@RequestBody and @ResponseBody annotations in Spring

@RequestBody and @ResponseBody annotations in Spring

Can someone explain the @RequestBody and @ResponseBody annotations in Spring 3? What are they for? Any examples would be great.

There is a whole Section in the docs called 16.3.3.4 Mapping the request body with the @RequestBody annotation. And one called 16.3.3.5 Mapping the response body with the @ResponseBody annotation. I suggest you consult those sections. Also relevant: @RequestBody javadocs, @ResponseBody javadocs

Usage examples would be something like this:

Using a JavaScript-library like JQuery, you would post a JSON-Object like this:

{ "firstName" : "Elmer", "lastName" : "Fudd" }

Your controller method would look like this:

// controller
@ResponseBody @RequestMapping("/description")
public Description getDescription(@RequestBody UserStats stats){
    return new Description(stats.getFirstName() + " " + stats.getLastname() + " hates wacky wabbits");
}

// domain / value objects
public class UserStats{
    private String firstName;
    private String lastName;
    // + getters, setters
}
public class Description{
    private String description;
    // + getters, setters, constructor
}

Now if you have Jackson on your classpath (and have an <mvc:annotation-driven> setup), Spring would convert the incoming JSON to a UserStats object from the post body (because you added the @RequestBody annotation) and it would serialize the returned object to JSON (because you added the @ResponseBody annotation). So the Browser / Client would see this JSON result:

{ "description" : "Elmer Fudd hates wacky wabbits" }

See this previous answer of mine for a complete working example: https://stackoverflow.com/a/5908632/342852

Note: RequestBody / ResponseBody is of course not limited to JSON, both can handle multiple formats, including plain text and XML, but JSON is probably the most used format.

---

Update

Ever since Spring 4.x, you usually won't use @ResponseBody on method level, but rather @RestController on class level, with the same effect.

Here is a quote from the official Spring MVC documentation:

@RestController is a composed annotation that is itself meta-annotated with @Controller and @ResponseBody to indicate a controller whose every method inherits the type-level @ResponseBody annotation and, therefore, writes directly to the response body versus view resolution and rendering with an HTML template.

@RequestBody : Annotation indicating a method parameter should be bound to the body of the HTTP request.

For example:

@RequestMapping(path = "/something", method = RequestMethod.PUT)
public void handle(@RequestBody String body, Writer writer) throws IOException {
    writer.write(body);
}

@ResponseBody annotation can be put on a method and indicates that the return type should be written straight to the HTTP response body (and not placed in a Model, or interpreted as a view name).

For example:

@RequestMapping(path = "/something", method = RequestMethod.PUT)
public  @ResponseBody String helloWorld() {
    return "Hello World";
}  

Alternatively, we can use @RestController annotation in place of @Controller주석입니다.이 기능을 사용하면 이 기능을 사용할 필요가 없어집니다.@ResponseBody.

자세한 것은

Java 컨트롤러의 메서드의 예를 다음에 나타냅니다.

@RequestMapping(method = RequestMethod.POST)
@ResponseBody
public HttpStatus something(@RequestBody MyModel myModel) 
{
    return HttpStatus.OK;
}

@RequestBody 주석을 사용하면 특정 콜을 처리하기 위해 시스템에서 작성한 모델에 값을 매핑할 수 있습니다.@ResponseBody를 사용하면 요청이 생성된 장소로 어떤 것이든 다시 보낼 수 있습니다.커스텀 파서 등을 작성하지 않아도, 어느 쪽도 간단하게 매핑 할 수 있습니다.

package com.programmingfree.springshop.controller;

import java.util.List;

import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.programmingfree.springshop.dao.UserShop;
import com.programmingfree.springshop.domain.User;


@RestController
@RequestMapping("/shop/user")
public class SpringShopController {

 UserShop userShop=new UserShop();

 @RequestMapping(value = "/{id}", method = RequestMethod.GET,headers="Accept=application/json")
 public User getUser(@PathVariable int id) {
  User user=userShop.getUserById(id);
  return user;
 }


 @RequestMapping(method = RequestMethod.GET,headers="Accept=application/json")
 public List<User> getAllUsers() {
  List<User> users=userShop.getAllUsers();
  return users;
 }


}

위의 예에서는 모든 사용자 및 특정 ID 세부 정보가 표시됩니다.ID와 이름을 모두 사용하고 싶습니다.

1) localhost: 8093/plejson/shop/user <--- 이 링크는 모든 사용자 세부사항을 표시합니다.
2) localhost: 8093/plejson/shop/user/11 <---링크 수단으로 11을 사용하면 특정 사용자 11의 상세 내용이 표시됩니다.

이제 아이디와 이름을 모두 사용하고 싶다.

localhost: 8093/plejson/shop/user/11/raju <--------------------------------------------------------------------------------------------------------------------

언급URL : https://stackoverflow.com/questions/11291933/requestbody-and-responsebody-annotations-in-spring