关于tiles标签空指针的问题

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关于tiles标签空指针的问题0

问题描述：
框架spring mvc ，前台页面中使用了tiles标签，使用用户直接登录本系统没有问题，但是使用单点登录进入相应的页面，则会报错：nullpointer,错误信息如下：如果把页面的<t:insertAttribute name="left" />标签去掉，则不会报这个错，

严重: Servlet.service() for servlet mvc threw exception
java.lang.NullPointerException
	at org.apache.jsp.WEB_002dINF.views.index.road.road_005fleft_jsp._jspService(road_005fleft_jsp.java:67)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
	at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:551)
	at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:488)
	at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:968)
	at org.apache.jasper.runtime.PageContextImpl.doInclude(PageContextImpl.java:656)
	at org.apache.jasper.runtime.PageContextImpl.include(PageContextImpl.java:650)
	at org.apache.tiles.jsp.context.JspTilesRequestContext.include(JspTilesRequestContext.java:103)
	at org.apache.tiles.jsp.context.JspTilesRequestContext.dispatch(JspTilesRequestContext.java:96)
	at org.apache.tiles.renderer.impl.TemplateAttributeRenderer.write(TemplateAttributeRenderer.java:44)
	at org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
	at org.apache.tiles.renderer.impl.ChainedDelegateAttributeRenderer.write(ChainedDelegateAttributeRenderer.java:76)
	at org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
	at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:670)
	at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:336)
	at org.apache.tiles.template.InsertAttributeModel.renderAttribute(InsertAttributeModel.java:210)
	at org.apache.tiles.template.InsertAttributeModel.end(InsertAttributeModel.java:126)
	at org.apache.tiles.jsp.taglib.InsertAttributeTag.doTag(InsertAttributeTag.java:311)
	at org.apache.jsp.WEB_002dINF.views.template.home_jsp._jspx_meth_t_005finsertAttribute_005f0(home_jsp.java:298)
	at org.apache.jsp.WEB_002dINF.views.template.home_jsp._jspService(home_jsp.java:251)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
	at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436)
	at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374)
	at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302)
	at org.apache.tiles.servlet.context.ServletTilesRequestContext.forward(ServletTilesRequestContext.java:241)
	at org.apache.tiles.servlet.context.ServletTilesRequestContext.dispatch(ServletTilesRequestContext.java:222)
	at org.apache.tiles.renderer.impl.TemplateAttributeRenderer.write(TemplateAttributeRenderer.java:44)
	at org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
	at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:670)
	at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:690)
	at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:644)
	at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:627)
	at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:321)
	at org.springframework.web.servlet.view.tiles2.TilesView.renderMergedOutputModel(TilesView.java:124)
	at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:250)
	at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1047)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:817)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:669)
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:574)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.springframework.web.filter.ShallowEtagHeaderFilter.doFilterInternal(ShallowEtagHeaderFilter.java:58)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:48

请帮忙分析原因；
我的解决过程：
1：因为本地直接登录没事，单点跳转有事，怀疑是和跳转有关系，所以让单点登录成功后，跳转到一个静态页面，然后在静态页面点链接到相应的页面，这种解决办法失败；
2：在解决问题的过程中，发现一个问题，就是先在我们系统登录，成功之后，再次用单点登录登录到相应的页面，问题没有复现；（把cookies 历史记录删除，直接单点登录问题复现）
3：网上有人说jar包冲突，但是把lib 下面的个人认为冲突的jar 删掉，问题复现（有可能是我发现的冲突jar包不对，望指点）；
4：tiles使用的是2.0版本，

<bean id="tilesViewResolver"
		class="org.springframework.web.servlet.view.tiles2.TilesViewResolver" />
	<bean class="org.springframework.web.servlet.view.tiles2.TilesConfigurer">
		<property name="definitions">
			<list>
				<value>/WEB-INF/views/**/views.xml</value>
			</list>
		</property>
	</bean>

spring 使用的是3.0版本（spring 相应的jar 包中，是2.0的tiles类）
该问题已经困扰1天，一直没有找到解决办法，望知情人士解答。