Your stack trace seems to indicate that conduit (a mechanism connecting Tapestry with a column) is not available. It can happen if the column is manually added to the model. Was the column sortable with Tapestry 5.3.7? How is this column defined?
Best regards, Cezary On Mon, Jun 27, 2016 at 4:43 PM, Davide Vecchi <d...@amc.dk> wrote: > Hi everybody > > For now I cannot post code to reproduce this problem because it only > occurs with one columns of a specific grid from a big application and so > far I wasn't able to extract the code to reproduce the error into a > runnable example. But after posting this I will keep trying and if I manage > I will post that. > > We migrated this web application from Java 1.7 + Tapestry 5.3.7 to Java > 1.8 with Tapestry 5.3.8 . > > Clicking on the column header of this column - which contains String > values - causes the exception below. > > While I'm investigating this error I was wondering if someone is aware of > differences in the grid sorting of Tapestry 5.3.8 that might cause it to > throw a null-pointer where Tapestry 5.3.7 wouldn't (and maybe should; it's > likely that there is a mistake of mine that was somehow being "forgiven" by > 5.3.7). > > Stacktrace: > > java.lang.NullPointerException > ? > org.apache.tapestry5.internal.grid.CollectionGridDataSource$2.compare(CollectionGridDataSource.java:78) > ? > org.apache.tapestry5.internal.grid.CollectionGridDataSource$3.compare(CollectionGridDataSource.java:91) > ? java.util.TimSort.countRunAndMakeAscending(TimSort.java:355) > ? java.util.TimSort.sort(TimSort.java:234) > ? java.util.Arrays.sort(Arrays.java:1512) > ? java.util.ArrayList.sort(ArrayList.java:1454) > ? java.util.Collections.sort(Collections.java:175) > ? > org.apache.tapestry5.internal.grid.CollectionGridDataSource.prepare(CollectionGridDataSource.java:97) > ? > my.package.gui.tapestry.components.AMCGridEmbedded$CachingDataSource.prepare(AMCGridEmbedded.java:853) > ? > my.package.gui.tapestry.components.AMCGridEmbedded.setupDataSource(AMCGridEmbedded.java:1174) > ? > my.package.gui.tapestry.components.AMCGridEmbedded.setupRender(AMCGridEmbedded.java:655) > ? > my.package.gui.tapestry.components.AMCGridEmbedded.advised$setupRender_1a14d3f8fd924(AMCGridEmbedded.java) > ? > my.package.gui.tapestry.components.AMCGridEmbedded$Invocation_setupRender_1a14d3f8fd923.proceedToAdvisedMethod(Unknown > Source) > ? > org.apache.tapestry5.internal.plastic.AbstractMethodInvocation.proceed(AbstractMethodInvocation.java:84) > ? .... > ? .... > >
