NMCS_NEEDLESS_MEMBER_COLLECTION_SYNCHRONIZATION false positive

[djelinski]

computeIfAbsent is not listed as modifyingMethod; as a result the following piece of code generates a false positive:

public abstract class CacheFbBug {

	private final Map<String, String> hashableStringCache;

	public CacheFbBug() {
		hashableStringCache = Collections.synchronizedMap(new HashMap<>());
	}

	public String getHashedString(String val) {
		return hashableStringCache.computeIfAbsent(val, this::hashString);
	}

	public abstract String hashString(String stringToHash);
}

[djelinski]

looking at https://download.java.net/java/early_access/jdk15/docs/api/java.base/java/util/Map.html I see a few more methods missing:

• compute
• computeIfAbsent
• computeIfPresent
• merge
• putAll
• putIfAbsent
• replace
• replaceAll

[andrei-ivanov]

would be nice to get this fixed 👍