Java Portable for Windows

The description of Java Portable - Play With New Friends

Take Java Wherever It's Needed, Without Pesky Restrictions.Java Portable is an applet that lets you run Java on many computer systems that don't have it preinstalled. It often works even without admin rights, and it can be bundled along with the portable apps it's intended to work with. It doesn't work as well with non-portable software, though, and it's slower than standard Java.