I been looking at using MediaWiki for a project but all that PHP was just killing and i did not want to start to learn another scripting language... so after a while I found the following wiki system JAMWiki
JAMWiki is a Wiki engine implemented using Java/JSP that attempts to provide much of the functionality of MediaWiki. It can be run with or without a database and is designed to be fast and easy to set up.
- Offers many of the features of MediaWiki
- Setup is quick and easy - no external database is required!
- Supports almost any application server running Java 5 or later.
- Utilizes the Spring Framework and Spring Security.
- Licensed under the GNU Lesser General Public License (LGPL).
Check it out at all the JAMWiki Features