Let me first explain what I have understood about scripting variables.
<myTag:showMovies>
${movie} ---> movie is a scripting variable.
</myTag:showMovies>
According to
Mock by Eduardo Cobian question #2.
What are correct statements about creating scripting variables for a Tag::
1) It is necessary to implement TagExtraInfo interface.
2) You have to insert into the tag element of the taglib descriptor file an entry for tei-class element.
3) The interface you have to implement has a method called getVariableInfo.
Answer is 1,2 and 3.
Now I read HFSJ 2nd edition that has that famous example about evaluating the simple and classic tags bodies in a loop. Which is excatly similar to the above example. But HFSJ does not talk about <teiclass/> and TagExtraInfo class.
1) My question is are both similar
2) If yes then why is there no mention about TagExtraInfo
3) Is TagExtraInfo on SCWCD exam?
4) I have seen how to use the TagExtraInfo class where my class inhertied TagExtraInfo and getVariableInfo() was overriden, The thing i did not understand was when will TagExtraInfo methods be invoked?