前些日子看了一篇關于在Spring 2中整合DWR 2的文章《AJAX, DWR and Spring》。最近,想動手試一下,就下載其源代碼回來看看,依葫蘆畫瓢做了一遍。在運行時,得到XML驗證錯誤。經過一翻折騰,終于把問題解決。
Spring 2基于XML Schema的配置
眾所周知,Spring 2通過XML Schema配置方式極大地簡化的其配置,而且使得第三方擴展變為可能。配置如下代碼所示:
< beans xmlns ="http://www.springframework.org/schema/beans"
? ? xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
? ? xsi:schemaLocation ="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd" > ? ?
? ??
? ? <!-- <bean /> definitions here -->
? ??
</ beans >
不知大家有沒有想過spring-beans-2.0.xsd位置在那里?其實,大家可以用Eclipse打開Spring的jar包,展開META-INF,并雙擊打開其中的spring.schemas文件,內容如下:
http\://www.springframework.org/schema/tool/spring-tool- 2.0 .xsd = org/springframework/beans/factory/xml/spring-tool- 2.0 .xsd
http\://www.springframework.org/schema/util/spring-util- 2.0 .xsd = org/springframework/beans/factory/xml/spring-util- 2.0 .xsd
http\://www.springframework.org/schema/aop/spring-aop- 2.0 .xsd = org/springframework/aop/config/spring-aop- 2.0 .xsd
http\://www.springframework.org/schema/lang/spring-lang- 2.0 .xsd = org/springframework/scripting/config/spring-lang- 2.0 .xsd
http\://www.springframework.org/schema/tx/spring-tx- 2.0 .xsd = org/springframework/transaction/config/spring-tx- 2.0 .xsd
http\://www.springframework.org/schema/jee/spring-jee- 2.0 .xsd = org/springframework/ejb/config/spring-jee- 2.0 .xsd
http\://www.springframework.org/schema/beans/spring-beans.xsd = org/springframework/beans/factory/xml/spring-beans- 2.0 .xsd
http\://www.springframework.org/schema/tool/spring-tool.xsd = org/springframework/beans/factory/xml/spring-tool- 2.0 .xsd
http\://www.springframework.org/schema/util/spring-util.xsd = org/springframework/beans/factory/xml/spring-util- 2.0 .xsd
http\://www.springframework.org/schema/aop/spring-aop.xsd = org/springframework/aop/config/spring-aop- 2.0 .xsd
http\://www.springframework.org/schema/lang/spring-lang.xsd = org/springframework/scripting/config/spring-lang- 2.0 .xsd
http\://www.springframework.org/schema/tx/spring-tx.xsd = org/springframework/transaction/config/spring-tx- 2.0 .xsd
http\://www.springframework.org/schema/jee/spring-jee.xsd = org/springframework/ejb/config/spring-jee- 2.0 .xsd
從以上的文件中,可以看出XML Sechema文件在類包中位置。
DWR 2.0 RC 2中的XML Schema文件
根據上面的描述,我打開DWR的jar包中spring.schemas文件,內容如下:
然后,按照上面的路徑打開spring-dwr-2.0.xsd文件,內容如下:
<!-- 省略了版權信息 -->
< xsd:schema xmlns ="http://www.directwebremoting.org/schema/spring-dwr"
? ? ? ? ? ? xmlns:xsd ="http://www.w3.org/2001/XMLSchema"
? ? ? ? ? ? targetNamespace ="http://www.directwebremoting.org/schema/spring-dwr"
? ? ? ? ? ? elementFormDefault ="qualified"
? ? ? ? ? ? attributeFormDefault ="unqualified" >
<!-- 省略了具體的定義 -->
</ xsd:schema >
文件spring-dwr-2.0.xsd告訴我們,其名稱空間應為“http://www.directwebremoting.org/schema/spring-dwr”,所以我們在配置Spring 2時,應使用以上的名稱空間,如下面的代碼片段所示:
< beans xmlns ="http://www.springframework.org/schema/beans"
? ? xmlns:dwr ="http://www.directwebremoting.org/schema/spring-dwr"
? ? xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
? ? xsi:schemaLocation ="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
? ? ? ?http://www.directwebremoting.org/schema/spring-dwr http://www.directwebremoting.org/schema/spring-dwr-2.0.xsd" >
? ? < dwr:configuration >
? ? ? ? < dwr:convert class ="net.blogjava.max.pws.domain.Album" type ="bean" >
? ? ? ? ? ? < dwr:exclude method ="photos" />
? ? ? ? </ dwr:convert >
? ? ? ? < dwr:convert class ="net.blogjava.max.pws.domain.Photo" type ="bean" >
? ? ? ? ? ? < dwr:exclude method ="original, poster, thumb, full, album" />
? ? ? ? </ dwr:convert >
? ? </ dwr:configuration >
? ? < bean id ="ajaxFacade"
? ? ? ? class ="net.blogjava.max.pws.web.ajax.AjaxFacade" >
? ? ? ? < dwr:remote javascript ="AjaxFacade" />
? ? ? ? < property name ="personalWebSite" ref ="personalWebSite" />
? ? </ bean >
</ beans >
WEB-INF/web.xml配置
通過上面的配置,我們可以省去dwr.xml配置,不過在web.xml配置dwr的Servlet時,要使用新的Servlet類。配置代碼片段如下:
? ? < servlet-name > dwr </ servlet-name >
? ? < servlet-class > org.directwebremoting.spring.DwrSpringServlet </ servlet-class >
? ? < init-param >
? ? ? ? < param-name > debug </ param-name >
? ? ? ? < param-value > true </ param-value >
? ? </ init-param >
? ? < load-on-startup > 1 </ load-on-startup >
</ servlet >
< servlet-mapping >
? ? < servlet-name > dwr </ servlet-name >
? ? < url-pattern > /dwr/* </ url-pattern >
</ servlet-mapping >
總結
通過在Spring 2整合DWR 2配置,可以集中管理應用程序的配置,從一定程度上解決JavaEE開發中的配置文件泛濫的問題。