MyImmutableMapInventoryData

public class MyImmutableMapInventoryData extends AbstractImmutableData<MyImmutableMapInventoryData, MyMapInventoryData> {
    private Map<String, Map<Integer, ItemStack>> mapinventory;

    public MyImmutableMapInventoryData(Map<String, Map<Integer, ItemStack>> mapinventory) {
        this.mapinventory = mapinventory;
        registerGetters();
    }

    @Override
    protected void registerGetters() {
        registerFieldGetter(ToolCore.MAPINVENTORY, () -> this.mapinventory);
        registerKeyValue(ToolCore.MAPINVENTORY, this::mapinventory);
    }

    public ImmutableMapValue<String, Map<Integer, ItemStack>> mapinventory() {
        return Sponge.getRegistry().getValueFactory().createMapValue(ToolCore.MAPINVENTORY, mapinventory).asImmutable();
    }

    @Override
    public MyMapInventoryData asMutable() {
        return new MyMapInventoryData(mapinventory);
    }

    @Override
    public int getContentVersion() {
        return 1;
    }

    @Override
    public DataContainer toContainer() {
        return super.toContainer().set(ToolCore.MAPINVENTORY.getQuery(), this.mapinventory);
    }
}