PMD is a source code analyzer. It finds common programming flaws like unused variables, empty catch blocks,
Modelica, PLSQL, Apache Velocity, XML, XSL, Scala.
Additionally it includes CPD, the copy-paste-detector. CPD finds duplicated code in
Objective-C, Perl, PHP, PLSQL, Python, Ruby, Salesforce.com Apex, Scala, Swift and Visualforce.