@Override
    public Collection<V> values() {
        Collection<V> values = Sets.newHashSet();
        items.values().forEach(v -> values.add(serializer.decode(v)));
        return values;
    }
@Test
    public void testValues() throws Exception {
        //Tests value set generation
        fillMap(10);
        Set<Integer> values = (Set<Integer>) map.values();
        for (int i = 0; i < 10; i++) {
            assertTrue("The key set doesn't contain all keys 0-9", values.contains(i));
        }
        assertEquals("The key set has an incorrect number of entries", 10, values.size());
    }