This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Since you're asking for "collective wisdom", I'll confirm that Ireneusz is completely correct here - interfaces can never declare static methods. There's no way to do this in Java. The closest options I can think of are to either refactor to make the methods non-static, or add some reflection-based code that checks at runtime to see if a given class implements the methods you require. I don't see a way to do better.