Hpricot

From JRubyWiki

Installing Hpricot

The current version of Hpricot found through RubyGems should now work with JRuby trunk.

To use Hpricot with JRuby 1.3+ you will need to run these commands

jruby -S gem install hpricot

You should see something like this

JRuby limited openssl loaded. gem install jruby-openssl for full support.
http://wiki.jruby.org/wiki/JRuby_Builtin_OpenSSL
Successfully installed hpricot-0.6.161-java
1 gem installed
Installing ri documentation for hpricot-0.6.161-java...
Installing RDoc documentation for hpricot-0.6.161-java...