public void collectClasses(ImmutableList.Builder<Class<?>> builder) {
        builder.add(unwrap());
    }

    @Override
    public String getRepresentation(boolean full) {
        try {
            return tryToGetRepresentation(full);
        } catch (NoClassDefFoundError ignore) {
            // This happens for IBM JDK 6 for nested interfaces -- see https://issues.apache.org/jira/browse/GROOVY-7010