Xwiki 10.8 initialization failed [solved]

I just updated my wiki to 10.8 from 10.6 and I get the following error when I try to access the wiki:

XWiki initialization failed!

Storage schema updates and data migrations are enabled
No data migration to apply for wiki [xwiki] currently in version [1004001]
Checking Hibernate mapping and updating schema if needed for wiki [xwiki]
No data migration to apply for wiki [archive] currently in version [1004001]
Checking Hibernate mapping and updating schema if needed for wiki [archive]
No data migration to apply for wiki [it] currently in version [1004001]
Checking Hibernate mapping and updating schema if needed for wiki [it]
com.xpn.xwiki.objects.classes.BaseClass.addBooleanField(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/Boolean;)Z
class java.lang.NoSuchMethodError: com.xpn.xwiki.objects.classes.BaseClass.addBooleanField(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/Boolean;)Z
    at org.xwiki.wiki.template.internal.WikiTemplateClassDocumentInitializer.createClass(WikiTemplateClassDocumentInitializer.java:104)
    at com.xpn.xwiki.doc.AbstractMandatoryClassInitializer.updateDocument(AbstractMandatoryClassInitializer.java:75)
    at com.xpn.xwiki.XWiki.initializeMandatoryDocument(XWiki.java:1293)
    at com.xpn.xwiki.XWiki.initializeMandatoryDocuments(XWiki.java:1265)
    at com.xpn.xwiki.XWiki.initXWiki(XWiki.java:1204)
    at com.xpn.xwiki.XWiki.initXWiki(XWiki.java:1118)
    at com.xpn.xwiki.XWiki.<init>(XWiki.java:1091)
    at com.xpn.xwiki.internal.XWikiInitializerJob.runInternal(XWikiInitializerJob.java:117)
    at org.xwiki.job.AbstractJob.runInContext(AbstractJob.java:206)
    at org.xwiki.job.AbstractJob.run(AbstractJob.java:189)
    at java.lang.Thread.run(Thread.java:748)

Does anyone have any idea how I can debug and solve this problem?

Thanks.

Hi @pdwalker

It seems like a problem when you upgraded the WAR since this seems to indicate the oldcore JAR in WEB-INF/lib is not the correct one. Could you check?

EDIT: either the xwiki-*-oldcore.jar JAR or some xwiki-*-wiki-*.jar one

-rw-r–r-- 1 root root 3225434 Apr 11 21:32 xwiki-platform-legacy-oldcore-10.2.1-20180411.133229-7.jar
-rw-r–r-- 1 root root 4896032 Sep 25 00:17 xwiki-platform-legacy-oldcore-10.8.jar

Hmm… I think that may be it. Let me remove the 10.2.1.* version and try again.

And that seems to have solved the problem.

The weird versioned jar file was one given to me (by you, I believe) as a quick fix to an earlier memory leak problem, which I had then forgotten about.

Well spotted, and thanks for the fast help.