I've experienced the exact same problem. You'll get this a lot when working with ajax components. I've also reported this issue to the wicket 2 jira. If you add if(versionManger != null) prior to the versionManager call you'll be fine but that's probably an ugly hack. But it seem to work til they've actually fixed it.
Aaron Hiniker-2 wrote: > > I pulled the latest from trunk. And I am getting this NPE: > > 16:30:14,543 ERROR [STDERR] java.lang.NullPointerException > 16:30:14,544 ERROR [STDERR] at > wicket.Page.componentStateChanging(Page.java:327) > 16:30:14,545 ERROR [STDERR] at > wicket.Component.addStateChange(Component.java:2553) > 16:30:14,545 ERROR [STDERR] at > wicket.Component.setModel(Component.java:2191) > 16:30:14,545 ERROR [STDERR] at > wicket.MarkupContainer.setModel(MarkupContainer.java:596) > 16:30:14,546 ERROR [STDERR] at > com.edicorp.erp.web.components.search.ProductSearchPanel.query(ProductSearchPanel.java:144) > 16:30:14,546 ERROR [STDERR] at > com.edicorp.erp.web.components.search.ProductSearchPanel.onUpdate(ProductSearchPanel.java:109) > 16:30:14,546 ERROR [STDERR] at > com.edicorp.erp.web.components.search.FilterPanel.fireOnChange(FilterPanel.java:74) > 16:30:14,547 ERROR [STDERR] at > com.edicorp.erp.web.components.search.query.QueryPanel$QueryForm.onSubmit(QueryPanel.java:197) > 16:30:14,547 ERROR [STDERR] at > wicket.markup.html.form.Form.delegateSubmit(Form.java:680) > 16:30:14,547 ERROR [STDERR] at > wicket.markup.html.form.Form.onFormSubmitted(Form.java:396) > 16:30:14,547 ERROR [STDERR] at > sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) > > > I remember I was getting this NPE before, and I patched the source to > include this null check in Page.java: > > final void componentStateChanging(final Component component, > Change change) > { > checkHierarchyChange(component); > > dirty(); > if (mayTrackChangesFor(component, null)) > { > if ( versionManager != null ) > > versionManager.componentStateChanging(change); > } > } > > It seems that everywhere else in Page.java there is a null check for > versionManager, except in this method. Not sure, but perhaps the > problem lies in the #mayTrackChangesFor() method, but in any case if I > add this null check my code runs fine. > > Aaron > > > ------------------------------------------------------------------------- > Take Surveys. Earn Cash. Influence the Future of IT > Join SourceForge.net's Techsay panel and you'll get the chance to share > your > opinions on IT & business topics through brief surveys-and earn cash > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > _______________________________________________ > Wicket-user mailing list > Wicket-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/wicket-user > > -- View this message in context: http://www.nabble.com/NPE-in-Page-componentStateChanging-tf3330773.html#a9347814 Sent from the Wicket - User mailing list archive at Nabble.com. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Wicket-user mailing list Wicket-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wicket-user