This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
I'd think that it is named 'appletviewer' in Linux as well. It might not be in your PATH, though - check the various directories containing binaries if something got installed there. It's probably in the same directory as 'javac'.