"Way better than Java's. Way better than any documentation that I saw before ..."
It is more close to reality and fair to put it in this way: If we are talking about the document for each module, Java's is better than Perl's in most cases; but Java lacks the kind of documentation like perltoot, perlfaq etc., which put things together for you.
When you read Java document, you may get a very clear picture of what the module is doing but it does not usually contain information as how to use the module in an application with other related modules.
However, the other side of the life is that, there are big knowledge bases for both languages on internet and in book stores beyond pure documentation.