How many times have you ran a Checkstyle ruleset against your Java code, investigated a problem line, and then wanted to scream out "but I did it the way it's supposed to be done!" If you're me, the answer is many. Additionally, some of the suggestions Checkstyle makes can leave you scratching your head, depending on how many of the more esoteric rules have been enabled.

One particular rule I have been wrestling with for some time now states, for each public method (paraphrasing here):

"This method must be declared as either abstract, final or have an empty implementation."

It's not immediately clear (unless you wrote this rule) why this is required. But then I discovered this wonderful index, which made it all clear. Using this index, you can lookup each of the generic Checkstyle warnings and see their justification.

So the war is over, Checkstyle and I have made peace now that I can determine the impetus behind its often cryptic warnings.