}

    @Test
    @DisplayName("Test Response interface methods - setExpiration")
    void testSetExpiration() {
        // Given
        Long expiration = System.currentTimeMillis() + 60000L;
        doNothing().when(response).setExpiration(expiration);

        // When
        response.setExpiration(expiration);

        // Then
        verify(response).setExpiration(expiration);

        when(mockResponse.getExpiration()).thenReturn(expiration);
        assertEquals(expiration, mockResponse.getExpiration());

        // Test null expiration
        when(mockResponse.getExpiration()).thenReturn(null);
        assertNull(mockResponse.getExpiration());

        // Verify the method was called
        verify(mockResponse, times(2)).getExpiration();
    }

    @Test

            Long expiration = 1000L;
            echoResponse.setExpiration(expiration);
            assertEquals(expiration, echoResponse.getExpiration());

            echoResponse.setExpiration(null);

            assertNull(echoResponse.getExpiration());
        }
    }

    @Nested
    @DisplayName("Signature Verification Tests")
    class SignatureVerificationTests {

        @Test

    /**
     * Gets the expiration time for this response.
     *
     * @return the message timeout
     */
    Long getExpiration();

    /**
     * Sets the expiration time for this response.
     *
     * @param exp the message timeout to set
     */
    void setExpiration(Long exp);

    /**
     * Resets this response to its initial state.
     */
    void reset();

    /**

            Long expiration = 1000L;

            response.setExpiration(expiration);

            assertEquals(expiration, response.getExpiration());
        }

        @Test
        @DisplayName("Should handle null expiration")
        void testNullExpiration() {
            response.setExpiration(null);

            assertNull(response.getExpiration());
        }
    }

    @Nested

     * {@inheritDoc}
     *
     * @see jcifs.util.transport.Response#getExpiration()
     */
    @Override
    public Long getExpiration() {
        return this.expiration;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.util.transport.Response#setExpiration(java.lang.Long)
     */
    @Override
    public void setExpiration(final Long exp) {
        this.expiration = exp;
    }

        }

        @Override
        public void error() {
            this.errorCode = -1;
        }

        @Override
        public Long getExpiration() {
            return expiration;
        }

        @Override
        public void setExpiration(Long exp) {
            this.expiration = exp;
        }

        @Override
        public Exception getException() {
            return exception;

        }

        @Test
        @DisplayName("Test expiration property")
        void testExpirationProperty() {
            assertNull(testBlock.getExpiration());
            testBlock.setExpiration(123456789L);
            assertEquals(123456789L, testBlock.getExpiration());
        }
    }

    @Nested
    @DisplayName("DFS Resolution Tests")
    class DFSResolutionTests {

        @BeforeEach

        public Exception getException() {
            return this.exception;
        }

        @Override
        public void setExpiration(Long expiration) {
            this.expiration = expiration;
        }

        @Override
        public Long getExpiration() {
            return this.expiration;
        }

        // Additional Response interface methods
        @Override

            if (firstKey == 0) {
                firstKey = k;
            }

            if (timeout > 0) {
                curResp.setExpiration(System.currentTimeMillis() + timeout);
            } else {
                curResp.setExpiration(null);
            }

            curResp.setMid(k);
            this.response_map.put(k, curResp);

            final Request next = curReq.getNext();