Method unmodifiableMultiMap

src/main/java/pascal/taie/util/collection/Maps.java:113–118

(MultiMap<K, V> map)

    }

    public static <K, V> MultiMap<K, V> unmodifiableMultiMap(MultiMap<K, V> map) {
        if (map instanceof UnmodifiableMultiMap<K, V>) {
            return map;
        }
        return new UnmodifiableMultiMap<>(map);
    }

    @SuppressWarnings("rawtypes")
    private static final MultiMap EMPTY_MULTIMAP = unmodifiableMultiMap(newMultiMap());