Java Item.AIR属性代码示例

public void registerShapedRecipe(ShapedRecipe recipe) {
    Item result = recipe.getResult();
    this.recipes.put(recipe.getId(), recipe);
    Map<Integer, Map<Integer, Item>> ingredients = recipe.getIngredientMap();
    String hash = "";
    for (Map<Integer, Item> v : ingredients.values()) {
        for (Item item : v.values()) {
            if (item != null && item.getId() != Item.AIR) {
                hash += item.getId() + ":" + (!item.hasMeta() ? "?" : item.getDamage()) + "x" + item.getCount() + ",";
            }
        }

        hash += ";";
    }

    String index = result.getId() + ":" + (result.hasMeta() ? result.getDamage() : "");
    if (!this.recipeLookup.containsKey(index)) {
        this.recipeLookup.put(index, new HashMap<>());
    }

    this.recipeLookup.get(index).put(hash, recipe);
}
 

@Override
public CompoundTag getSpawnCompound() {
    if (!this.namedTag.contains("Item")) {
        this.setItem(new ItemBlock(new BlockAir()), false);
    }
    CompoundTag NBTItem = namedTag.getCompound("Item").copy();
    NBTItem.setName("Item");
    boolean item = NBTItem.getShort("id") == Item.AIR;
    return new CompoundTag()
            .putString("id", BlockEntity.ITEM_FRAME)
            .putInt("x", (int) this.x)
            .putInt("y", (int) this.y)
            .putInt("z", (int) this.z)
            .putCompound("Item", item ? NBTIO.putItemHelper(new ItemBlock(new BlockAir())) : NBTItem)
            .putByte("ItemRotation", item ? 0 : this.getItemRotation());
            // TODO: This crashes the client, why?
            // .putFloat("ItemDropChance", this.getItemDropChance());
}
 

@Override
public int onUpdate(int type) {
    int[] faces = {
            3,
            2,
            5,
            4,
    };
    if (type == Level.BLOCK_UPDATE_NORMAL) {
        if (this.meta >= 2 && this.meta <= 5) {
            if (this.getSide(BlockFace.fromIndex(faces[this.meta - 2])).getId() == Item.AIR) {
                this.getLevel().useBreakOn(this);
            }
            return Level.BLOCK_UPDATE_NORMAL;
        }
    }
    return 0;
}
 

@Override
public void setItem(int index, Item item) {
    int i = this.getSlotIndex(index);

    CompoundTag d = NBTIO.putItemHelper(item, index);

    if (item.getId() == Item.AIR || item.getCount() <= 0) {
        if (i >= 0) {
            this.namedTag.getList("Items").getAll().remove(i);
        }
    } else if (i < 0) {
        (this.namedTag.getList("Items", CompoundTag.class)).add(d);
    } else {
        (this.namedTag.getList("Items", CompoundTag.class)).add(i, d);
    }
}
 

@Override
public boolean canAddItem(Item item) {
    item = item.clone();
    boolean checkDamage = item.hasMeta();
    boolean checkTag = item.getCompoundTag() != null;
    for (int i = 0; i < this.getSize(); ++i) {
        Item slot = this.getItem(i);
        if (item.equals(slot, checkDamage, checkTag)) {
            int diff;
            if ((diff = slot.getMaxStackSize() - slot.getCount()) > 0) {
                item.setCount(item.getCount() - diff);
            }
        } else if (slot.getId() == Item.AIR) {
            item.setCount(item.getCount() - this.getMaxStackSize());
        }

        if (item.getCount() <= 0) {
            return true;
        }
    }

    return false;
}
 

@Override
public void setItem(int index, Item item) {
    int i = this.getSlotIndex(index);
    
    CompoundTag d = NBTIO.putItemHelper(item, index);

    // If item is air or count less than 0, remove the item from the "Items" list
    if (item.getId() == Item.AIR || item.getCount() <= 0) {
        if (i >= 0) {
            this.namedTag.getList("Items").remove(i);
        }
    } else if (i < 0) {
        // If it is less than i, then it is a new item, so we are going to add it at the end of the list
        (this.namedTag.getList("Items", CompoundTag.class)).add(d);
    } else {
        // If it is more than i, then it is an update on a slot, so we are going to overwrite the item in the list
        (this.namedTag.getList("Items", CompoundTag.class)).add(i, d);
    }
}
 

