Agree about Java. Learning Java helps too. Very much. You don't even need to read all the book, cause a lot of it is about Java classes. Just read language concepts.

The main point is: perl allows you to do anything anyhow and it works. Java forces you to use OOP. Reading, some helloworld codings with change your POV to the coding at all.

And after that you see that perl is really awesome (except exceptions). You may make fast and dirty, or you may do correct way and let's say 'enterprise'. Depending on goals.