Does anyone know of any Java library for programmatic web browsing?
Prowser doesn't cut it because there's no "push the button" method and Watij is limited to Internet Explorer Windows only.
htmlunit?
http://htmlunit.sourceforge.net/
The above link says:
... HtmlUnit is not a generic unit testing framework. It is specifically a way to simulate a browser for testing purposes...
You may be able to find some of what you want in Selenium and especially when using Selenium Server like in this IBM article
what do you want to accomplish? what problem are you solving? you might be able to write/find a web scraping java library to get the data that you want.