jruby emb

import org.jruby.Ruby;

import org.jruby.RubyRuntimeAdapter;

import org.jruby.javasupport.JavaEmbedUtils;  

{...}

// Create runtime instance

Ruby runtime = JavaEmbedUtils.initialize(new ArrayList());

RubyRuntimeAdapter evaler = JavaEmbedUtils.newRuntimeAdapter();

{...}

evaler.eval(runtime, "puts 1+2");

{...}

// Shutdown and terminate instance

JavaEmbedUtils.terminate(runtime);

https://github.com/jruby/jruby/wiki/DirectJRubyEmbedding