private final Class<? extends Compiler<GroovyJavaJointCompileSpec>> compilerClass;
    private final static Iterable<String> SHARED_PACKAGES = Arrays.asList("groovy", "org.codehaus.groovy", "groovyjarjarantlr", "groovyjarjarasm", "groovyjarjarcommonscli", "org.apache.tools.ant", "com.sun.tools.javac");
    private final ClassPathRegistry classPathRegistry;
    private final ClassLoaderRegistry classLoaderRegistry;
    private final JavaForkOptionsFactory forkOptionsFactory;