Lobo is an open source web browser that is written completely in Java. Lobo is being actively developed with the aim to fully support HTML 4, Javascript and CSS2. Lobo also supports direct JavaFX rendering. It can also be used as an API.
Link to Free Download: Lobo Java Web Browser (http://www.theinfostride.com/forum/index.php?action=downloads;sa=view;down=93)