public static boolean isEmpty(@SuppressWarnings("rawtypes") Collection collection) {
        return (collection == null || collection.isEmpty());
    }
@Test
    void collectionIsEmpty() {
        assertThat(CollectionUtil.isEmpty(null)).isTrue();
        assertThat(CollectionUtil.isEmpty(Collections.emptyList())).isTrue();
        assertThat(CollectionUtil.isEmpty(Collections.singletonList("test"))).isFalse();
    }