SpringMVC_2_实操Controller

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Spring MVC起步 http://www.imooc.com/learn/47

spring 3.0 应用springmvc 构造RESTful URL 详细讲解 （转载）http://www.cnblogs.com/zzjjian333/archive/2012/11/14/rest1.html

（转载自：http://blog.csdn.net/yczz/article/details/5905893）

---4-1 配置文件-------------------------------------------
web.xml
2.4版本以上WEBAPP才默认支持EL表达式
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
 http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

<display-name>Spring MVC Study</display-name>
  <!-- Spring应用上下文， 理解层次化的ApplicationContext -->
  <context-param>
   <param-name>contextConfigLocation</param-name>
  <param-value>/WEB-INF/configs/spring/applicationContext*.xml</param-value>
  </context-param>
 
  <listener>
  <listener-class>
   org.springframework.web.context.ContextLoaderListener
  </listener-class>
  </listener>
 
  <!-- DispatcherServlet, Spring MVC的核心 可以有多个DispatcherServlet，来相应不同的请求-->
  <servlet>
  <servlet-name>mvc-dispatcher</servlet-name>
  <servlet-class> org.springframework.web.servlet.DispatcherServlet</servlet-class>
  <!-- DispatcherServlet对应的上下文配置， 默认为/WEB-INF/$servlet-name$-servlet.xml
   -->
  <init-param>
          <param-name>contextConfigLocation</param-name>
          <param-value>/WEB-INF/configs/spring/mvc-dispatcher-servlet.xml</param-value>
        </init-param>
  <load-on-startup>1</load-on-startup>
 </servlet>
 <servlet-mapping>
  <servlet-name>mvc-dispatcher</servlet-name>
     <!-- mvc-dispatcher拦截所有的请求-->
  <url-pattern>/</url-pattern>
 </servlet-mapping>
</web-app>

*****************************

mvc-dispatcher-servlet.xml：

DispatcherServlet, Spring MVC的核心 可以有多个DispatcherServlet，来相应不同的请求

<?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:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <!-- 本配置文件是工名为mvc-dispatcher的DispatcherServlet使用， 提供其相关的Spring MVC配置 -->

    <!-- 启用Spring基于annotation的DI, 使用户可以在Spring MVC中使用Spring的强大功能。 激活 @Required 
        @Autowired,JSR 250's @PostConstruct, @PreDestroy and @Resource 等标注 -->
    <context:annotation-config />

    <!-- DispatcherServlet上下文， 只管理@Controller类型的bean， 忽略其他型的bean, 如@Service -->
    <context:component-scan base-package="com.imooc.mvcdemo">
        <context:include-filter type="annotation"
            expression="org.springframework.stereotype.Controller" />
    </context:component-scan>

    <!-- HandlerMapping, 无需配置， Spring MVC可以默认启动。 DefaultAnnotationHandlerMapping 
        annotation-driven HandlerMapping -->

    <!-- 扩充了注解驱动，可以将请求参数绑定到控制器参数 -->
    <mvc:annotation-driven />

    <!-- 静态资源处理， css， js， imgs -->
    <mvc:resources mapping="/resources/**" location="/resources/" />


    <!-- 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>


    <!--200*1024*1024即200M resolveLazily属性启用是为了推迟文件解析，以便捕获文件大小异常 -->
    <bean id="multipartResolver"
        class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="maxUploadSize" value="209715200" />
        <property name="defaultEncoding" value="UTF-8" />
        <property name="resolveLazily" value="true" />
    </bean>

</beans>

applicationContext：

Spring应用上下文

<?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:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:annotation-config />

    <context:component-scan base-package="com.imooc.mvcdemo">
        <context:exclude-filter type="annotation"
            expression="org.springframework.stereotype.Controller" />
    </context:component-scan>
</beans>

