I really do not think it matters too much these days if a Java Update is installed. Keep in mind that we distribute each version of DocuWare with a specific version of the JRE. Running Solr on a different version may lead to problems with Fulltext. So, regardless that updates have to be installed, if there is any mis-behavior from fulltext use Tim's guide above to reset Solr back to the JRE that was shipped with the version of DocuWare installed - OR - if it is running the released version then set it to the new one.
Recently I observed a 6.12 Solr running an updated JRE when I was troubleshooting other fulltext issues. So I set it back to the released version. In retrospect, it was not the root of the problem so I could have left it running the update. Not an exact science.
Senior Director Support Americas