It says:
JAVA-W1035 Classes that contain only static members should not be instantiated
for e.g. new TestID(UnsignedLong.MAX_VALUE.longValue(), "test") here as well as e.g. return Optional.of(new TestID(kind, data)); here…
… but that’s wrong, as that TestID is a Java 14+ record (not a class), so it’s correct.