public class YourWindow extends GuiWindow<YourCache> {

    public YourWindow(GuiCluster<YourCache> guiCluster, String key, int size) {
        super(guiCluster, key, size);
    }

    @Override
    public void onInit() {
        //Called on initialization. Used to register Buttons.
        registerButton();
    }

    @Override
    public void onUpdateSync(GuiUpdate<YourCache> guiUpdate) {
        //Updated sync
    }

    @Override
    public void onUpdateAsync(GuiUpdate<YourCache> update) {
        //Updated async
    }

}