public boolean containsOperation(final K operationKey) {
        return registeredOperationTriggers.containsKey(operationKey)
                || completedOperations.getIfPresent(operationKey) != null;
    }
@Test
    void containsReturnsFalseForUnknownOperation() {
        assertThat(completedOperationCache.containsOperation(TEST_OPERATION_KEY)).isFalse();
    }