Spring mvc 构造RESTful URL 详细讲解（spring 3.0 应用）

详细讲解spring rest使用,简单例子如下:

 /blog/ 1   HTTP GET =>    得到id =  1 的blog
 /blog/1   HTTP DELETE => 删除 id =  1 的blog
 /blog/1   HTTP PUT  =>   更新id =  1 的blog
 /blog     HTTP POST =>   新增BLOG

首先，我们带着如下三 个问题 查看本文。
1. 如何在java构造没有扩展名的RESTful url,如 /forms/1,而不是 /forms/1.do

2. 由于我们要构造没有扩展名的url本来是处理静态资源的容器映射的，现在被我们的spring占用了，冲突怎么解决?

3. 浏览器的form标签不支持提交delete,put请求，如何曲线解决?

 

spring mvc rest 实现

spring mvc的resturl是通过@RequestMapping 及@PathVariable annotation提供的,通过如@RequestMapping(value="/blog /{id}",method=RequestMethod.DELETE)即可处理/blog/1 的delete请求.

 @RequestMapping (value= "/blog/{id}" ,method=RequestMethod.DELETE)
 public  ModelAndView delete( @PathVariable  Long id,HttpServletRequest request,HttpServletResponse response) {
     blogManager.removeById(id);
     return   new  ModelAndView(LIST_ACTION);
 }

@RequestMapping @PathVariable如果URL中带参数，则配合使用，如

 @RequestMapping (value= "/blog/{blogId}/message/{msgId}" ,method=RequestMethod.DELETE)
 public  ModelAndView delete( @PathVariable ( "blogId" ) Long blogId, @PathVariable ( "msgId" ) Long msgId,HttpServletRequest request,HttpServletResponse response) {
 }

 

 spring rest配置指南

1. spring mvc web.xml配置

 <!-- 该servlet为tomcat,jetty等容器提供,将静态资 源映射从/改为/static/目录，如原来访问 http://localhost/foo.css ,现在http://localhost /static/foo.css -->
 < servlet-mapping >
     < servlet-name > default </ servlet-name >
     < url-pattern > /static/* </ url-pattern >
 </ servlet-mapping >
 < servlet >
     < servlet-name > springmvc </ servlet-name >
     < servlet-class > org.springframework.web.servlet.DispatcherServlet </ servlet-class >
     < load-on-startup > 1 </ load-on-startup >
 </ servlet >

 <!-- URL重写filter,用于将访问静态资源http://localhost/foo.css 转为http://localhost/static/foo.css -->
 < filter >
     < filter-name > UrlRewriteFilter </ filter-name >
     < filter-class > org.tuckey.web.filters.urlrewrite.UrlRewriteFilter </ filter-class >
     < init-param >
             < param-name > confReloadCheckInterval </ param-name >
             < param-value > 60 </ param-value >
         </ init-param >
     < init-param >
                 < param-name > logLevel </ param-name >
                 < param-value > DEBUG </ param-value >
         </ init-param >
 </ filter >
 < filter-mapping >
     < filter-name > UrlRewriteFilter </ filter-name >
     < url-pattern > /* </ url-pattern >
 </ filter-mapping >

 <!-- 覆盖default servlet的/, springmvc servlet将处理原来处理静态资源的映射 -->
 < servlet-mapping >
     < servlet-name > springmvc </ servlet-name >
     < url-pattern > / </ url-pattern >
 </ servlet-mapping >

 <!-- 浏览器不支持put,delete等method,由该filter将/blog?_method=delete转换为标准的http delete方法 -->
 < filter >
     < filter-name > HiddenHttpMethodFilter </ filter-name >
     < filter-class > org.springframework.web.filter.HiddenHttpMethodFilter </ filter-class >
 </ filter >

 < filter-mapping >
     < filter-name > HiddenHttpMethodFilter </ filter-name >
     < servlet-name > springmvc </ servlet-name >
 </ filter-mapping >

 

 

2. webapp/WEB-INF/springmvc-servlet.xml配置,使用如下两个class激活@RequestMapping annotation

 <bean  class = "org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" />
 <bean class = "org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" />

 

完整配置

 <beans  default -autowire= "byName"    >

     <!-- 自动搜索@Controller 标注的类 -->
     <context:component-scan base-package = "com.**.controller" />

     <bean class = "org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" />

     <bean class = "org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" />

     <!-- Default ViewResolver -->
     <bean id="viewResolver"   class = "org.springframework.web.servlet.view.InternalResourceViewResolver" >
         <property name="viewClass"  value= "org.springframework.web.servlet.view.JstlView" />
         <property name="prefix"  value= "/pages" />
         <property name="suffix"  value= ".jsp" ></property>
     </bean>

     <bean id="messageSource"   class = "org.springframework.context.support.ResourceBundleMessageSource"  p:basename= "i18n/messages" />

     <!-- Mapping exception to the handler view -->
     <bean id="exceptionResolver"   class = "org.springframework.web.servlet.handler.SimpleMappingExceptionResolver" >
         <!-- to /commons/error.jsp -->
         <property name="defaultErrorView"  value= "/commons/error" />
         <property name="exceptionMappings" >
             <props>
             </props>
         </property>
     </bean>

 </beans>

 

 

3. Controller编写

 /**
  * @RequestMapping("/userinfo") 具有层次关系，方法级的将在类一级@RequestMapping之一,
  * 如下面示例, 访问方法级别的@RequestMapping("/new"),则URL为 /userinfo/new
  */
 @Controller
 @RequestMapping ( "/userinfo" )
 public   class  UserInfoController  extends  BaseSpringController{
     //默认多列排序,example: username desc,createTime asc
     protected   static   final  String DEFAULT_SORT_COLUMNS =  null ;

     private  UserInfoManager userInfoManager;

     private   final  String LIST_ACTION =  "redirect:/userinfo" ;

