Spring使用Jackson处理json数据

1.搭建SpringMVC+Spring环境

2.配置web.xml、SpringMVC-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns="http://xmlns.jcp.org/xml/ns/javaee" 
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee 
    http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" 
    id="WebApp_ID" version="3.1">
    <!-- 定义Spring MVC的前端控制器 -->
  <servlet>
    <servlet-name>springmvc</servlet-name>
    <servlet-class>
        org.springframework.web.servlet.DispatcherServlet
    </servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>/WEB-INF/springmvc-config.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <!-- 让Spring MVC的前端控制器拦截所有请求 -->
  <servlet-mapping>
    <servlet-name>springmvc</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
  
  <!-- 编码过滤器 -->
  <filter>
        <filter-name>characterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
 </filter>
    <filter-mapping>
        <filter-name>characterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    
</web-app>

<?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:mvc="http://www.springframework.org/schema/mvc"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc-4.2.xsd     
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context-4.2.xsd">
        
    <!-- spring可以自动去扫描base-pack下面的包或者子包下面的java文件，
        如果扫描到有Spring的相关注解的类，则把这些类注册为Spring的bean -->
    <context:component-scan base-package="Controller"/>
    <!-- 设置配置方案  -->
    <mvc:annotation-driven/>
    <!-- 使用默认的Servlet来响应静态文件 -->
    <mvc:default-servlet-handler/>
    

    <!-- 视图解析器  -->
     <bean id="viewResolver"
          class="org.springframework.web.servlet.view.InternalResourceViewResolver"> 
        <!-- 前缀 -->
        <property name="prefix">
            <value>/WEB-INF/content/</value>
        </property>
        <!-- 后缀 -->
        <property name="suffix">
            <value>.jsp</value>
        </property>
    </bean>
    
</beans>

3.controller层

@Controller
@RequestMapping("/json")
public class BookController {
    
    private static final Log logger = LogFactory.getLog(BookController.class);
    
    // @RequestBody根据json数据，转换成对应的Object
    @RequestMapping(value="/testRequestBody")
    public void setJson(@RequestBody Book book,
            HttpServletResponse response) throws Exception{
        // ObjectMapper类是Jackson库的主要类。它提供一些功能将Java对象转换成对应的JSON格式的数据
        ObjectMapper mapper = new ObjectMapper();
        // 将book对象转换成json输出
        logger.info(mapper.writeValueAsString(book) );
        book.setAuthor("jackson");
        response.setContentType("text/html;charset=UTF-8");
        // 将book对象转换成json写出到客户端
        response.getWriter().println(mapper.writeValueAsString(book));
    }

}

4.实体类

public class Book implements Serializable {

    private Integer id;
    private String name;
    private String author;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    @Override
    public String toString() {
        return "Book [id=" + id + ", name=" + name + ", author=" + author + "]";
    }

}

5.表现层

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>测试接收JSON格式的数据</title>
<script type="text/javascript" src="js/jquery-1.11.0.min.js"></script>
<script type="text/javascript" src="js/json2.js"></script>
<script type="text/javascript">
$(document).ready(function(){
    testRequestBody();
});
function testRequestBody(){
    $.ajax(//"${pageContext.request.contextPath}/json/testRequestBody",// 发送请求的URL字符串。
            {
            url:"${pageContext.request.contextPath}/json/testRequestBody",
            dataType : "jsonp", // 预期服务器返回的数据类型。
               type : "post", //  请求方式 POST或GET
           contentType:"application/json", //  发送信息至服务器时的内容编码类型
           // 发送到服务器的数据。
           data:JSON.stringify({"id" : 1, "name" : "Spring MVC企业应用实战"}),
           async:  true , // 默认设置下，所有请求均为异步请求。如果设置为false，则发送同步请求
           // 请求成功后的回调函数。
           success :function(data){
              // console.log(data);
           //    data=eval('('+data+')');
              $("#id").html(data.id);
              $("#name").html(data.name);
              $("#author").html(data.author);
           },
           // 请求出错时调用的函数
           error:function(XMLHttpRequest, textStatus, errorThrown){
               alert(XMLHttpRequest.status);
               alert(XMLHttpRequest.readyState); 
               alert(textStatus); 
           }
    });
}
</script>
</head>
<body>
编号：<span id="id"></span><br>
书名：<span id="name"></span><br>
作者：<span id="author"></span><br>
</body>
</html>

运行结果：