Knowing how to write Java is absolutely not needed at all. Knowing how to read Java can be useful depending on what libraries you need. The one thing that you have to learn no matter what is the basic IO classes, which are covered pretty well in http://copperthoughts.com/p/clojure-io-p1/.
Before the clojure.java.io namespaces was created, it used to be necessary to interact directly with those classes for even basic usage. (Kids these days! They've got it so easy.)
The web application ecosystem can be a bit intimidating to peace-loving programmers with all its talk of wars, but even that is changing with deployment options like Elastic Beanstalk and Heroku.
Anyway, you hear horror stories about Enterprise Java Beans, dependency injection frameworks, Maven, and whatnot, but you never see any of that in everyday Clojure.
Before the clojure.java.io namespaces was created, it used to be necessary to interact directly with those classes for even basic usage. (Kids these days! They've got it so easy.)
The web application ecosystem can be a bit intimidating to peace-loving programmers with all its talk of wars, but even that is changing with deployment options like Elastic Beanstalk and Heroku.
Anyway, you hear horror stories about Enterprise Java Beans, dependency injection frameworks, Maven, and whatnot, but you never see any of that in everyday Clojure.