factories.add(factory);
      }
    }
    if (!Modifier.isAbstract(type.getRawType().getModifiers())) {
      for (Constructor<?> constructor : type.getRawType().getDeclaredConstructors()) {
        Invokable<T, T> invokable = type.constructor(constructor);
        if (!invokable.isPrivate() && !invokable.isSynthetic()) {
          factories.add(invokable);
        }
      }
    }

        // Test constructor with null message
        SearchQueryException exception = new SearchQueryException((String) null);

        assertNull(exception.getMessage());
        assertNull(exception.getCause());
        assertTrue(exception instanceof FessSystemException);
    }

    @Test
    public void test_constructorWithNullCause() {
        // Test constructor with null cause

    public void test_constructor_withCause() {
        // Test constructor with cause only
        Throwable cause = new IllegalStateException("Container initialization failed");
        ContainerNotAvailableException exception = new ContainerNotAvailableException(cause);

        assertEquals("Container is not available.", exception.getMessage());
        // The cause is not passed to super constructor in the implementation
        assertNull(exception.getCause());

        // Test constructor with null cause
        final JobProcessingException exception = new JobProcessingException((Throwable) null);

        assertNotNull(exception);
        assertNull(exception.getCause());
        assertNull(exception.getMessage());
    }

    @Test
    public void test_constructor_withNullMessageAndCause() {
        // Test constructor with null message and cause

        byte[] raw = new byte[] { 0x01, 0x02, 0x03, 0x04 };
        AvPair avPair = new AvPair(type, raw);

        assertEquals(type, avPair.getType(), "Type should match the constructor argument.");
        assertArrayEquals(raw, avPair.getRaw(), "Raw data should match the constructor argument.");

        // Test with another type and empty raw data
        int type2 = AvPair.MsvAvEOL;
        byte[] raw2 = new byte[] {};

        // Test the no-argument constructor
        ConnectionTimeoutException exception = new ConnectionTimeoutException();
        assertNull(exception.getMessage(), "Message should be null for no-arg constructor");
        assertNull(exception.getCause(), "Cause should be null for no-arg constructor");
    }

    @Test
    void testStringConstructor() {
        // Test the constructor with a message

        // 1. Class should have protected constructor
        Constructor<?>[] constructors = ThreadDumpUtil.class.getDeclaredConstructors();
        assertEquals("Should have exactly one constructor", 1, constructors.length);
        assertTrue("Constructor should be protected", java.lang.reflect.Modifier.isProtected(constructors[0].getModifiers()));

        // 2. All public methods should be static

    @Test
    void testNoArgsConstructor() {
        // Test the constructor with no arguments
        RequestTimeoutException exception = new RequestTimeoutException();
        assertNull(exception.getMessage(), "Message should be null for no-arg constructor");
        assertNull(exception.getCause(), "Cause should be null for no-arg constructor");
    }

    @Test
    void testMessageConstructor() {

        // Then
        // Verify that the super constructor is called with correct arguments
        // Note: Directly verifying super constructor calls is not straightforward in JUnit/Mockito.
        // We verify the effects of the super constructor by checking the fields of the created object.

        // Assert object_attributes fields

        // Verify that SystemUtil has a private constructor (utility class pattern)
        try {
            Constructor<SystemUtil> constructor = SystemUtil.class.getDeclaredConstructor();
            assertTrue("Constructor should be private", java.lang.reflect.Modifier.isPrivate(constructor.getModifiers()));

            // Test that constructor is accessible when made accessible
            constructor.setAccessible(true);