What is the RESTful way of creating/updating multiple resources - rest

Question

Using Spring MVC on the server, we have your basic REST API:
#Controller
#RequestMapping(value="/entities")
public class EntityController
{
//GET /entities
#RequestMapping(method=RequestMethod.GET)
#ResponseBody
public List<Entity> getEntities()
...
//GET /entities/{id}
#RequestMapping(value="/{id}", method=RequestMethod.GET)
#ResponseBody
public Entity getEntity(#PathVariable Long id)
...
//POST /entities
#RequestMapping(method=RequestMethod.POST, consumes="application/json")
#ResponseBody
public Entity createEntity(#RequestBody Entity entity)
...
//PUT /entities
#RequestMapping(method=RequestMethod.PUT, consumes="application/json")
#ResponseBody
public Entity updateEntity(#RequestBody Entity entity)
...
}
This all works just fine. Now I'm wanting to be able to create or update mutliple Entitys with one request. My first thought was to add this:
#RequestMapping(method=RequestMethod.PUT, consumes="application/json")
#ResponseBody
public List<Entity> updateEntities(#RequestBody List<T> entities)
It would have the same URL as the updateEntity but handle lists ([...]). The updateEntity would handle a single object ({...}). However, on server startup I got the following error:
java.lang.IllegalStateException: Ambiguous mapping found. Cannot map 'entityController' bean method public java.util.List<foo.bar.Entity> foo.bar.EntityController.updateEntities(java.util.List<foo.bar.Entity>) to {[/entities],methods=[PUT],params=[],headers=[],consumes=[application/json],produces=[],custom=[]}: There is already 'entityController' bean method public foo.bar.Entity foo.bar.EntityController.updateEntity(foo.bar.Entity) mapped.
So, from what I gather, Spring doesn't like two different methods with the same #RequestMapping, even though the #RequestBody is different.
This leads me to two questions. First, am I going about this the correct RESTful way? Am I in line with RESTful principles when I'm doing a PUT to the same URL and just allowing the request body to be a single object or a list? Would there be another correct way of doing this that Spring would like? (Ok, so the first question was actually three...)
The 2nd question is if there is something I can add to the #RequestMapping annotation that would differentiate the two methods enough, but keep the same REST API?
Thanks for any light you can shed on this.

Answer 1

#JsonIgnoreProperties(ignoreUnknown = true) for each model
I have done on this way...with Two model: User and Tree
#RequestMapping(value = "/users/testBean", method = RequestMethod.POST, consumes={"application/json","application/xml"}, produces={"application/json","application/xml"})
public #ResponseBody List<User> testBean(#RequestBody Object object) {
System.out.println("testBean called");
System.out.println(object.toString());
ObjectMapper mapper=new ObjectMapper();
User user =mapper.convertValue(object, User.class);
Tree tree =mapper.convertValue(object, Tree.class);
System.out.println("User:"+user.toString());
System.out.println("Tree:"+tree.toString());
return userService.findAll();
}