Basic NBT Schematic load/pasting

Schematic.java

package com.desive.schematic;

import net.minecraft.server.v1_12_R1.NBTCompressedStreamTools;
import net.minecraft.server.v1_12_R1.NBTTagCompound;
import org.bukkit.Location;
import org.bukkit.World;
import org.bukkit.block.Block;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

/*
 Created by Jack DeSive on 2/23/2018 at 10:00 PM
*/
public class Schematic {

    private short[] blocks;
    private byte[] data;
    private short width;
    private short length;
    private short height;

    public Schematic(short[] blocks, byte[] data, short width, short length, short height) {
        this.blocks = blocks;
        this.data = data;
        this.width = width;
        this.length = length;
        this.height = height;
    }

    public short[] getBlocks() {
        return blocks;
    }

    public byte[] getData() {
        return data;
    }

    public short getWidth() {
        return width;
    }

    public short getLength() {
        return length;
    }

    public short getHeight() {
        return height;
    }

    public static void pasteSchematic(World world, Location loc, Schematic schematic) {
        short[] blocks = schematic.getBlocks();
        byte[] blockData = schematic.getData();

        short length = schematic.getLength();
        short width = schematic.getWidth();
        short height = schematic.getHeight();

        for (int x = 0; x < width; ++x) {
            for (int y = 0; y < height; ++y) {
                for (int z = 0; z < length; ++z) {
                    int index = y * width * length + z * width + x;
                    Block block = new Location(world, x + loc.getX(), y + loc.getY(), z + loc.getZ()).getBlock();
                    block.setTypeIdAndData(blocks[index], blockData[index], true);
                }
            }
        }
    }

    public static Schematic loadSchematic(File file) throws IOException {
        InputStream fis = new FileInputStream(file);
        NBTTagCompound nbtData = NBTCompressedStreamTools.a(fis);

        short width = nbtData.getShort("Width");
        short length = nbtData.getShort("Length");
        short height = nbtData.getShort("Height");

        byte[] blockId = nbtData.getByteArray("Blocks");
        byte[] blockData = nbtData.getByteArray("Data");
        byte[] addId = new byte[0];
        short[] blocks = new short[blockId.length];

        if (nbtData.hasKey("AddBlocks")) {
            addId = nbtData.getByteArray("AddBlocks");
        }

        for (int index = 0; index < blockId.length; index++) {
            if ((index >> 1) >= addId.length) {
                blocks[index] = (short) (blockId[index] & 0xFF);
            } else {
                if ((index & 1) == 0) {
                    blocks[index] = (short) (((addId[index >> 1] & 0x0F) << 8) + (blockId[index] & 0xFF));
                } else {
                    blocks[index] = (short) (((addId[index >> 1] & 0xF0) << 4) + (blockId[index] & 0xFF));
                }
            }
        }

        return new Schematic(blocks, blockData, width, length, height);
    }
}