Error rendering the 404 URLs tab in the Redirection tool

Issue

• In a given site, a user navigates to Configuration > Redirection > 404 URLs (tab) and this error appears in the server logs:

  2022-02-22 13:26:42.295 ERROR [ajp-nio-0.0.0.0-8009-exec-50][IncludeTag:128] Current URL /group/revista-seguridad-social/~/control_panel/manage?p_p_id=com_liferay_redirect_web_internal_portlet_RedirectPortlet&p_p_lifecycle=0&p_p_state=maximized&p_p_mode=view&_com_liferay_redirect_web_internal_portlet_RedirectPortlet_navigation=404-urls generates exception: java.lang.NullPointerException
  java.lang.NullPointerException
  at com.liferay.redirect.web.internal.display.context.RedirectNotFoundEntriesManagementToolbarDisplayContext.getAvailableActions(RedirectNotFoundEntriesManagementToolbarDisplayContext.java:92)
  at org.apache.jsp.view_005fredirect_005fnot_005ffound_005fentries_jsp._jspService(view_005fredirect_005fnot_005ffound_005fentries_jsp.java:377)

Environment

• Liferay DXP 7.3+ 

Resolution

• This error could be produced because the index contains an element that was removed from the database. This inconsistency produces the error when logic tries to retrieve this object.
• As solution you could go to Control Panel > Search > Index Actions and execute the reindex actions for: 
  
  • Reindex com.liferay.redirect.model.RedirectEntry.
  • Reindex com.liferay.redirect.model.RedirectNotFoundEntry.
• Doing this, you'll regenerate and synchronize the database and your index.
• It's also convenient open a new ticket to support and ask them to check if you have the LPS-137405 in your installation. If you do not have it they could provide this fix to you.

Additional Information

• LPS-137405 StaleObjectStateException for RedirectNotFoundEntryImpl
• Using the Redirection tool