Simple NBTTagCompound Wrapper

NBTTag.java

package braayy.lib.util;

import org.bukkit.inventory.ItemStack;

import java.lang.reflect.Method;

@SuppressWarnings("ConstantConditions")
public class NBTTag {

    private static Class<?> NBT_TAG_COMPOUND_CLASS;

    private static Method HAS_KEY_METHOD;

    private static Method SET_STRING_METHOD;
    private static Method GET_STRING_METHOD;

    private static Method SET_INT_METHOD;
    private static Method GET_INT_METHOD;

    private static Method SET_METHOD;
    private static Method GET_COMPOUND_METHOD;

    private static Method AS_NMS_COPY_METHOD;
    private static Method AS_BUKKIT_MIRROR_METHOD;

    private static Method GET_TAG_METHOD;
    private static Method SET_TAG_METHOD;

    static {
        try {
            NBT_TAG_COMPOUND_CLASS = NMSUtil.getNMSClass("NBTTagCompound");

            HAS_KEY_METHOD = NBT_TAG_COMPOUND_CLASS.getDeclaredMethod("hasKey", String.class);

            SET_STRING_METHOD = NBT_TAG_COMPOUND_CLASS.getDeclaredMethod("setString", String.class, String.class);
            GET_STRING_METHOD = NBT_TAG_COMPOUND_CLASS.getDeclaredMethod("getString", String.class);

            SET_INT_METHOD = NBT_TAG_COMPOUND_CLASS.getDeclaredMethod("setInt", String.class, int.class);
            GET_INT_METHOD = NBT_TAG_COMPOUND_CLASS.getDeclaredMethod("getInt", String.class);

            Class<?> nbtBaseClass = NMSUtil.getNMSClass("NBTBase");

            SET_METHOD = NBT_TAG_COMPOUND_CLASS.getDeclaredMethod("set", String.class, nbtBaseClass);
            GET_COMPOUND_METHOD = NBT_TAG_COMPOUND_CLASS.getDeclaredMethod("getCompound", String.class);

            Class<?> craftItemStackClass = NMSUtil.getOBCClass("inventory.CraftItemStack");

            AS_NMS_COPY_METHOD = craftItemStackClass.getDeclaredMethod("asNMSCopy", ItemStack.class);

            Class<?> itemStackClass = NMSUtil.getNMSClass("ItemStack");

            AS_BUKKIT_MIRROR_METHOD = craftItemStackClass.getDeclaredMethod("asCraftMirror", itemStackClass);

            GET_TAG_METHOD = itemStackClass.getDeclaredMethod("getTag");
            SET_TAG_METHOD = itemStackClass.getDeclaredMethod("setTag", NBT_TAG_COMPOUND_CLASS);
        } catch (Exception exception) {
            exception.printStackTrace();
        }
    }

    public static NBTTag newTag() {
        try {
            return new NBTTag(NBT_TAG_COMPOUND_CLASS.newInstance());
        } catch (Exception exception) {
            throw new IllegalStateException(exception);
        }
    }

    public static NBTTag getItemNBT(ItemStack stack) {
        try {
            Object nmsStack = AS_NMS_COPY_METHOD.invoke(null, stack);

            Object tag = GET_TAG_METHOD.invoke(nmsStack);

            return tag != null ? new NBTTag(tag) : newTag();
        } catch (Exception exception) {
            throw new IllegalStateException(exception);
        }
    }

    private final Object handle;

    private NBTTag(Object tag) {
        this.handle = tag;
    }

    public boolean has(String key) {
        try {
            return (boolean) HAS_KEY_METHOD.invoke(this.handle, key);
        } catch (Exception exception) {
            exception.printStackTrace();

            return false;
        }
    }

    public void setString(String key, String value) {
        try {
            SET_STRING_METHOD.invoke(this.handle, key, value);
        } catch (Exception exception) {
            exception.printStackTrace();
        }
    }

    public void setInt(String key, int value) {
        try {
            SET_INT_METHOD.invoke(this.handle, key, value);
        } catch (Exception exception) {
            exception.printStackTrace();
        }
    }

    public void setTag(String key, NBTTag tag) {
        try {
            SET_METHOD.invoke(this.handle, key, tag.handle);
        } catch (Exception exception) {
            exception.printStackTrace();
        }
    }

    public String getString(String key) {
        try {
            return (String) GET_STRING_METHOD.invoke(this.handle, key);
        } catch (Exception exception) {
            exception.printStackTrace();

            return null;
        }
    }

    public int getInt(String key) {
        try {
            return (int) GET_INT_METHOD.invoke(this.handle, key);
        } catch (Exception exception) {
            exception.printStackTrace();

            return 0;
        }
    }

    public NBTTag getTag(String key) {
        try {
            return new NBTTag(GET_COMPOUND_METHOD.invoke(this.handle, key));
        } catch (Exception exception) {
            exception.printStackTrace();

            return null;
        }
    }

    public Object getHandle() {
        return this.handle;
    }

    public ItemStack apply(ItemStack stack) {
        try {
            Object nmsStack = AS_NMS_COPY_METHOD.invoke(null, stack);

            SET_TAG_METHOD.invoke(nmsStack, this.handle);

            return (ItemStack) AS_BUKKIT_MIRROR_METHOD.invoke(null, nmsStack);
        } catch (Exception exception) {
            exception.printStackTrace();

            return null;
        }
    }

}