@Override
public int onUpdate(int type) {
    if (type == Level.BLOCK_UPDATE_NORMAL) {
        if (this.down().getId() == Item.AIR) {
            this.getLevel().useBreakOn(this);

            return Level.BLOCK_UPDATE_NORMAL;
        }
    }

    return 0;
}
 

@Override
public boolean clear(int index, boolean send) {
    if (this.slots.containsKey(index)) {
        Item item = new ItemBlock(new BlockAir(), null, 0);
        Item old = this.slots.get(index);
        InventoryHolder holder = this.getHolder();
        if (holder instanceof Entity) {
            EntityInventoryChangeEvent ev = new EntityInventoryChangeEvent((Entity) holder, this, old, item, index);
            Server.getInstance().getPluginManager().callEvent(ev);
            if (ev.isCancelled()) {
                this.sendSlot(index, this.getViewers());
                return false;
            }
            item = ev.getNewItem();
        }

        if (item.getId() != Item.AIR) {
            this.slots.put(index, item.clone());
        } else {
            this.slots.remove(index);
        }

        this.onSlotChange(index, old, send);
    }

    return true;
}
 

@Override
public boolean clear(int index) {
    if (this.slots.containsKey(index)) {
        Item item = new ItemBlock(new BlockAir(), null, 0);
        Item old = this.slots.get(index);
        InventoryHolder holder = this.getHolder();
        if (holder instanceof Entity) {
            EntityInventoryChangeEvent ev = new EntityInventoryChangeEvent((Entity) holder, old, item, index);
            Server.getInstance().getPluginManager().callEvent(ev);
            if (ev.isCancelled()) {
                this.sendSlot(index, this.getViewers());
                return false;
            }
            item = ev.getNewItem();
        }

        if (item.getId() != Item.AIR) {
            this.slots.put(index, item.clone());
        } else {
            this.slots.remove(index);
        }

        this.onSlotChange(index, old);
    }

    return true;
}
 

@Override
public int firstEmpty(Item item) {
    for (int i = 0; i < this.size; ++i) {
        if (this.getItem(i).getId() == Item.AIR) {
            return i;
        }
    }

    return -1;
}
 

@Override
public boolean place(Item item, Block block, Block target, BlockFace face, double fx, double fy, double fz, Player player) {
    Block down = this.down();
    if (down.getId() != Item.AIR) {
        this.getLevel().setBlock(block, this, true, true);
        return true;
    }
    return false;
}
 

@Override
public boolean onActivate(Item item, Player player) {
    BlockEntity blockEntity = this.getLevel().getBlockEntity(this);
    BlockEntityItemFrame itemFrame = (BlockEntityItemFrame) blockEntity;
    if (itemFrame.getItem().getId() == Item.AIR) {
        // We can't use Item.get(item.getId(), item.getDamage(), 1) because
        // we need to keep the item's NBT tags
        Item itemOnFrame = item.clone(); // So we clone the item
        itemOnFrame.setCount(1); // Change it to only one item (if we keep +1, visual glitches will happen)
        itemFrame.setItem(itemOnFrame); // And then we set it on the item frame
        // The item will be removed from the player's hand a few lines ahead
        this.getLevel().addSound(new ItemFrameItemAddedSound(this));
        if (player != null && player.isSurvival()) {
            int count = item.getCount();
            if (count-- <= 0) {
                player.getInventory().setItemInHand(new ItemBlock(new BlockAir(), 0, 0));
                return true;
            }
            item.setCount(count);
            player.getInventory().setItemInHand(item);
        }
    } else {
        int itemRot = itemFrame.getItemRotation();
        if (itemRot >= 7) {
            itemRot = 0;
        } else {
            itemRot++;
        }
        itemFrame.setItemRotation(itemRot);
        this.getLevel().addSound(new ItemFrameItemRotated(this));
    }
    return true;
}