This week's book giveaway is in the OCAJP forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide 1Z0-808 and have Jeanne Boyarsky & Scott Selikoff on-line! See this thread for details.
What do you mean by "it uses either ..."? My impression of Maven is that it is a souped-up Ant, so you can start your own tasks in whichever way you like. Both PMD and Checkstyle have their own Ant task, and can alternatively be started using the <java> task. Does Maven not allow you to run several tasks of your own choice in succession, or does it support neither custom Ant tasks nor the <java> task?