Tapping into Ruby from the JVM

if options.fetch :squash, true
  result.shift && @lineno += 1 while (top = result[0]) && top.empty?
  result.pop while (bot = result[-1]) && bot.empty?
end

block {
  named :shout
  on_context :paragraph
  parse_content_as :simple
  name_attributes 'vol'
  process &-> (parent, reader, attrs) {
    volume = ((attrs.delete 'vol') || 1).to_i
    create_paragraph parent, (reader.lines.map {|line|
        line.upcase.gsub /\.(?= |$)/, '!' * volume }), attrs
  }
}

jit.threshold=10
jit.logging=true

$ jruby -J-server bench.rb

import org.jruby.embed.ScriptingContainer;
...
ScriptingContainer container = new ScriptingContainer();
container.runScriptlet("puts 'Hello from Ruby!'");

ScriptingContainer container = new ScriptingContainer();
container.put("message", "Hello from Ruby!");
container.runScriptlet("puts message");

ScriptingContainer container = new ScriptingContainer();
container.put("message", "Hello from Java with help from Ruby!");
IRubyObject result = container.runScriptlet("message.upcase");
System.out.println(result);

ScriptingContainer container = new ScriptingContainer();
Ruby runtime = container.getProvider().getRuntime();
String script = "require 'asciidoctor'\nAsciidoctor"
IRubyObject result = (IRubyObject) container.runScriptlet(script);
Asciidoctor asciidoctor = JavaEmbedUtils
    .rubyToJava(runtime, result, Asciidoctor.class);
String html = asciidoctor.convert_file("sample.adoc");

container.runScriptlet("require 'asciidoctor'")

$ \curl -sSL "https://get.rvm.io" > rvm-install.sh
  bash rvm-install.sh -s latest
  rvm install jruby
  rvm use jruby
  jruby --version