assertFalse(validator.determineValid("invalid"));
        assertFalse(validator.determineValid("too many fields here * * * * * * *"));
        assertFalse(validator.determineValid("* * * *"));
    }

    public void test_isValid_basicInvalidCronExpression() {
        final ConstraintValidatorContext context = null;
        assertFalse(validator.isValid("invalid cron", context));

        assertFalse(iterator.hasNext());
        assertNull(iterator.next());

        verify(resource, never()).close();
    }

    @Test
    @DisplayName("Empty iterator")
    void emptyIterator() {
        when(delegate.hasNext()).thenReturn(false);

        TestIterator iterator = new TestIterator(null);

        assertFalse(iterator.hasNext());

        getMultiset().entrySet().remove(Multisets.immutableEntry(e0(), 1)));
    assertFalse("multiset contains element after removing its entry", getMultiset().contains(e0()));
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testEntrySet_removeAbsent() {
    assertFalse(
        "multiset.entrySet.remove(missingEntry) returned true",

        Name name = new Name(mockConfig, "TestName", 0x20, null);
        assertFalse(name.isUnknown());
    }

    @Test
    void isUnknown_withNonZeroHexCode_shouldReturnFalse() {
        Name name = new Name(mockConfig, "0.0.0.0", 0x20, null);
        name.scope = null;
        assertFalse(name.isUnknown());
    }

    @Test
    void isUnknown_withScope_shouldReturnFalse() {

    ExecutorService executor = newFixedThreadPool(1);
    requestInterruptIn(500);
    executor.execute(new SleepTask(10000));
    executor.shutdown();
    assertFalse(awaitTerminationUninterruptibly(executor, Duration.ofSeconds(1)));
    assertFalse(executor.isTerminated());
    assertInterrupted();
  }

  public void testTryAwaitTerminationUninterruptiblyLongTimeUnit_success() {

    }

    public void test_ofNullable_withNullString() {
        String testValue = null;
        OptionalEntity<String> result = OptionalUtil.ofNullable(testValue);

        assertNotNull(result);
        assertFalse(result.isPresent());
    }

    public void test_ofNullable_withEmptyString() {
        String testValue = "";
        OptionalEntity<String> result = OptionalUtil.ofNullable(testValue);

        assertFalse(user.isEditable());

        // Test with different user configurations
        user = new TestFessUser("admin", new String[] { "admin" }, new String[] { "admins" }, new String[] { "*" });
        assertFalse(user.isEditable());

        user = new TestFessUser("", new String[] {}, new String[] {}, new String[] {});
        assertFalse(user.isEditable());
    }

@GwtCompatible
public class MinimalIterableTest extends TestCase {

  public void testOf_empty() {
    Iterable<String> iterable = MinimalIterable.<String>of();
    Iterator<String> iterator = iterable.iterator();
    assertFalse(iterator.hasNext());
    assertThrows(NoSuchElementException.class, () -> iterator.next());
    assertThrows(IllegalStateException.class, () -> iterable.iterator());
  }

  public void testOf_one() {

        assertEquals(3, ruleManager.getRuleCount());

        ruleManager.clearRules();

        assertEquals(0, ruleManager.getRuleCount());
        assertFalse(ruleManager.hasRule(rule1));
        assertFalse(ruleManager.hasRule(rule2));
        assertFalse(ruleManager.hasRule(rule3));
    }

    /**
     * Test getRule call count
     */
    public void test_getRuleCallCount() {

        LeaseEntry noneEntry = leaseManager.getLease(noneKey);

        assertFalse(noneEntry.hasReadCache());
        assertFalse(noneEntry.hasWriteCache());
        assertFalse(noneEntry.hasHandleCache());
    }

    @Test
    @DisplayName("Should handle lease break with timeout")
    void testHandleLeaseBreakWithTimeout() {
        String path = "/share/timeout.txt";