Parameter does not take effect for $mdm-match. count, onlyCertainMatches

[zero-zero-senven]

Describe the bug

I read the hl7 specification : patient-operation-match and found here should support more parameters, such as the count, I found not take effect at the time of use, and track the source code, find here is not to read the specified parameters, Is this a bug or is it unnecessary to deal with? (As far as I know, all matches were read and the data possible_match was possible_match. Is it necessary to apply count?)

Code

The code snippet in question：

public IBaseBundle getMatchesAndPossibleMatchesForResource(
			IAnyResource theResource, String theResourceType, RequestDetails theRequestDetails) {
		RequestPartitionId requestPartitionId;
		if (myMdmSettings.getSearchAllPartitionForMatch()) {
			requestPartitionId = RequestPartitionId.allPartitions();
		} else {
			requestPartitionId = myRequestPartitionHelperSvc.determineReadPartitionForRequestForSearchType(
					theRequestDetails, theResourceType);
		}
		List<MatchedTarget> matches =
				myMdmMatchFinderSvc.getMatchedTargets(theResourceType, theResource, requestPartitionId);
		matches.sort(
				Comparator.comparing((MatchedTarget m) -> m.getMatchResult().getNormalizedScore())
						.reversed());

		BundleBuilder builder = new BundleBuilder(myFhirContext);
		builder.setBundleField("type", "searchset");
		builder.setBundleField("id", UUID.randomUUID().toString());
		builder.setMetaField("lastUpdated", builder.newPrimitive("instant", new Date()));

		IBaseBundle retVal = builder.getBundle();
		for (MatchedTarget next : matches) {
			boolean shouldKeepThisEntry = next.isMatch() || next.isPossibleMatch();
			if (!shouldKeepThisEntry) {
				continue;
			}

			IBase entry = builder.addEntry();
			builder.addToEntry(entry, "resource", next.getTarget());

			IBaseBackboneElement search = builder.addSearch(entry);
			toBundleEntrySearchComponent(builder, search, next);
		}
		return retVal;
	}

code reference:

hapi-fhir/hapi-fhir-server-mdm/src/main/java/ca/uhn/fhir/mdm/provider/MdmControllerHelper.java

Line 142 in 41c2e49

public IBaseBundle getMatchesAndPossibleMatchesForResource(

To Reproduce

1. custom mdm-setting
2. call {baseUrl}/Patient/$match, and use complete parameter : resource, count,onlyCertainMatches
3. observe the number of matches returned