@Test
    void verifyWrap() {
        assertNotNull(CollectionUtils.wrap((Map) null));
        assertNotNull(CollectionUtils.wrap((Multimap) null));
        assertNotNull(CollectionUtils.wrap(List.of()));

        assertNotNull(CollectionUtils.asMultiValueMap(Map.of()));
        assertNotNull(CollectionUtils.asMultiValueMap("key", "value"));
        assertNotNull(CollectionUtils.convertDirectedListToMap(List.of("key->value")));

        assertNotNull(CollectionUtils.wrap("1", "1", "2", "2", "3", "3",
            "4", "4", "5", "5", "6", "6", "7", "7",
            "8", "8", "9", "9"));
    }
This is {@link CollectionUtilsTests}.

@author Misagh Moayyed
@since 5.2.0
core/cas-server-core-util/src/test/java/org/apereo/cas/util/CollectionUtilsTests.java