SpringMVC返回json數據完整配置如下。

1.SpringMVC 配置文件如下:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org.schema/aop"
    xmlns:tx="http://www.springframework.org.schema/tx"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="
            http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context-3.0.xsd
            http://www.springframework.org/schema/tx
            http://www.springframework.org/schema/tx/spring-tx.xsd
            http://www.springframework.org/schema/aop
            http://www.springframework.org/schemma/aop/spring-aop.xsd
            http://www.springframework.org/schema/mvc
            http://www.springframework.org/schema/mvc/spring-mvc.xsd
">
    <!-- 註冊mvc註解驅動  讓容器創建HttpMessageConverter 對象 ..-->
    <mvc:annotation-driven />
    <!-- 註冊組件掃描器 -->
    <context:component-scan base-package="com.evecom.json"></context:component-scan>
    <!-- 視圖頁面配置 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix">
            <value>/WEB-INF/views/</value>
        </property>
        <property name="suffix">
            <value>.jsp</value>
        </property>
    </bean>



</beans>

2.利用maven管理json數據相關jar包，這裏請注意。不要自己去百度上找jar包。因爲有些個人博客下載需要積分。而且找得過程與配置過程也比較心累(經常出錯)。有這麼好的東西幹嘛不用。如下。 在pom.xml文件中添加如下依賴關係..(我是這樣叫的).

   <!-- json -->

   <dependency>
     <groupId>commons-beanutils</groupId>
     <artifactId>commons-beanutils</artifactId>
     <version>1.9.2</version>
    </dependency>

    <dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-collections4</artifactId>
     <version>4.0</version>
    </dependency>

    <dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-lang3</artifactId>
      <version>3.6</version>
     </dependency>

     <dependency>
      <groupId>net.sf.ezmorph</groupId>
      <artifactId>ezmorph</artifactId>
      <version>1.0.6</version>
     </dependency>



     <dependency>
      <groupId>commons-logging</groupId>
      <artifactId>commons-logging</artifactId>
      <version>1.2</version>
     </dependency>
    <!-- json -->

    <!-- json obj -->

    <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
   <dependency>
     <groupId>com.fasterxml.jackson.core</groupId>
     <artifactId>jackson-databind</artifactId>
     <version>2.9.1</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
  <dependency>
     <groupId>com.fasterxml.jackson.core</groupId>
     <artifactId>jackson-core</artifactId>
     <version>2.9.1</version>
  </dependency>

    <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->
  <dependency>
     <groupId>com.fasterxml.jackson.core</groupId>
     <artifactId>jackson-annotations</artifactId>
     <version>2.9.1</version>
   </dependency>



    <!-- json obj -->

3.java代碼咯。(Controller)

這裏我是用springMVC中的註解形式…

@Controller
@RequestMapping("userinfo")
public class UserInfoList {

    @RequestMapping("/list")
    public void userInfoList(HttpServletResponse response,UserInfo userInfo)throws IOException {
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("name", userInfo.getName());
        map.put("age", userInfo.getAge());
        map.put("sex", userInfo.getSex());

        JSONObject myJson = JSONObject.fromObject(map);

        System.out.println("有走到這個方法");
        String jsonString = myJson.toString();

        response.setCharacterEncoding("utf-8");

        PrintWriter out = response.getWriter();
        out.print(jsonString);
        out.close();


    }
    //請求參數作爲路徑參數。。。
    @RequestMapping("/{rname}/{rage}/login.do")
    public ModelAndView loginAction(@PathVariable("rname") String rname,
            @PathVariable int rage) {

        ModelAndView modelAndView = new ModelAndView("user");
        modelAndView.addObject("name", rname);
        modelAndView.addObject("age", rage);
        return modelAndView;

    }
    //,produces="text/html;charset=utf-8" 設置編碼格式。。。
    @RequestMapping(value="/myajax.do")
    @ResponseBody
    public Object doAjax() {
//      return 123.456; 
        // 這樣更像 json 數據.....
//      // list <UserInfo> list =  
        Map<String, Object> responseM = new HashMap<String, Object>();
        Map<String, UserInfo> map = new HashMap<String, UserInfo>();
        map.put("user1",new UserInfo("張三", "男", 23));
        map.put("user2", new UserInfo("李四", "男", 24));
        map.put("user3", new UserInfo("韓梅梅", "女", 25));
        responseM.put("data", map);
        responseM.put("state", "success");
        return responseM;
    }

}

4.前端頁面使用ajax 做網絡請求。所以。這裏我們下載jQuery代碼並將它添加到工程中去。

index.jsp頁面如下

<script type="text/javascript" src="js/jquery-3.2.1.min.js"></script>
<script>
 $(function(){
     $("#ajax_r").click(function(){
        $.ajax({
            url:"userinfo/list.do",
            data:{
                name:"北京",
                age:23,
                sex:"男"
            },
            success:function(data){
                // 解析字符串.
            var myJson = eval("(" + data + ")");
                console.log(myJson.name);
                console.log(myJson.sex);

            },
            error:function(){
                alert("請求出錯");
            }
        });
     });

     $("#ajax_obj").click(function(){
        $.ajax({
            url:"userinfo/myajax.do",
            data:{

            },
            success:function(data){
                // 解析字符串.
                //var myJson = eval("(" + data + ")");
                //console.log(myJson);
                //console.log(data.name + " " + data.age + " " + data.sex);
                console.log(data);
            },
            error:function(){
                alert("請求出錯!");
            }
        });
     });

 });
</script>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>ajax請求測試</title>
</head>
<body>

 <button id="ajax_r">提交ajax請求</button>



 <a href="test/other.do"> 請求轉發</a>



</body>
</html>

到這裏如果配置沒有出錯的話可以看到這樣。算是基本完成了。。可以請求得到數據了。

哦。這裏說一下。我也是初學者。僅在此發個博客做個筆記。如果有什麼理解錯誤的地方，歡迎指出。一起學習哈