[原]Tomcat crossContext

[标题]:Tomcat crossContext
[时间]:2009-6-1
[摘要]:当<c:import >指定了context属性时，应该设置%TOMCAT_HOME%/conf/context.xml的Context中的属性crossContext="true"。
[关键字]:context、tag、crossContext、JSP、Servlet
[环境]:Tomcat 6、Window XP SP3
[作者]:Winty ([e-mail]) http://www.blogjava.net/wintys

[错误]:
    在使用<c:import url="/MyHtml.html" context=”/sample2” var="thisPage"/>时，使用context指定了同一服务器下的另一个WebApp的资源时(即访问WEB_ROOT/sample2/MyHtml.html)，出现如下错误提示:
javax.servlet.ServletException: javax.servlet.jsp.JspTagException: In URL tags, when the "context" attribute is specified, values of both "context" and "url" must start with "/".

[原因]:
    Tomcat默认不能跨WebApp进行访问。

[解决]:
    %TOMCAT_HOME%/conf/context.xml的Context中的属性crossContext="true"。

    完整的context.xml内容如下:

<!-- The contents of this file will be loaded for each web application -->
<Context crossContext="true">

    <!-- Default set of monitored resources -->
    <WatchedResource>WEB-INF/web.xml</WatchedResource>
    
    <!-- Uncomment this to disable session persistence across Tomcat restarts -->
    <!--
    <Manager pathname="" />
    -->

</Context>

    Tomcat文档中对crossContext的说明:Set to true if you want calls within this application to ServletContext.getContext() to successfully return a request dispatcher for other web applications running on this virtual host. Set to false (the default) in security conscious environments, to make getContext() always return null.

[参考资料]:
%TOMCAT_HOME%/webapps/docs/config/context.html