 ------------------------------------------------------------

JSP：

　　1. JSTL

　　　　<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>）

　　2.EL表达式

　　　　<div class="course-title">${course.title}</div>

*JSTL和EL表达式完成了对象的输出

　　3.ＣＳＳ静态文件 （与配置文件中的静态资源处理相对应）

　　<link rel="stylesheet"
 href="<%=request.getContextPath()%>/resources/css/main.css"
 type="text/css" />

<%@ page language="java"
 contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!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" />
</head>
<body>

 <div id="main">

  <div class="newcontainer" id="course_intro">
   <div class="course-title">${course.title}</div>
   <div class="course_info">
    <div class="course-embed l">
     <div id="js-course-img" class="img-wrap">
      <img width="600" height="340" alt=""
       src="<%=request.getContextPath()%>/${course.imgPath}"
       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>${course.learningNum }</em></li>
      <li class="course_hour"><span>课程时长</span> <em
       class="ft-adjust"><span>${course.duration }</span>秒</em></li>
      <li><span>课程难度</span> <em>${course.levelDesc }</em></li>
     </ul>
    </div>
<!-- 
    <div class="course_intro">
     <div class="concerned_course add_concerned_course">
      <a href="javascript:void(0)" data-id="202"
       class="btn-add-follow js-btn-follow"> <i></i> <em
       class="concerned-icon">关注此课程</em>
      </a>
     </div>
     <div class="curse_btn">
      <a href="#">开始学习</a>
     </div>
    </div>
 -->   
   </div>
   <div class="course_list">
    <div class="outline">
     <h3 class="chapter_introduces">课程介绍</h3>
     <div class="course_shortdecription">${course.descr}</div>

     <h3 class="chapter_catalog">课程提纲</h3>
     <ul id="couList">
      <c:forEach items="${course.chapterList}" var="chapter">
       <li class="clearfix open"><a href="#">
         <div class="openicon"></div>
         <div class="outline_list l">
          <!-- <em class="outline_zt"></em> -->
          <h5 class="outline_name">${chapter.title }</h5>
          <p class="outline_descr">${chapter.descr }</p>
         </div>
       </a></li>
      </c:forEach>
     </ul>
    </div>

   </div>
  </div>

 </div>

</body>
</html>

---------------------------

Congroller：

*1.视图解析器的使用

　　internalresourceviewresolver  http://www.mkyong.com/spring-mvc/spring-mvc-internalresourceviewresolver-example/

　　SpringMVC介绍之视图解析器ViewResolver 

　　mvc-dispatcher-servlet.xml视图解析器配置

---

package com.imooc.mvcdemo.controller;

import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.io.FileUtils;
import org.apache.commons.lang.builder.ReflectionToStringBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;

import com.imooc.mvcdemo.model.Course;
import com.imooc.mvcdemo.service.CourseService;

@Controller
@RequestMapping("/courses")
// /courses/**
public class CourseController {
 

/*用来完成日志信息，在依赖管理中添加需要的API(  <dependency>
   <groupId>org.slf4j</groupId>
   <artifactId>slf4j-api</artifactId>
   <version>${slf4j.version}</version>
  </dependency>)

*/
 private static Logger log = LoggerFactory.getLogger(CourseController.class);

 private CourseService courseService;

 @Autowired //使用Spring的容器管理了依赖关系
 public void setCourseService(CourseService courseService) {
  this.courseService = courseService;
 }

 
 //传统方式URL：本方法将处理 /courses/view?courseId=123 形式的URL
 @RequestMapping(value="/view", method=RequestMethod.GET)
 public String viewCourse(Integer courseId,
   Model model) {
  
  log.debug("In viewCourse, courseId = {}", courseId);
  Course course = courseService.getCoursebyId(courseId);
  model.addAttribute(course);//JSP中通过${course.title}获取

//因为使用了SpringMVC的internalViewResolver(*1)，配置了前缀后缀，只返回页面名称就可以了
  return "course_overview";
 }
 }

---4-3 Controller-现代方式----------------------------------------------------------------------------

 1 通过@Controller 被SPRINGDespatcherServlet进行管理

　　(org.springframework.stereotype.Controller;)

