A specialized "main" entry point that assumes it will run a specific file (jar-bootstrap.rb) when launching. This allows modifying only the manifest's Main-Class and adding this file to create a self-contained executable JRuby application. Example usage:

~/projects/jruby $ cp lib/jruby.jar myapp.jar

~/projects/jruby $ cat jar-bootstrap.rb
puts "hello"

~/projects/jruby $ jar ufe myapp.jar org.jruby.JarBootstrapMain jar-bootstrap.rb

~/projects/jruby $ java -jar myapp.jar
hello