How To Deploy Custom JAR files for Oracle iStore R12
Preface
Recently I’ve been working on a project to customize Oracle iStore R12, and I encountered a little problem when including custom jar files in my code. But it’s very odd that many people on the Internet have already got this problem while nobody can offer a solution. So I created a SR and finally got the answer from Oracle.
Body
Oracle has a document talking about my issue in 11i, whose document id is 468181.1. But I found the architecture of iStore changed so greatly from 11i to R12 that the document is obsolete now. Because that document asks me to edit $IAS_ORACLE_HOME/Apache/Jserv/etc/jserv.properties, but this file doesn’t even exist in R12.
So, the way to include a custom jar lib is to edit $ORA_CONFIG_HOME/10.1.3/j2ee/oacore/application-deployments/oacore/orion-application.xml, which is the correct configuration file for iStore R12. And we should add entries like this: <library path=”/<your directory>/customstore.jar” />. Then bounce the oacore and enjoy 
PS: If you are viewing the document 468181.1 in metalink now, you should find the steps I said above, and the title is “R12/11: How To Deploy Custom JSP and JAR files for Oracle iStore?”. But before I raised my SR, the title of this document is “11i: How To Deploy Custom JSP and JAR files for Oracle iStore?”, and there is no R12 contents, so it’s obivous that Oracle modify the article after my SR. Funny.