Checkstyle is a development tool to help developers write

Java code that adheres to a coding standard. It automates

the process of checking Java code.

This makes it ideal for projects that want to enforce a

coding standard. 
Checkstyle can check many aspects of the source code.

It can find class design problems, method design problems.

It also has the ability to check code layout and formatting

issues. 
http://checkstyle.sourceforge.net/

Added checkstyle as tool and saw that it finds correct "errors".