WebLogic is still bundled with JDK6 yet changing to JDK7 is a piece of cake.
- Install JDK7u2 or later
- Update the setDomainEnv.sh script of your domain for the new JDK
- Restart your domain
You can follow the steps in the video below and also see the new jcmd tool in action. jcmd unifies the command-line tools (jhat, jstack, etc.) from previous versions.