RenderContext context = new BaseRenderContext();
InitialRenderContext initialContext = new BaseInitialRenderContext();
initialContext.set(RenderContext.INPUT_LOCALE, new Locale("atabaque", ""));
initialContext.set(RenderContext.OUTPUT_LOCALE, new Locale("atabaque", ""));
Filter filter = new UnderlineFilter();
filter.setInitialContext(initialContext);
RenderEngine engineWithContext = new BaseRenderEngine(initialContext);
return engineWithContext.render(arg, context);
}