Executing a program from within Java?

[Energize]

How do I execute an external program, eg the command line from within a java program?

 

[Fourstar]

I was about to say exec but searching for a tutorial I see java 5 introduced the ProcessBuilder.

Here is an article demonstrating both:
http://www.java-tips.org/java-se-tips/java.util/from-runtime.exec-to-processbuilder.html