2.处理controller的根URL，类级别的requestMapping

　　@RequestMapping("/courses")//

3.方法级别的requestMapping 本方法将处理 /courses/view?courseId=123 形式的URL,通过标签@RequestParam（"courseId"）取得request的参数

　　@RequestMapping(value="/view", method=RequestMethod.GET)

 　　public String viewCourse(@RequestParam（"courseId"）Integer courseId,    Model model) {

4.通过日志准确观察到绑定的行为

　　log.debug("In viewCourse, courseId = {}", courseId);

package com.imooc.mvcdemo.controller;
import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import org.apache.commons.io.FileUtils;
import org.apache.commons.lang.builder.ReflectionToStringBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;
import com.imooc.mvcdemo.model.Course;
import com.imooc.mvcdemo.service.CourseService;

@Controller//
@RequestMapping("/courses")//处理controller的根URL，类级别的requestMapping
// /courses/**
public class CourseController {
 
/*用来完成日志信息，在依赖管理中添加需要的API(  <dependency>
   <groupId>org.slf4j</groupId>
   <artifactId>slf4j-api</artifactId>
   <version>${slf4j.version}</version>
  </dependency>)
*/
 private static Logger log = LoggerFactory.getLogger(CourseController.class);
 private CourseService courseService;
 @Autowired //使用Spring的容器管理了依赖关系
 public void setCourseService(CourseService courseService) {
  this.courseService = courseService;
 }
 
 //方法级别的requestMapping 本方法将处理 /courses/view?courseId=123 形式的URL
 @RequestMapping(value="/view", method=RequestMethod.GET)
 public String viewCourse(@RequestParam（"courseId"）Integer courseId,
   Model model) {
  
  log.debug("In viewCourse, courseId = {}", courseId);//通过日志准确观察到绑定的行为
  Course course = courseService.getCoursebyId(courseId);
  model.addAttribute(course);//JSP中通过${course.title}获取
//因为使用了SpringMVC的internalViewResolver(*1)，配置了前缀后缀，只返回页面名称就可以了
  return "course_overview";
 }
}

 ---RESTful URL  本方法将处理 /courses/view2/123 形式的URL----------------------------------------------------

参照：spring 3.0 应用springmvc 构造RESTful URL 详细讲解  转载自http://blog.csdn.net/yczz/article/details/5905893

Spring通过@RequestMapping("/view2/{courseId}")和@PathVariable("courseId")绑定了入参

 //RESTful URL  本方法将处理 /courses/view2/123 形式的URL
 @RequestMapping("/view2/{courseId}",method=RequestMethod.GET)
 public String viewCourse2(@PathVariable("courseId") Integer courseId,
   Map<String, Object> model) {
  
  log.debug("In viewCourse2, courseId = {}", courseId);
  Course course = courseService.getCoursebyId(courseId);
  model.put("course",course);
  return "course_overview";
 }

---4-4 Controller-传统方式-----------------------------------------------------------

1.spring-mvc-study/pom.xml中引入servlet API

  <dependency>
   <groupId>javax.servlet</groupId>
   <artifactId>servlet-api</artifactId>
   <version>2.5</version>
  </dependency>

2.传统方法HttpServletRequest方式获取

 //方法级别的requestMapping，本方法将处理 /courses/view3?courseId=123 形式的URL
 @RequestMapping("/view3")
 public String viewCourse3(HttpServletRequest request) {
  
  Integer courseId = Integer.valueOf(request.getParameter("courseId"));  
  Course course = courseService.getCoursebyId(courseId);
  request.setAttribute("course",course);
  
  return "course_overview";
 }
 ---总结---

1.@Controller：通过Controller annotation声明一个controller

2.@RequestMapping (通常出现在类级别和方法级别，二者共同组合完成了对ＵＲＬ映射请求的拦截)通过RequestMapping annotation映射了URL和方法

3. URL template(@RequestParam and @PathVariable)：将ＵＲＬ路径中的参数绑定到controller method的入参

4.HttpServletRequest and/or HttpSession：也可以获取想要的结果