Chunk, my no-nonsense template engine for Java, would be a good choice.
- Lightweight.
- Great docs with examples and recipes: http://www.x5software.com/chunk
- Standalone - no servlets required.
- Templates from filesystem, classpath, strings, a webserver, or write your own template provider.
- Based on simple templates with {$tags}.
- Templates can include other templates or even execute them as macros with a json-formatted dictionary of tag values.
- Looping, conditionals, filters, all the typical goodies.