Few of the TokenFilterFactories are documented at all. Some of them have a simple XML config snippet example. Take the StandardTokenFilterFactory. It had no class JavaDoc until two days ago, when Koji and yourself added an xml snippet.
Thats not really correct: typically they have a link to the tokenfilter, for example here is ThaiWordFilterFactory.
). if they take arguments, then typically they describe what those arguments do.
This is enough, because someone can click the ThaiWordFilter and get all the details there.
The javadocs for the factory need only document the factory.
I think a reasonable goal, at least for these plugin type of classes, is to use the JavaDoc as the official main doc and point from Wiki to there. But then the Class-level JavaDoc must give a short introduction to what the filter does, when it is typically used along with a list of all valid parameters and their values.
I really don't think we should duplicate documentation from any Tokenizers/Filters into the factories. The factory should just have a javadoc ref to what it produces, and explain its various parameters. In other words, it need only document itself.
Any other documentation is actually redundant and problematic, as long as this javadoc exists it increases the maintenance load around here with no benefits to the user at all.