Basic Customization > Windchill Customization Basics > Managing Customizations > Best Practices for Customizing Files Supplied by PTC > Managing Client JAR Files > Using the Client JAR Architecture > Updating Client JARs for Customizations
  
Updating Client JARs for Customizations
The Customization JAR components exist to allow customization additions and overrides to the out-of-the-box JAR sets as these components take load precedence over the corresponding DSU and FCS components.
A customer or customizer can add entries to any Customization .includes files they want and rebuild the corresponding JAR via:
ant -f MakeJar.xml buildCustClientJars
-DlogicalJarNames=jar1,jar2,…
where “jar1,jar2,…” should be replaced by the list of logical JARs whose Customization components should be rebuilt.
More often, however, the customer is likely to have a number of files they have overridden and simply wish to have the client JARs updated to account for this. This can be done by listing the overridden/customized files in codebase/jarContents/Cust.bom and then executing the command:
ant -f MakeJar.xml custUpdate
This command executes the following targets:
updateCustIncludes: Intersects each FCS .includes and DSU .includes file pair with jarContents/Cust.bom and adds the intersection to the corresponding Customization .includes file. Note that Cust.bom contains a few of the most volatile entries (e.g. properties files regenerated during code generation) initially out-of-the-box.
expandJarLocales: For resource bundles represented by _en localization in DSU and FCS .includes, places other localizations requested in jarContents/clientJarLocales into Customization .includes
buildCustClientJars: Re-builds all Customization JAR components. Also, builds all indexed head JARs which are parents (directly or indirectly) of these JARs.
Additionally more extensive client customizations can be supported by proceeding to build new client JAR sets in much the same way as was described for the previous sections.