Here is the simplest possible Java program that runs a Groovy Script (as far as I know).

package affy.groovy.driver;

import groovy.lang.GroovyShell;

public class GroovyDriver {
 public static void main(String[] args) {
  new GroovyShell().evaluate("println('Hello World');");
 }
}

You'll need three jar files to make this program compile and execute:

  groovy-1.0.jar
  asm-2.2.jar
  antlr-2.7.5.jar

This warning also says that the javax.naming.NoInitialContextException was caused by a missing java.naming.factory.initial parameter. I am seeing this error while running an embedded ServiceMix engine. It is easy to fix however. You need to add two files to the classpath. jndi.properties

java.naming.factory.initial = org.apache.xbean.spring.jndi.SpringInitialContextFactory

jndi.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
  <bean id="jndi" class="org.apache.xbean.spring.jndi.DefaultContext">
    <property name="entries">
      <map/>
    </property>
  </bean>
</beans>