/usr/bin/jirb
/usr/bin/jrubyc
/usr/bin/jruby
/usr/bin/jruby.rb
/usr/lib/jruby/bin/ast
/usr/lib/jruby/bin/gem
/usr/lib/jruby/bin/generate_yaml_index.rb
/usr/lib/jruby/bin/jgem
/usr/lib/jruby/bin/jirb
/usr/lib/jruby/bin/jirb_swing
/usr/lib/jruby/bin/jrubyc
/usr/lib/jruby/bin/jruby
/usr/lib/jruby/bin/rdoc
/usr/lib/jruby/bin/ri
/usr/lib/jruby/bin/testrb
You may install this package on Debian with
apt-get
install jruby