Retrieve data from ModelAttribute method in the view - spring

Question

In my current spring project, I have a generic controller like this:
public class basicController<E> {
#Autowired
private basicService<E> serv;
protected Class<?> clazz;
public basicController(Class<?> clazz) {
this.clazz = clazz;
}
...
}
with a method like this:
#ModelAttribute("lista")
public List<E> populateList() {
return serv.lista();
}
I wonder if it's possible use the value for lista in a structure like that (in the html page):
<select class="form-control" th:name="...">
<option th:each="opt : ${lista}" th:value="${opt.getId()}"><span th:text="${opt}"/>
</option>
</select>
this page is mapped in the controllers with methods like that:
generic controller
#RequestMapping(value = "cadastra")
#PreAuthorize("hasPermission(#user, 'cadastra_'+#this.this.name)")
#Menu(label = "cadastra")
public String cadastra(Model model) throws Exception {
model.addAttribute("command", serv.newObject());
return "private/cadastra";
}
home controller (contains mappings for public views, among others things)
#RequestMapping(value = "/settings")
public String settings(Model model) throws Exception {
Authentication auth = SecurityContextHolder.getContext().getAuthentication();
model.addAttribute("usuario", auth.getName());
model.addAttribute("menu", MenuList.index());
model.addAttribute("settings", MenuList.settings());
return "private/settings";
}
#RequestMapping(value = "/profile")
public String profile(Model model) throws Exception {
Authentication auth = SecurityContextHolder.getContext().getAuthentication();
model.addAttribute("usuario", auth.getName());
model.addAttribute("menu", MenuList.index());
model.addAttribute("command", usuario(auth.getName()));
return "private/profile";
}
Anyone have any idea about this?

Answer 1

Ok, I just test and verify no extra configuration is needed for use the value from a ModelAttribute method. So, I just add methods like this in my controller:
#ModelAttribute("lista")
public List<E> populateListPagina() {
return serv.lista();
}
#ModelAttribute("classe")
public String getName() {
return clazz.getSimpleName();
}
and when I access any mapped view, I can use the value returned by this method in the way I like:
<tbody class="content">
<tr th:each="item : ${lista}">
<th></th>
<th th:each="coluna : ${campos}" th:text="${item[coluna]}"></th>
<th>
<div class="btn-group" role="group" aria-label="menu_item">
<button th:each="btn : ${menu_item}" type="button" class="btn btn-default link" th:attr="data-href=#{/__${classe}__/__${btn}__/__${item.getId()}__}" th:text="${btn}"></button>
</div>
</th>
</tr>
</tbody>

Answer 2

#ModelAttribute fires up before your controller methods do, and will disappear once your method runs I believe. So you won't have the object in the view anymore, it acts more like a #RequestParam.
However, you can try adding #SessionAttributes("lista") if you're using newer version of Spring ( I believe 4+). You have to be careful to make sure you close the session attributes though. To close, do what this guy did - link.