javasphinx is an extension to the Sphinx documentation system which adds support for documenting Java projects. It includes a Java domain for writing documentation manually and a javasphinx-apidoc utility which will automatically generate API documentation from existing Javadoc markup.
javasphinx is available in the Python Package Index (PyPi) under the name javasphinx and can be installed using tools such as pip or easy_install.
Documentation for javasphinx is available at http://bronto.github.com/javasphinx/