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Grails Runtime Exception

Error 500: Internal Server Error

URI
/category/food/potatoes-and-tubers
Class
java.util.ConcurrentModificationException
Message
null

Trace

    Line | Method
->>  922 | nextEntry             in java.util.HashMap$HashIterator
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
|    962 | next                  in java.util.HashMap$EntryIterator
|    960 | next . . . . . . . .  in     ''
|     98 | $tt__retrieveArticles in org.commenthow.ArticleService
|    184 | doCall . . . . . . .  in GrailsMelodyGrailsPlugin$_closure4_closure16_closure17
|   1629 | galleryImpl           in org.commenthow.ArticleController
|   1592 | gallery . . . . . . . in     ''
|    198 | doFilter              in grails.plugin.cache.web.filter.PageFragmentCachingFilter
|     63 | doFilter . . . . . .  in grails.plugin.cache.web.filter.AbstractFilter
|    203 | run                   in gsp_commentHowindex_gsp
|    198 | doFilter . . . . . .  in net.bull.javamelody.MonitoringFilter
|    176 | doFilter              in     ''
|     53 | doFilter . . . . . .  in grails.plugin.springsecurity.web.filter.GrailsAnonymousAuthenticationFilter
|     49 | doFilter              in grails.plugin.springsecurity.web.authentication.RequestHolderAuthenticationFilter
|     82 | doFilter . . . . . .  in grails.plugin.springsecurity.web.authentication.logout.MutableLogoutFilter
|     41 | invoke                in com.googlecode.psiprobe.Tomcat80AgentValve
|   1145 | runWorker . . . . . . in java.util.concurrent.ThreadPoolExecutor
|    615 | run                   in java.util.concurrent.ThreadPoolExecutor$Worker
^    745 | run . . . . . . . . . in java.lang.Thread