java.util.ConcurrentModificationException

There are no available Samebug tips for this exception. Do you have an idea how to solve this issue? A short tip would help users who saw this issue last week.

  • Any attempt to make duplication entry gives an error described below. No correct duplication check is done. How to reproduce: - make any application - make an entry - try to make another entry with the same name. - follow the error code: Error number 0 in 11: Uncaught exception Wrapped Exception: null com.xpn.xwiki.XWikiException: Error number 0 in 11: Uncaught exception Wrapped Exception: null at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:252) at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:116) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) at javax.servlet.http.HttpServlet.service(HttpServlet.java:820) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:538) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1352) at com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:128) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:144) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:68) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:217) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:109) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:476) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:119) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:517) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:225) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:937) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:406) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:183) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:871) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:247) at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:149) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110) at org.eclipse.jetty.server.Server.handle(Server.java:346) at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:589) at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:1048) at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:601) at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:214) at org.eclipse.jetty.server.HttpConnection.handle(HttpConnection.java:411) at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:535) at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:40) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529) at java.lang.Thread.run(Unknown Source) Wrapped Exception: java.util.ConcurrentModificationException at java.util.AbstractList$Itr.checkForComodification(Unknown Source) at java.util.AbstractList$Itr.next(Unknown Source) at com.xpn.xwiki.doc.XWikiDocument.setXObjects(XWikiDocument.java:2089) at com.xpn.xwiki.doc.XWikiDocument.mergeXObjects(XWikiDocument.java:2437) at com.xpn.xwiki.doc.XWikiDocument.readFromTemplate(XWikiDocument.java:3271) at com.xpn.xwiki.doc.XWikiDocument.readFromTemplate(XWikiDocument.java:3289) at com.xpn.xwiki.doc.XWikiDocument.readFromTemplate(XWikiDocument.java:3224) at com.xpn.xwiki.web.EditAction.render(EditAction.java:117) at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:229) at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:116) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) at javax.servlet.http.HttpServlet.service(HttpServlet.java:820) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:538) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1352) at com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:128) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:144) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:68) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:217) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:109) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:476) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:119) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:517) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:225) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:937) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:406) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:183) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:871) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:247) at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:149) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110) at org.eclipse.jetty.server.Server.handle(Server.java:346) at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:589) at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:1048) at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:601) at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:214) at org.eclipse.jetty.server.HttpConnection.handle(HttpConnection.java:411) at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:535) at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:40) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529) at java.lang.Thread.run(Unknown Source)
    via by Dmitry Bakbardin,
  • ConcurrentModificationException over list
    via Stack Overflow by Rob Fox
    ,
  • Removing elements from an ArrayList
    via Stack Overflow by Alberto Does
    ,
    • java.util.ConcurrentModificationException at java.util.AbstractList$Itr.checkForComodification(Unknown Source) at java.util.AbstractList$Itr.next(Unknown Source) at com.xpn.xwiki.doc.XWikiDocument.setXObjects(XWikiDocument.java:2089) at com.xpn.xwiki.doc.XWikiDocument.mergeXObjects(XWikiDocument.java:2437) at com.xpn.xwiki.doc.XWikiDocument.readFromTemplate(XWikiDocument.java:3271) at com.xpn.xwiki.doc.XWikiDocument.readFromTemplate(XWikiDocument.java:3289) at com.xpn.xwiki.doc.XWikiDocument.readFromTemplate(XWikiDocument.java:3224) at com.xpn.xwiki.web.EditAction.render(EditAction.java:117) at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:229) at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:116) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) at javax.servlet.http.HttpServlet.service(HttpServlet.java:820) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:538) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1352) at com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:128) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:144) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:68) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:217) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:109) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:476) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:119) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:517) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:225) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:937) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:406) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:183) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:871) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:247) at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:149) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110) at org.eclipse.jetty.server.Server.handle(Server.java:346) at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:589) at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:1048) at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:601) at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:214) at org.eclipse.jetty.server.HttpConnection.handle(HttpConnection.java:411) at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:535) at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:40) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529) at java.lang.Thread.run(Unknown Source)

    Users with the same issue

    Unknown visitor
    Unknown visitor1 times, last one,
    Unknown visitor
    Unknown visitor1 times, last one,
    Unknown visitor
    Unknown visitor1 times, last one,
    Unknown visitor
    Unknown visitor1 times, last one,
    PilleoPilleo
    4 times, last one,