响应Json数据

• 后端接收Json数据，使用@RequestBody注解，获得Json数据

  @Controller
  public class HelloController {
      @RequestMapping(path = "/hello")
      public String hello(@RequestBody String body) {
          System.out.println(body); //输出接收到的Json数据
          return "success";
      }
  }

• 将获得的Json数据，转换成Java对象

  1. 导入jar包

     <dependency>
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-databind</artifactId>
       <version>2.9.0</version>
     </dependency>
     <dependency>
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-core</artifactId>
       <version>2.9.0</version>
     </dependency>
     <dependency>
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-annotations</artifactId>
       <version>2.9.0</version>
     </dependency>

  2. 将接受的类型改为要接收的Java对象

     package com.oylong.controller;
     
     import org.springframework.stereotype.Controller;
     import org.springframework.web.bind.annotation.RequestBody;
     import org.springframework.web.bind.annotation.RequestMapping;
     
     @Controller
     public class HelloController {
         @RequestMapping(path = "/hello")
         public String hello(User user) {
             System.out.println(user); //输出Json的内容
             return "success";
         }
     }

     这里的前提是，接收的Json数据的key必须要于Java对象成员名称相对应

• 返回Json数据

  直接返回对象即可，只需要加一个@ResponseBody注解SpringMVC会自动将对象转换成Json数据

  @Controller
  public class HelloController {
      @RequestMapping(path = "/hello")
      public @ResponseBody User hello(User user) {
          System.out.println(user); //输出Json的内容
          return user;
      }
  }