Well, honestly, I'm not really that curious.
But, is it likely to be on the test? I don't feel like I really understand the details, and Lyons' discussion is *very* brief with no examples given. Do I need to go get the API dox on this topic to be ready for the exam?
I was going to elaborate, but since you're not interested
But no, it won't be on the exam because it's really a container fudge and not a fundamental concept. In practise, you only need to know one fact about it to develop cooperating tags: if your tag is a classic tag which has a SimpleTag as its parent, when you invoke getParent() you will get an instance of TagAdapter which contains the parent SimpleTag, and not the SimpleTag itself. To extract the actual SimpleTag parent, call the getAdaptee() method. Such a code segment in a classic tag might look like:
In practise this is usually unimportant as you'll develop cooperating tags usually either all as SimpleTags or all as classic tags.
BTW, the API docs really aren't any more detailed than the few paragraphs in my book, or what I've just mentioned above. You're not missing out!