assertEquals(errorCode, exception.getErrorCode(), "getErrorCode() should return the correct error code.");
    }

    /**
     * Test getRootCause() method (deprecated).
     */
    @Test
    void testGetRootCause() {
        Throwable cause = new IllegalArgumentException("Invalid argument.");
        DcerpcException exception = new DcerpcException("Error with cause.", cause);

        assertNull(bothNullException.getCause());
    }

    @Test
    @DisplayName("Test deprecated getRootCause method returns the same as getCause")
    @SuppressWarnings("deprecation")
    public void testGetRootCause() {
        // Test with no cause
        TransportException noCauseException = new TransportException("No cause");
        assertNull(noCauseException.getRootCause());

        }
    }

    @Nested
    @DisplayName("GetRootCause Tests")
    class GetRootCauseTests {

        @Test
        @DisplayName("Should return root cause when set")
        void testGetRootCause() {
            Exception rootCause = new IllegalStateException("Test root cause");
            TransportException exception = new TransportException("Message", rootCause);