I've written a Sonar PMD extension plugin to add my custom written PMD ruleset into Sonar. It works perfectly fine. I also have written few rules where my rule type resolves to check whether my rule is applicable for a class or variable. In those cases, I have added the jars (which has those specific classes I look for) into my extension-plugin jar and it worked.
Now, I'm trying to write a rule where it checks a variable usage only if the type inherits from my interface. I used the same PMD TypeHelper and packaged the jar which contains my Interface. But, since the source code being analyzed is not loaded into the classpath, my TypeHelper is not really working.
This "How to write a PMD rule" page talks about Auxilary classpath. How to configure it when I'm running my analysis using Sonar MOJO. Also, it is possible to get it auto-configured with my maven project & its dependencies loaded into that?