【发布时间】：2015-05-18 23:43:24
【问题描述】：
我在将 RF 3.3.3 DataTable 迁移到 RF 4.3.3-Final 时遇到问题，我正在使用 rich:dataScroller 进行服务器端分页，其中 scrollListener 属性触发 backingbean 方法以获取下一批结果。
到目前为止，我已经更新了 rich:dataScroller 和 scrollListener 名称以匹配 RF4 规范
<rich:dataScroller page="#{viewSignatures.signaturesTable.currentPage}"
scrollListener="#{viewSignatures.actionOnPageChange}" maxPages="5"
fastControls="show" stepControls="hide" renderIfSinglePage="false">
</rich:dataScroller>
然后在操作方法上我添加了 DataScrollEvent 参数（但不确定这是否必要？）
@Override
public void actionOnPageChange(DataScrollEvent event) {
String val = event.getNewScrolVal();
log.info(val);
return val;
}
当我更改页面时，出现以下异常：
17:32:59,158 ERROR [org.jboss.seam.exception.Exceptions] (ajp-localhost/127.0.0.1:8009-9) handled and logged exception: javax.servlet.ServletException
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:606) [jboss-jsf-api_2.1_spec-2.1.18.Final.jar:2.1.18.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:295) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:60) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:73) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158) [jboss-seam.jar:2.3.1.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:149) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.modcluster.container.jbossweb.JBossWebContext$RequestListenerValve.event(JBossWebContext.java:67)
at org.jboss.modcluster.container.jbossweb.JBossWebContext$RequestListenerValve.invoke(JBossWebContext.java:48)
at org.jboss.as.web.session.ClusteredSessionValve.handleRequest(ClusteredSessionValve.java:134) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.web.session.ClusteredSessionValve.invoke(ClusteredSessionValve.java:99) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.web.session.JvmRouteValve.invoke(JvmRouteValve.java:92) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.web.session.LockingValve.invoke(LockingValve.java:64) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:169) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:145) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:97) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:102) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:336) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:488) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.coyote.ajp.AjpProtocol$AjpConnectionHandler.process(AjpProtocol.java:420) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:920) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at java.lang.Thread.run(Thread.java:695) [classes.jar:1.6.0_65]
Caused by: java.lang.NullPointerException
at org.richfaces.taglib.MethodExpressionScrollListener.processDataScroll(MethodExpressionScrollListener.java:27) [richfaces-components-ui-4.3.3.Final.jar:4.3.3.Final]
at org.richfaces.event.DataScrollEvent.processListener(DataScrollEvent.java:83) [richfaces-components-api-4.3.3.Final.jar:4.3.3.Final]
at javax.faces.component.UIComponentBase.broadcast(UIComponentBase.java:775) [jboss-jsf-api_2.1_spec-2.1.18.Final.jar:2.1.18.Final]
at org.richfaces.component.AbstractDataScroller.broadcast(AbstractDataScroller.java:206) [richfaces-components-ui-4.3.3.Final.jar:4.3.3.Final]
at org.richfaces.component.RowKeyContextEventWrapper.broadcast(RowKeyContextEventWrapper.java:104) [richfaces-components-ui-4.3.3.Final.jar:4.3.3.Final]
at org.richfaces.component.UIDataAdaptor.broadcast(UIDataAdaptor.java:448) [richfaces-components-ui-4.3.3.Final.jar:4.3.3.Final]
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:786) [jboss-jsf-api_2.1_spec-2.1.18.Final.jar:2.1.18.Final]
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1251) [jboss-jsf-api_2.1_spec-2.1.18.Final.jar:2.1.18.Final]
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81) [jsf-impl-2.1.18-jbossorg-1.jar:]
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.18-jbossorg-1.jar:]
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.18-jbossorg-1.jar:]
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jboss-jsf-api_2.1_spec-2.1.18.Final.jar:2.1.18.Final]
... 32 more
17:32:59,207 ERROR [org.jboss.seam.exception.Exceptions] (ajp-localhost/127.0.0.1:8009-9) handled and logged exception: java.lang.NullPointerException: Argument Error: Parameter message is null
at com.sun.faces.util.Util.notNull(Util.java:299) [jsf-impl-2.1.18-jbossorg-1.jar:]
at com.sun.faces.context.FacesContextImpl.addMessage(FacesContextImpl.java:492) [jsf-impl-2.1.18-jbossorg-1.jar:]
at org.jboss.seam.faces.FacesMessages.beforeRenderResponse(FacesMessages.java:45) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.jsf.SeamPhaseListener.beforeRenderResponse(SeamPhaseListener.java:488) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.jsf.SeamPhaseListener.beforeServletPhase(SeamPhaseListener.java:147) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.jsf.SeamPhaseListener.beforePhase(SeamPhaseListener.java:117) [jboss-seam.jar:2.3.1.Final]
at com.sun.faces.lifecycle.Phase.handleBeforePhase(Phase.java:228) [jsf-impl-2.1.18-jbossorg-1.jar:]
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:99) [jsf-impl-2.1.18-jbossorg-1.jar:]
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139) [jsf-impl-2.1.18-jbossorg-1.jar:]
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594) [jboss-jsf-api_2.1_spec-2.1.18.Final.jar:2.1.18.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:295) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:60) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:73) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.1.Final]
at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158) [jboss-seam.jar:2.3.1.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:149) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.modcluster.container.jbossweb.JBossWebContext$RequestListenerValve.event(JBossWebContext.java:67)
at org.jboss.modcluster.container.jbossweb.JBossWebContext$RequestListenerValve.invoke(JBossWebContext.java:48)
at org.jboss.as.web.session.ClusteredSessionValve.handleRequest(ClusteredSessionValve.java:134) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.web.session.ClusteredSessionValve.invoke(ClusteredSessionValve.java:99) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.web.session.JvmRouteValve.invoke(JvmRouteValve.java:92) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.web.session.LockingValve.invoke(LockingValve.java:64) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.2.0.Final.jar:7.2.0.Final]
at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:169) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:145) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:97) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:102) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:336) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:488) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.coyote.ajp.AjpProtocol$AjpConnectionHandler.process(AjpProtocol.java:420) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:920) [jbossweb-7.2.0.Final.jar:7.2.0.Final]
at java.lang.Thread.run(Thread.java:695) [classes.jar:1.6.0_65]
“NullPointerException: Argument Error: Parameter message is null”部分异常会重复 20-30 次，从而导致重定向循环
【问题讨论】：
-
看起来像一个射频错误；在此处发布完整的堆栈跟踪
-
@kolossus 确定添加
-
基于RichFaces源码，NPE是因为
MethodExpression是null。经过进一步检查，scrollListener似乎需要一个void方法。但是，您有一个返回String的方法（这仅适用于返回导航结果的操作方法，而不适用于侦听器方法）。尝试将其设为void方法，并让我知道这是否确实解决了问题。 -
@BalusC 好地方！不幸的是，尽管在将方法更改为 void 后，它仍然会引发相同的异常（有或没有 DataScrollEvent arg）
-
另一个可能的原因是
FacesContext#getCurrentInstance()在那里返回了null。但这将是一个相当严重的问题，其后果应该不止于此。您是否能够在此处放置调试断点，以便检查两者中的哪一个是null？FacesContext或MethodExpression？无论如何，您是否有机会将 JBoss AS 捆绑的 Mojarra 2.1.18 升级到更新的版本？目前已经是 2.1.29。您可以在此答案中找到 JBoss AS 升级说明：stackoverflow.com/a/17085879 或者试试 WildFly 8.2。