@RequestBody 注解 如何接收 json 数据

RequestBody 官方指南：

• a method parameter should be bound to the value of the HTTP request body（方法参数名要与请求体的json数据的参数名对应）

• You convert the request body to the method argument by using an HttpMessageConverter（使用HttpMessageConverter转换器将请求体映射成方法参数）

HttpMessageConverter 转换器配置

• applicationContext.xml中配置jsonHttpMessageConverter转换器

<bean
        class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list>
                <ref bean="jsonHttpMessageConverter" />
            </list>
        </property>
    </bean>

    <bean id="jsonHttpMessageConverter"
        class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
         <property name="supportedMediaTypes">
            <list>
                <value>application/json;charset=UTF-8</value>
            </list>
        </property> 
    </bean>

ajax、java 应用实例

• js代码

 var jsonObj = {"openid":"xxx","username":"Ed sheeran","password":"123"};
          /*
              Jquery默认Content-Type为application/x-www-form-urlencoded类型
           */
          $.ajax({
              type: 'POST',
              url: "/login",
              dataType: "json",
              data: JSON.stringify(jsonObj),
              contentType : "application/json",
              success: function(data) {
                  console.log(data)
              },
              error: function() {
                  console.log("fucking error")
              }
          });

• Controller 代码

@Controller
public class LoginController {
  @PostMapping("/login")
  public void login(@RequestBody Form form){
      System.err.println(form);
  }
}