}

    /**
     * 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.");
    }

    /**

    SomeCheckedException exception = new SomeCheckedException();
    assertThat(getRootCause(exception)).isSameInstanceAs(exception);
  }

  public void testGetRootCause_singleWrapped() {
    SomeCheckedException cause = new SomeCheckedException();
    SomeChainingException exception = new SomeChainingException(cause);
    assertThat(getRootCause(exception)).isSameInstanceAs(cause);
  }

    SomeCheckedException exception = new SomeCheckedException();
    assertThat(getRootCause(exception)).isSameInstanceAs(exception);
  }

  public void testGetRootCause_singleWrapped() {
    SomeCheckedException cause = new SomeCheckedException();
    SomeChainingException exception = new SomeChainingException(cause);
    assertThat(getRootCause(exception)).isSameInstanceAs(cause);
  }

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

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

        // Test with cause

        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();

        super(msg, rootCause);
    }

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

            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");
    }

            assertEquals(rootCause, exception.getRootCause());
        }

        @Test
        @DisplayName("Should handle null root cause")
        void testConstructorWithNullRootCause() {
            TransportException exception = new TransportException((Throwable) null);

            assertNotNull(exception);
            assertNull(exception.getRootCause());
        }

        @Test

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