final RequiredTextField ageMax = new RequiredTextField("ageMax");
ageMax.add(NumberValidator.range(1, 99));
ageMax.setType(Integer.class);
this.add(ageMax);
this.add(new SexeCategorieDropDownChoice("sexe").setRequired(true));
this.add(new NiveauDropDownChoice("niveau").setRequired(true));
this.add(new DropDownChoice("discipline", disciplineService.list(),
new DisciplineChoiceRenderer()));