class DefaultPropertySourceSnapshot implements PropertySource, Serializable {

    @Override
    public String toString() {
        return "FrozenPropertySource{" +
                "name=" + name +
                ", ordinal=" + ordinal +
                ", properties=" + properties +
                ", frozenAt=" + frozenAt +
                '}';
    }

    public  DefaultPropertySourceSnapshot(PropertySource propertySource);
    public  DefaultPropertySourceSnapshot(PropertySource propertySource, Iterable<String> keys);

}