Java: Map Contains Equals to or Less Than of Another Map

How do I check if 1 subset contains less than or equal to of another subset? SMap and TMap below.

In this example, doing equation returns false.

sMap.entrySet().containsAll(tMap.entrySet())

I believe it returns false, since it is trying equal the count of A,B,C. {1,2,2} does Not equal {1,1,1}. However, it should be true since {1,1,1} <= {1,2,2} for each element A,B,C.

Is there an easy method to doing a contains less than or equal to? Otherwise I will just write a manual for loop with count.

https://stackoverflow.com/questions/43217055/check-whether-a-map-contains-all-contents-of-another-map

https://stackoverflow.com/questions/33024356/verify-that-all-key-value-pairs-in-a-map-are-present-in-another-map

As I know, there is no built-in method to do what you desire, containsAll returns true when all the map entries from one map exist in another map.

But, as you said you can write such a method as below;

private static boolean containsAllCounts(Map<String, Integer> firstMap, Map<String, Integer> secondMap) {
    String key;
    int secondMapCount;
    for (Map.Entry<String, Integer> entry : secondMap.entrySet()) {
        key = entry.getKey();
        secondMapCount = entry.getValue();
        if (!firstMap.containsKey(key) || firstMap.get(key) <= secondMapCount) {
            return false;
        }
    }
    return true;
}

When there are two maps as below;

    Map<String, Integer> firstMap = new HashMap<>();
    firstMap.put("A", 2);
    firstMap.put("B", 2);
    firstMap.put("C", 1);

    Map<String, Integer> secondMap = new HashMap<>();
    secondMap.put("A", 1);
    secondMap.put("B", 1);

    System.out.println(containsAllCounts(firstMap, secondMap));
    System.out.println(containsAllCounts(secondMap, firstMap));

Outputs will be;

true
false

The equal method will compare the hash and therefore only for equality. I am not aware of a build in function, but with an allMatch on the stream you could do a compare easily on your own...

With allMatch (thanks to @shmosel):

    tMap.entrySet()
         .stream()
         .allMatch(e -> sMap.containsKey(e.getKey()) && sMap.get(e.getKey()) >= e.getValue())

---- edited, originally I had the noneMatch example but allMatch is easier to understand...for completeness, I still include the noneMatch example -----

    tMap.entrySet().stream().noneMatch(entry -> {
        final Integer match = sMap.get(entry.getKey());
        return match == null || entry.getValue() > match;
    });

or if you prefer it as a one-liner

    tMap.entrySet()
        .stream()
        .noneMatch(entry -> !sMap.containsKey(entry.getKey()) || entry.getValue() > sMap.get(entry.getKey()));

The matcher will check for any unmatched key or value from tMap, that is greater than the value in sMap.