文章地址:http://www.ibm.com/developerworks/cn/java/j-jettydwr/
一些問題:
1、web.xml配配置,DWR使用2.0RC3以下版本時(shí)須全用選項(xiàng):pollAndCometEnabled代替activeReverseAjaxEnabled,如下:
<servlet>
<servlet-name>dwr-invoker</servlet-name>
<servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
<!-- 2.0 RC3以上版本使用.
<init-param>
<param-name>activeReverseAjaxEnabled</param-name>
<param-value>true</param-value>
</init-param>
-->
<init-param>
<param-name>pollAndCometEnabled</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>initApplicationScopeCreatorsAtStartup</param-name>
<param-value>true</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>dwr-invoker</servlet-name>
<url-pattern>/dwr/*</url-pattern>
</servlet-mapping>
<servlet-name>dwr-invoker</servlet-name>
<servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
<!-- 2.0 RC3以上版本使用.
<init-param>
<param-name>activeReverseAjaxEnabled</param-name>
<param-value>true</param-value>
</init-param>
-->
<init-param>
<param-name>pollAndCometEnabled</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>initApplicationScopeCreatorsAtStartup</param-name>
<param-value>true</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>dwr-invoker</servlet-name>
<url-pattern>/dwr/*</url-pattern>
</servlet-mapping>
選項(xiàng)說明(http://getahead.org/dwr/server/servlet 可查詢更多參數(shù)的說明):
1)、activeReverseAjaxEnabled
true 表示激活輪詢和 Comet 功能。2.0 RC3以前版本,參數(shù)名為:pollAndCometEnabled。
2)、initApplicationScopeCreatorsAtStartup 通知 DWR 在應(yīng)用程序啟動(dòng)時(shí)初始化
ReverseAjaxTracker
。這將在對(duì) bean 生成第一個(gè)請(qǐng)求時(shí)改寫延遲初始化(lazy initialization)的常規(guī)行為 —— 在本例中這是必須的,因?yàn)榭蛻魴C(jī)不會(huì)主動(dòng)對(duì) ReverseAjaxTracker
調(diào)用方法。