1. 首先是对Spring mvc 进行xml配置

    其中annotation-driven是启动注解

2. 在maven 添加类

    
         
     
      2.7.3
     
    
    
         
     
      com.fasterxml.jackson.core
         
     
      jackson-core
         
     
      ${jackson.version}
     
    
    
         
     
      com.fasterxml.jackson.core
         
     
      jackson-databind
         
     
      ${jackson.version}
     
    
    
         
     
      com.fasterxml.jackson.core
         
     
      jackson-annotations
         
     
      ${jackson.version}
     
    

3. 创建Controller 处理json请求

package controller;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.http.MediaType;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestParam;import org.springframework.web.bind.annotation.ResponseBody;import javax.servlet.http.HttpSession;import java.util.HashMap;import java.util.Map;@Controllerpublic class JsonUserExistsController {    private Boolean flag ;    private String message;    @RequestMapping(value="json/test",            produces = MediaType.APPLICATION_JSON_VALUE)    public    @ResponseBody Map
    
         userchecking(@RequestParam Map
     
       params,HttpSession session){        Map
      
        json = new HashMap
       
        ();        String imageWord = params.get("imgcode");        String session_word = (String) session.getAttribute("image_word");        if(!session_word.equals(imageWord)){            flag = false;            message = "验证码错误";            json.put("flag",flag.toString());            json.put("message",message);            return json;        }    }    }
       
      
     
    

4. 结果

{"flag":"false","message":"验证码错误"}