Using a java framework that defines a class like this public class FrameworkComponent { // lots of fields // lots of methods public final Object getProperty(String name) { return frameworkStuff.get(name); } // lots of other fields // lots of other methods } If one tries to create a Groovy class that extends this FrameworkComponent like the following: class MyComponent extends FrameworkComponent { def size = 10 } the groovy compiler raises an error saying that MyComponent overrides final method getProperty(String name) from FrameworkComponent. Attached to this issue follows bug.zip containing a mockup of this framework and a Groovy class that extends the framework class. To reproduce the error just unzip the file, navigate to the unzipped folder and fire: groovyc -cp framework.jar MyComponent.groovy it will raise the following error lines org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed, MyComponent.groovy: -1: You are not allowed to overwrite the final method getProperty(java.lang.String) from class 'FrameworkComponent'. @ line -1, column -1. 1 error