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4-7 JSON
work with JSON
JSON(JavaScript Object Notation) is a lightweight date interchange foramt.
.Restful Web Service
{ key1:value1
, key2:value2
, ... }
HTML-DATA-Apps{JSON},HTML和JSON是数据模型的不同表现形式。
SpringMVC ：ContentNegotiatingViewResolver来处理不同的数据呈现格式。
JSPView 人类
JsonView机器
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SpringMVC JSON的配置：
mvc-dispatcher-servlet.xml中加入如下代码；
配置defaultView，MappingJackson2JsonView把模型数据转换为JSON格式
<property name="defaultViews">
<list>
<!-- JSON View -->
<bean
class="org.springframework.web.servlet.view.json.MappingJackson2JsonView">
</bean>
</list>
</property>
<!-- 配置ViewResolver。 可以用多个ViewResolver。 使用order属性排序。 InternalResourceViewResolver放在最后。 --> <bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver"> <property name="order" value="1" /> <property name="mediaTypes"> <map> <entry key="json" value="application/json" /> <entry key="xml" value="application/xml" /> <entry key="htm" value="text/html" /> </map> </property> <property name="defaultViews"> <list> <!-- JSON View --> <bean class="org.springframework.web.servlet.view.json.MappingJackson2JsonView"> </bean> </list> </property> <property name="ignoreAcceptHeader" value="true" /> </bean> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" /> <property name="prefix" value="/WEB-INF/jsps/" /> <property name="suffix" value=".jsp" /> </bean>
pom.xml引用
<properties> <commons-lang.version>2.6</commons-lang.version> <slf4j.version>1.7.6</slf4j.version> <spring.version>4.1.3.RELEASE</spring.version> <jackson.version>2.5.4</jackson.version> </properties> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>${jackson.version}</version> </dependency>
3. controller
3.1 最简单方法@ResponseBody Course
@RequestMapping(value="/{courseId}",method=RequestMethod.GET)
public @ResponseBody Course getCourseInJson(@PathVariable Integer courseId){
return courseService.getCoursebyId(courseId);
}
3.2 ResponseEntity<Course>：ResponseEntity为SpringMVC为我们抽象的实体，使用泛型方式包裹了类
@PathVariable关联查询参数和方法参数
@RequestMapping(value="/jsontype/{courseId}",method=RequestMethod.GET)
此时就不需要引入@ResponseBody了。
return new ResponseEntity<Course>(course, HttpStatus.OK);构造方式为实际的模型数据和一个Http的状态
public ResponseEntity<Course> getCourseInJson2(@PathVariable Integer courseId){
Course course = courseService.getCoursebyId(courseId);
return new ResponseEntity<Course>(course, HttpStatus.OK);
}
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JSP通过JQUERY把JSON数据加载到页面
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>我不是真正的慕课网</title> <link rel="stylesheet" href="<%=request.getContextPath()%>/resources/css/main.css" type="text/css" /> <script type="text/javascript" src="<%=request.getContextPath()%>/resources/js/jquery-1.11.3.min.js"></script> </head> <script> jQuery(function($){ var urlStr = "<%=request.getContextPath()%>/courses/<%=request.getParameter("courseId")%>"; //alert("Before Call:"+urlStr); $.ajax({ method: "GET", url: urlStr, success:function(data,status,jqXHR){ //alert("Success:"+data); var course = data; var path = "<%=request.getContextPath()%>/"; $(".course-title").html(course.title); $(".course_video").attr("src", path+course.imgPath); $("#learningNum").text(course.learningNum); $("#duration").text(course.duration); $("#levelDesc").text(course.levelDesc); $(".course_shortdecription").html(course.descr); var chapterList = course.chapterList; var chapter; for(var i = 0;i<chapterList.length;i++){ chapter = chapterList[i]; var liObj = $("li",$("#chapterTemplate")).clone(); $(".outline_name", liObj).text(chapter.title); $(".outline_descr", liObj).text(chapter.descr); liObj.appendTo("#couList"); }// ~ end for } }); // end ajax }); </script> <body> <div id="main"> <div class="newcontainer" id="course_intro"> <div class="course-title"></div> <div class="course_info"> <div class="course-embed l"> <div id="js-course-img" class="img-wrap"> <img width="600" height="340" alt="" class="course_video" /> </div> <div id="js-video-wrap" class="video" style="display: none"> <div class="video_box" id="js-video"></div> </div> </div> <div class="course_state"> <ul> <li><span>学习人数</span> <em id="learningNum"></em></li> <li class="course_hour"><span>课程时长</span> <em class="ft-adjust"><span id="duration"></span>秒</em></li> <li><span>课程难度</span> <em id="levelDesc"></em></li> </ul> </div> </div> <div class="course_list"> <div class="outline"> <h3 class="chapter_introduces">课程介绍</h3> <div class="course_shortdecription"></div> <h3 class="chapter_catalog">课程提纲</h3> <ul id="couList"> </ul> </div> </div> </div> </div> <div id="chapterTemplate" style="display:none"> <li class="clearfix open"><a href="#"> <div class="openicon"></div> <div class="outline_list l"> <h5 class="outline_name"></h5> <p class="outline_descr"></p> </div> </a></li> </div> </body> </html>
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总结：SpringMVC同JSON协同工作的内容
SpringMVC ：ContentNegotiatingViewResolver来将不同的数据呈现请求转化成不同的View。把相同格式的数据分发到不同的呈现请求
ResponseEntity 通过泛型类，处理返回结果，将返回的数据模型包裹在这个类之中就可以把模型数据转换为JSON格式
更简便的方式@ResponseBody/@RequestBody方式
==5 Summary======================================
宏观：MVC的核心思想
Structure：
Details：
Conroller编写
数据绑定
文件上传
JSON协同
讲解的知识点：
