Use of "Utility Jars" folder in Websphere

Question

How can I add jars to the "Utility JARs" folder in websphere. If the required jar is already contained within the lib dir of a war which is contained in the ear, is the jar still required in the "Utility JARs" folder ?

Answer 1

Utility Jars typically contain classes that are used by multiple modules in an EAR. It does not make sense to keep multiple copies of those classes. For e.g. you have a Servlet and an EJB in an EAR using a shared Class. This shared class can be kept in a JAR (and placed as a utility Jar to the EAR).

Now it becomes available to both the servlet and EJB which are present in the EAR,

Utility jars are applicable to both a WAS based Java EE application and also a WPS based integration/bpel centric applications. I am guessing it is a WAS based Java EE application.

Refer to: http://www.ibm.com/developerworks/websphere/library/techarticles/0304_manji/manji.html

This is very old but the concept hasn't really changed all these years.

To specifically answer your question, if there is only WAR file in your EAR then there is no advantage of using the Utility JAR.

If you have multiple WARs in an EAR sharing classes, those shared classes are good candidates for a utility Jar

Hope this helps

Manglu