Si alguna vez tu servidor te ha arrojado el siguiente error:
ERROR [ColumnsHandler] FOREACH_BAD_ITEMS
javax.servlet.jsp.JspTagException: FOREACH_BAD_ITEMS
at org.richfaces.iterator.SimpleForEachIterator.toForEachIterator(SimpleForEachIterator.java:135)
at org.richfaces.iterator.SimpleForEachIterator.supportedTypeForEachIterator(SimpleForEachIterator.java:98)
at org.richfaces.taglib.ColumnsHandlerIterationContext.setValue(ColumnsHandlerIterationContext.java:233)
at org.richfaces.taglib.ColumnsHandler.prepare(ColumnsHandler.java:163)
at org.richfaces.taglib.ColumnsHandler.apply(ColumnsHandler.java:186)
at com.sun.facelets.tag.jsf.ComponentHandler.applyNextHandler(ComponentHandler.java:314)
at com.sun.facelets.tag.jsf.ComponentHandler.apply(ComponentHandler.java:169)
at com.sun.facelets.tag.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:47)
at com.sun.facelets.tag.jsf.ComponentHandler.applyNextHandler(ComponentHandler.java:314)
at com.sun.facelets.tag.jsf.ComponentHandler.apply(ComponentHandler.java:169)
at com.sun.facelets.tag.jsf.ComponentHandler.applyNextHandler(ComponentHandler.java:314)
at com.sun.facelets.tag.jsf.ComponentHandler.apply(ComponentHandler.java:169)
at com.sun.facelets.tag.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:47)
at com.sun.facelets.tag.jsf.ComponentHandler.applyNextHandler(ComponentHandler.java:314)
at com.sun.facelets.tag.jsf.ComponentHandler.apply(ComponentHandler.java:169)
at com.sun.facelets.tag.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:47)
at com.sun.facelets.tag.jsf.ComponentHandler.applyNextHandler(ComponentHandler.java:314)
at com.sun.facelets.tag.jsf.ComponentHandler.apply(ComponentHandler.java:169)
at com.sun.facelets.tag.ui.DefineHandler.applyDefinition(DefineHandler.java:64)
at com.sun.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:131)
at com.sun.facelets.impl.DefaultFaceletContext$TemplateManager.apply(DefaultFaceletContext.java:337)
at com.sun.facelets.impl.DefaultFaceletContext.includeDefinition(DefaultFaceletContext.java:307)
at com.sun.facelets.tag.ui.InsertHandler.apply(InsertHandler.java:68)
at com.sun.facelets.tag.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:47)
at com.sun.facelets.tag.jsf.core.ViewHandler.apply(ViewHandler.java:109)
at com.sun.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:49)
at com.sun.facelets.tag.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:47)
at com.sun.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:25)
at com.sun.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:248)
at com.sun.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:294)
at com.sun.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:273)
at com.sun.facelets.impl.DefaultFaceletContext.includeFacelet(DefaultFaceletContext.java:140)
at com.sun.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:113)
at com.sun.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:49)
at com.sun.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:25)
at com.sun.facelets.impl.DefaultFacelet.apply(DefaultFacelet.java:95)
at com.sun.facelets.FaceletViewHandler.buildView(FaceletViewHandler.java:524)
at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:567)
at org.ajax4jsf.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:100)
at org.ajax4jsf.application.AjaxViewHandler.renderView(AjaxViewHandler.java:176)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:109)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:100)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:266)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83)
at org.jboss.seam.web.IdentityFilter.doFilter(IdentityFilter.java:38)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:90)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:206)
at org.ajax4jsf.webapp.BaseFilter.handleRequest(BaseFilter.java:290)
at org.ajax4jsf.webapp.BaseFilter.processUploadsAndHandleRequest(BaseFilter.java:388)
at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:515)
at org.jboss.seam.web.Ajax4jsfFilter.doFilter(Ajax4jsfFilter.java:56)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:58)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.debug.hot.HotDeployFilter.doFilter(HotDeployFilter.java:44)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:182)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:432)
at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:262)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:446)
at java.lang.Thread.run(Thread.java:619)
Por lo general esta asociado a los tags: rich:columns y dataTable y no es un error que pueda ser manejado por bloques try y catch. Por ejemplo, en el siguiente código es muy frecuente:
< rich:datatable id="tblVistaPrevia" value="">
< rich:columns value="#{MiBackBean.columnasVistaPrevia}" var="columna">
< f:facet name="header">#{columna}
< /rich:columns>
< /rich:datatable>
< rich:columns value="#{MiBackBean.columnasVistaPrevia}" var="columna">
< f:facet name="header">#{columna}
< /rich:columns>
< /rich:datatable>
La raíz de este error radica en que el valor que se asocia al tag rich:columns es nulo. Al querer accesar al valor e iterarlo no puede manejar un valor nulo. Por lo tanto, es necesario inicializar la colección "columnasVistaPrevia". De esta manera el error desaparecerá.
