### Question:
MvelTemplateEngine extends TemplateEngine { @Override public String render(final ModelAndView modelAndView) { final CompiledTemplate compiledTemplate = loadTemplate(modelAndView.getViewName()); return (String) TemplateRuntime.execute(compiledTemplate, modelAndView.getModel()); } MvelTemplateEngine();  MvelTemplateEngine(final String prefix); @Override String render(final ModelAndView modelAndView); CompiledTemplate loadTemplate(String resourceName);  }### Answer:
@Test public void test_render() throws Exception { String templateVariable = "Hello Mvel!"; Map<String, Object> model = new HashMap<>(); model.put("message", templateVariable); String expected = String.format("<h1>%s</h1>", templateVariable); String actual = new MvelTemplateEngine().render(new ModelAndView(model, "hello.html")); assertEquals(expected, actual); }