// Arrange & Act
        SMBProtocolDowngradeException ex = new SMBProtocolDowngradeException();

        // Assert - message and cause are null
        assertNull(ex.getMessage(), "Default constructor should have null message");
        assertNull(ex.getCause(), "Default constructor should have null cause");

        // Assert - toString shows class name when message is null

    map.putInstance(Integer.class, null);
    assertNull(map.get(Integer.class));
    assertNull(map.getInstance(Integer.class));

    map.put(Long.class, null);
    assertNull(map.get(Long.class));
    assertNull(map.getInstance(Long.class));
  }

  public void testPrimitiveAndWrapper() {
    assertNull(map.getInstance(int.class));
    assertNull(map.getInstance(Integer.class));

                assertFalse(iterator3.hasNext(), "Third instance should have no elements");

                assertNull(iterator1.next(), "First instance next() should return null");
                assertNull(iterator2.next(), "Second instance next() should return null");
                assertNull(iterator3.next(), "Third instance next() should return null");
            } catch (CIFSException e) {

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3

import kotlin.test.Test
import kotlin.test.assertEquals
import kotlin.test.assertNull
import okhttp3.MediaType.Companion.toMediaTypeOrNull

/**
 * Test MediaType API and parsing.
 *
 * This test includes tests from [Guava's](https://code.google.com/p/guava-libraries/)
 * MediaTypeTest.
 */

        // These should return null
        assertNull(freshData.getDocumentItems());
        assertNull(freshData.getFacetResponse());
        assertNull(freshData.getAppendHighlightParams());
        assertNull(freshData.getExecTime());
        assertNull(freshData.getAllRecordCountRelation());
        assertNull(freshData.getPageNumberList());
        assertNull(freshData.getSearchQuery());

        assertNull(dfsImpl.getDc(mockContext, "anydomain.com"));
    }

    @Test
    void testGetDc_ConnectionFails() throws SmbAuthException {
        // Scenario: Transport connection fails when getting DC
        when(mockCredentials.getUserDomain()).thenReturn("authdomain.com");
        // When transport fails to connect, getDc returns null
        assertNull(dfsImpl.getDc(mockContext, "anydomain.com"));

    assertEquals("get(present) should return the associated value", v0(), get(k0()));
  }

  public void testGet_no() {
    assertNull("get(notPresent) should return null", get(k3()));
  }

  @MapFeature.Require(ALLOWS_NULL_KEY_QUERIES)
  public void testGet_nullNotContainedButAllowed() {
    assertNull("get(null) should return null", get(null));
  }

  @MapFeature.Require(absent = ALLOWS_NULL_KEY_QUERIES)

                (k, v) -> {
                  assertEquals(k3(), k);
                  assertNull(v);
                  return v3();
                }));
    expectAdded(e3());
    assertEquals(getNumElements() + 1, getMap().size());
  }

  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE})
  public void testCompute_absentToAbsent() {
    assertNull(
        "Map.compute(absent, functionReturningNull) should return null",

        assertNull(artifact.getVersion());
        assertNull(artifact.getBaseVersion());
    }

    @Test
    void testMNG7780() throws Exception {
        VersionRange vr = VersionRange.createFromVersionSpec("[1.0,2.0)");
        artifact = new DefaultArtifact(groupId, artifactId, vr, scope, type, null, artifactHandler);
        assertNull(artifact.getVersion());

    ValueReference<Object, Object> valueRef = map.newValueReference(entry, value, 1);
    entry.setValueReference(valueRef);

    assertNull(segment.get(key, hash));

    // count == 0
    table.set(index, entry);
    assertNull(segment.get(key, hash));
    assertFalse(segment.containsKey(key, hash));
    assertFalse(segment.containsValue(value));

    // count == 1