}

    @Test
    @DisplayName("encode should throw NPE on null input")
    void testEncodeNull() {
        assertThrows(NullPointerException.class, () -> Base64.encode(null));
    }

    @Test
    @DisplayName("decode should throw NPE on null input")
    void testDecodeNull() {
        assertThrows(NullPointerException.class, () -> Base64.decode(null));
    }

    }

    /**
     * Test contains method with null list
     */
    @Test
    @DisplayName("Contains should return false for null list")
    void testContainsNullList() {
        assertFalse(AvPairs.contains(null, AvPair.MsvAvFlags), "Should return false for null list");
    }

    /**
     * Test contains method with empty list
     */
    @Test

    }

    /**
     * Test constructor with both null message and null cause
     */
    public void test_constructor_withNullMessageAndNullCause() {
        CrawlerSystemException exception = new CrawlerSystemException(null, null);

        assertNotNull(exception);
        assertNull(exception.getMessage());
        assertNull(exception.getCause());
    }

    /**

            assertTrue(s1.isEmpty());
            // isBlank will fail if sub_authority is null, so we skip that check for s1

            // All-zero subauthorities
            byte[] ident = new byte[] { 0, 0, 0, 0, 0, 0 };
            rpc.sid_t st = buildSidT((byte) 1, ident, 0, 0);
            SID s2 = new SID(st, jcifs.SID.SID_TYPE_USE_NONE, null, null, false);
            assertFalse(s2.isEmpty());
            assertTrue(s2.isBlank());

        this.outputData = this.outputBuffer == null ? createOutputDecodable() : null;

        if (this.inputData != null) {
            this.inputData.decode(buffer, inputOffset, inputCount);
        }
        bufferIndex = Math.max(inputOffset + inputCount, bufferIndex);

        if (this.outputBuffer != null) {
            if (outputCount > this.outputBuffer.length) {

    protected AbstractArtifactResolutionException(String message, Artifact artifact) {
        this(message, artifact, null);
    }

    protected AbstractArtifactResolutionException(
            String message, Artifact artifact, List<ArtifactRepository> remoteRepositories) {
        this(message, artifact, remoteRepositories, null);
    }

    protected AbstractArtifactResolutionException(

      ImmutableMapEntry<K, V> effectiveEntry =
          checkNoConflictInKeyBucket(key, value, keyBucketHead, throwIfDuplicateKeys);
      if (effectiveEntry == null) {
        // prepend, not append, so the entries can be immutable
        effectiveEntry =
            (keyBucketHead == null)
                ? makeImmutable(entry, key, value)
                : new NonTerminalImmutableMapEntry<K, V>(key, value, keyBucketHead);

        assertEquals(1, chain3.updateCallCount);
    }

    // Test addChain null handling
    public void test_addChain_withNull() {
        // ArrayUtils.addAll handles null gracefully by adding it to the array
        authenticationManager.addChain(null);

        // Verify null chain doesn't cause issues during operations
        User user = createTestUser("testuser");
        try {

    @Test
    @DisplayName("Test sign method with null request and response")
    void testSignWithNullMessages() {
        // Arrange
        int offset = 0;
        int length = testData.length;

        // Act
        signingDigest.sign(testData, offset, length, null, null);

        // Assert
        verify(signingDigest, times(1)).sign(testData, offset, length, null, null);
    }

    @Test

                    }
                }
                exception = null;
                break;
            } catch (final Exception e) {
                exception = new SuggesterException(e);
                scrollId = null;
            }
        }

        docCount.getAndAdd(queue.size());

        if (exception != null) {
            throw exception;
        }
    }

    /**