@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());
        assertEquals(noCauseException.getCause(), noCauseException.getRootCause());

        // Test with cause

        assertEquals(expectedStatus, ex.getNtStatus(), "status should map based on code");
        assertNull(ex.getCause(), "cause must be null for int constructor");
        assertNull(ex.getRootCause(), "rootCause must be null for int constructor");
    }

    /**
     * Validate message-only constructor with both null and empty messages.
     */
    @ParameterizedTest
    @MethodSource("messageProvider")

    }

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

    /**

import org.mockito.junit.jupiter.MockitoExtension;

/**
 * Unit tests for {@link SmbException}.
 *
 * The tests exercise the public API: constructors, {@link #getNtStatus()},
 * {@link #getRootCause()}, and {@link #toString()}.
 */
@ExtendWith(MockitoExtension.class)
class SmbExceptionTest {

    /**
     * Happy path – constructor with a valid NT status code (0).
     */
    @Test

            assertEquals(msg, ex.getMessage(), "Message should be stored as provided");
        }
        assertSame(cause, ex.getCause(), "Cause should be stored and retrievable");
        assertSame(cause, ex.getRootCause(), "Deprecated getRootCause should match getCause");
        assertEquals(NtStatus.NT_STATUS_UNSUCCESSFUL, ex.getNtStatus(), "Status should default to unsuccessful for message+cause ctor");
    }

    public int getErrorCode() {
        return this.error;
    }

    /**
     *
     * @return the root cause
     * @deprecated use {@link #getCause()}
     */
    @Deprecated
    public Throwable getRootCause() {
        return getCause();
    }

        super(msg, rootCause);
    }

    /**
     * Gets the root cause of this exception.
     * @return root cause of this exception
     */
    @Deprecated
    public Throwable getRootCause() {
        return getCause();
    }

        this.rootCause = rootCause;
    }

    /**
     * Returns the root cause of this exception.
     *
     * @return the root cause or null if none was set
     */
    public Throwable getRootCause() {
        return rootCause;
    }

    @Override
    public String toString() {
        if (rootCause != null) {
            final StringWriter sw = new StringWriter();

     */
    public int getErrorCode() {
        return error;
    }

    /**
     * Returns the root cause of this exception
     *
     * @return the root cause throwable
     */
    public Throwable getRootCause() {
        return rootCause;
    }

    @Override
    public String toString() {
        if (rootCause != null) {
            final StringWriter sw = new StringWriter();

        assertEquals(NtStatus.NT_STATUS_UNSUCCESSFUL, ex.getNtStatus(), "Default NT status should be UNSUCCESSFUL");
        assertNull(ex.getCause(), "Cause should be null by default");
        assertNull(ex.getRootCause(), "Root cause should be null by default");
        assertTrue(ex instanceof SmbException, "Should be an SmbException subtype");
    }

    /**