Datahub change new version of a JAR in lib folder

Hi Experts, If i wanted to change the version of validation-api-1.0.0.GA in ../TOMCAT../datahub-webapp/.../lib folder to newer version what are the steps required? When a newer version is replaced it doesn't take effect or its not loaded by the class loader.

Pl me know how to replace a JAR with new version.

Hybris - 6.3.0.0

Thanks, Srini