
            }
        }
        return changed;
    }

    @Override
    public boolean removeAll(Collection<?> c) {
        boolean changed = false;
        Iterator<ItemStack> it = set.iterator();
        while (it.hasNext()) {
            ItemStack stack = it.next();
            if (c.contains(it)) {
                it.remove();
                changed = true;
            }
        }
        return changed;
    }

    @Override
    public void clear() {
        set.clear();
    }
}