}
    }

    public FilteringClassLoader(ClassLoader parent, Spec spec) {
        super(parent);
        packageNames = new HashSet<String>(spec.packageNames);
        packagePrefixes = new TrieSet(spec.packagePrefixes);
        resourceNames = new HashSet<String>(spec.resourceNames);
        resourcePrefixes = new TrieSet(spec.resourcePrefixes);
        classNames = new HashSet<String>(spec.classNames);

            spec.classNames == [Test.name]
            spec.disallowedClassNames == [Before.name]
            spec.packageNames == ["org.junit"]
            spec.packagePrefixes == ["org.junit."]
            spec.resourceNames == ["a/b/c"]
            spec.resourcePrefixes == ["org/junit/"]
        }
        1 * visitor.visitParent(classLoader.parent)
        0 * visitor._
    }