I use http://sourceforge.net/projects/jcsc/
Like it very much.
There are also some plugins for eclipse...

Hugo

Wenbo <wenboz@nortelnetworks.com> wrote or quoted:

See:

Checkstyle
http://checkstyle.sourceforge.net/

See also:

PMD                                            
http://pmd.sourceforge.net/

JCSC - Java Coding Standards Checker - GPL
http://jcsc.sourceforge.net/

JavaWizzard              
http://csdl.ics.hawaii.edu/Research/JWiz/JWiz.html

RevJava  
http://www.serc.nl/people/florijn/work/designchecking/RevJava.htm

Lint tools for Java        
http://pmd.sourceforge.net/similar-projects.html

TOAD                                
http://www.alphaworks.ibm.com/tech/toad

JiveLint                            
http://www.bysoft.se/sureshot/javalint/

JTest                              
http://www.parasoft.com/products/jtest/

JLint                                      
http://www.garret.ru/~knizhnik/

JLint - Windows
http://artho.com/jlint/manual.html

Code Companion - Lint for $s
http://www.jenssoft.com/

WaspSoft      
http://www.waspsoft.com/

Simian                
http://www.redhillconsulting.com.au/products/simian/

JQuery                      
http://www.cs.ubc.ca/labs/spl/projects/jquery/

QStudio for Java Pro</a> (QA systems)
http://www.qa-systems.com/welcome.html

Take a look at the download at http://hammurapi.org .

It makes certain you close you db connections in a finally clause,
Bulks at long files, overly complex methods, scolds you if you
don't use a logger, and does a bunch of useless but interesting
things such as check your import statements (alphabatical
with no asterisks).

You run hammurapi as an ANT task and it gives you a very
cool html folder with all there is to know about your code.
You can disable inspectors and configure them.