     /**
      * 通过spring自动注入
      **/
     public   void  setUserInfoManager(UserInfoManager manager) {
         this .userInfoManager = manager;
     }

     /** 列表 */
     @RequestMapping
     public  ModelAndView index(HttpServletRequest request,HttpServletResponse response,UserInfo userInfo) {
         PageRequest<Map> pageRequest = newPageRequest(request,DEFAULT_SORT_COLUMNS);
         //pageRequest.getFilters(); //add custom filters

         Page page = this .userInfoManager.findByPageRequest(pageRequest);
         savePage(page,pageRequest,request);
         return   new  ModelAndView( "/userinfo/list" , "userInfo" ,userInfo);
     }

     /** 进入新增 */
     @RequestMapping (value= "/new" )
     public  ModelAndView _new(HttpServletRequest request,HttpServletResponse response,UserInfo userInfo)  throws  Exception {
         return   new  ModelAndView( "/userinfo/new" , "userInfo" ,userInfo);
     }

     /** 显示 */
     @RequestMapping (value= "/{id}" )
     public  ModelAndView show( @PathVariable  Long id,HttpServletRequest request,HttpServletResponse response)  throws  Exception {
         UserInfo userInfo = (UserInfo)userInfoManager.getById(id);
         return   new  ModelAndView( "/userinfo/show" , "userInfo" ,userInfo);
     }

     /** 编辑 */
     @RequestMapping (value= "/{id}/edit" )
     public  ModelAndView edit( @PathVariable  Long id,HttpServletRequest request,HttpServletResponse response)  throws  Exception {
         UserInfo userInfo = (UserInfo)userInfoManager.getById(id);
         return   new  ModelAndView( "/userinfo/edit" , "userInfo" ,userInfo);
     }

     /** 保存新增 */
     @RequestMapping (method=RequestMethod.POST)
     public  ModelAndView create(HttpServletRequest request,HttpServletResponse response,UserInfo userInfo)  throws  Exception {
         userInfoManager.save(userInfo);
         return   new  ModelAndView(LIST_ACTION);
     }

     /** 保存更新 */
     @RequestMapping (value= "/{id}" ,method=RequestMethod.PUT)
     public  ModelAndView update( @PathVariable  Long id,HttpServletRequest request,HttpServletResponse response)  throws  Exception {
         UserInfo userInfo = (UserInfo)userInfoManager.getById(id);
         bind(request,userInfo);
         userInfoManager.update(userInfo);
         return   new  ModelAndView(LIST_ACTION);
     }

     /** 删除 */
     @RequestMapping (value= "/{id}" ,method=RequestMethod.DELETE)
     public  ModelAndView delete( @PathVariable  Long id,HttpServletRequest request,HttpServletResponse response) {
         userInfoManager.removeById(id);
         return   new  ModelAndView(LIST_ACTION);
     }

     /** 批量删除 */
     @RequestMapping (method=RequestMethod.DELETE)
     public  ModelAndView batchDelete( @RequestParam ( "items" ) Long[] items,HttpServletRequest request,HttpServletResponse response) {

         for ( int  i =  0 ; i < items.length; i++) {

             userInfoManager.removeById(items[i]);
         }
         return   new  ModelAndView(LIST_ACTION);
     }

 }

 

 

上面是rapid-framework新版本生成器生成的代码,以后也将应用此规则,rest url中增删改查等基本方法与Controller的方法映射规则

 /userinfo           => index()
 /userinfo/new        => _new()
 /userinfo/{id}      => show()
 /userinfo/{id}/edit         => edit()
 /userinfo   POST        => create()
 /userinfo/{id}  PUT => update()
 /userinfo/{id}  DELETE  => delete()
 /userinfo   DELETE      => batchDelete()

 注(不使用 /userinfo/add  => add() 方法是由于add这个方法会被maxthon浏览器当做广告链接过滤掉,因为包含ad字符)

 

4. jsp 编写

 < form:form   action = "${ctx}/userinfo/${userInfo.userId}"   method = "put" >
 </ form:form >

 生成的html内容如下, 生成一个hidden的_method=put,并于web.xml中的HiddenHttpMethodFilter配合使用，在服务端将post请求改为put请求

 <form id= "userInfo"  action= "/springmvc_rest_demo/userinfo/2"  method= "post" >
     <input type="hidden"  name= "_method"  value= "put" />
 </form>

 

另外一种方法是你可以使用ajax发送put,delete请求.

 

5. 静态资源的URL重写

   如上我们描述，现因为将default servlet映射至/static/的子目录，现我们访问静态资源将会带一个/static/前缀.

   如 /foo.gif, 现在访问该文件将是 /static/foo.gif.
   那如何避免这个前缀呢，那就是应用URL rewrite,现我们使用 http://tuckey.org/urlrewrite/ , 重写规则如下

 

Xml代码

< urlrewrite >
    <!-- 访问jsp及jspx将不rewrite url,其它.js,.css,.gif等将重写,如 /foo.gif => /static/foo.gif -->
    < rule >
        < condition   operator = "notequal"   next = "and"   type = "request-uri" > .*.jsp </ condition >
        < condition   operator = "notequal"   next = "and"   type = "request-uri" > .*.jspx </ condition >
        < from > ^(/.*\..*)$ </ from >
        < to > /static$1 </ to >
    </ rule >
</ urlrewrite >