The inventory component of our sample property management system deals with rooms. In Chapter 3, The First Endpoint, we built an endpoint to access rooms. Let's take a look at how to define an endpoint for creating new resources:

@RestController
@RequestMapping("/rooms")
public class RoomsResource {

  @RequestMapping(method = RequestMethod.POST)
  public ApiResponse addRoom(@RequestBody RoomDTO room) {
    Room newRoom = createRoom(room);
    return new ApiResponse(Status.OK, new RoomDTO(newRoom));
  }
}

We've added a new method to our RoomsResource class to handle the creation of new rooms. As described in Chapter 3, The First Endpoint, @RequestMapping is used to map requests to the Java method. Here, we map POST requests to addRoom().

We pass the new room as a @RequestBody annotation. This annotation instructs Spring to map the body of the incoming web request to the method parameter. Jackson...