Simply, are there any Java Developer specific Linux distros?
A real Sun geek would chime in here about the virtues of using Solaris as a Java development platform, but I am much more ambivalent. Developing with Java is about the same on any linux distro; you are going to wind up having to install the JDK and tools of your choosing (Eclipse, Sun Studio, Tomcat, etc) so you may as well choose a distro on other criteria... perhaps how comfortable you are with it, how easy package management is, and if the look & feel suit your development habits are all big factors.
So, to answer your question more directly, a Java developer would do well with any major linux distro that they are comfortable with using in general. If you want some Java goodness out of the box, Fedora 9 and Ubuntu 8.04 have OpenJDK (and NetBeans) according to a recent announcement.