The LGPL and Java "FSF's position has remained constant throughout: the LGPL works as intended with all known programming languages, including Java. Applications which link to LGPL libraries need not be released under the LGPL. Applications need only follow the requirements in section 6 of the LGPL: allow new versions of the library to be linked with the application; and allow reverse engineering to debug this."
"If you distribute a Java application that imports LGPL libraries, it's easy to comply with the LGPL. Your application's license needs to allow users to modify the library, and reverse engineer your code to debug these modifications. This doesn't mean you need to provide source code or any details about the internals of your application. Of course, some changes the users may make to the library may break the interface, rendering the library unable to work with your application. You don't need to worry about that -- people who modify the library are responsible for making it work."