2017-10-31 04:04:13,858 ERROR [sitemap.handled-errors] (http-nio-8080-exec-1;/fr/index.html) Sitemap: error when calling sub-sitemap
        at <map:mount> - resource://org/ametys/runtime/kernel/sitemap.xmap:182:109
org.apache.cocoon.ProcessingException: Sitemap: error when calling sub-sitemap
        at <map:mount> - resource://org/ametys/runtime/kernel/sitemap.xmap:182:109
        at org.apache.cocoon.ProcessingException.throwLocated(ProcessingException.java:113)
        at org.apache.cocoon.components.treeprocessor.sitemap.MountNode.invoke(MountNode.java:122)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
        at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
        at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
        at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
        at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
        at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:178)
        at org.apache.cocoon.components.treeprocessor.TreeProcessor.process(TreeProcessor.java:254)
        at org.apache.cocoon.Cocoon.process(Cocoon.java:699)
        at org.ametys.runtime.servlet.RuntimeServlet.service(RuntimeServlet.java:543)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
        at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783)
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:789)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1437)
        at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
        at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
        at org.ametys.site.GeneratePageAction._writePageOnDisk(GeneratePageAction.java:324)
        at org.ametys.site.GeneratePageAction.act(GeneratePageAction.java:131)
        at org.apache.cocoon.components.treeprocessor.sitemap.ActTypeNode.invoke(ActTypeNode.java:120)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
        at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
        at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
        at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
        at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
        at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.handleCocoonRedirect(ConcreteTreeProcessor.java:300)
        at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.access$000(ConcreteTreeProcessor.java:49)
        at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor$TreeProcessorRedirector.cocoonRedirect(ConcreteTreeProcessor.java:348)
        at org.apache.cocoon.environment.ForwardRedirector.redirect(ForwardRedirector.java:60)
        at org.apache.cocoon.components.treeprocessor.sitemap.RedirectToURINode.invoke(RedirectToURINode.java:70)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
        at org.apache.cocoon.components.treeprocessor.sitemap.ActTypeNode.invoke(ActTypeNode.java:139)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
        at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
        at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
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