Using AbstractElementTagProcessor tag body is created using modelFactory.createOpenElementTag and other methods. It is hard to create html layout using JAVA API. What if I create mini html template and in TagProcessor i will use String renderedBody = templateEngine.process(new Context(...)) and received rendered string (body html) pass as model.add(modelFactory.createText(renderedBody)). In this case it is simpler to support tag body html. What about performance? Maybe my solution has many cons?