assertEquals("a,b,c=>output", item.toLineString());
    }

    public void test_toLineString_withUpdates() {
        String[] inputs = { "old1", "old2" };
        CharMappingItem item = new CharMappingItem(1L, inputs, "oldOutput");

        item.setNewInputs(new String[] { "new1", "new2", "new3" });
        item.setNewOutput("newOutput");

                v3(),
                (oldV, newV) -> {
                  assertEquals(v0(), oldV);
                  assertEquals(v3(), newV);
                  return null;
                }));
    expectMissing(e0());
  }

  public void testMergeNullValue() {
    try {
      getMap()
          .merge(
              k0(),
              null,
              (oldV, newV) -> {

                v3(),
                (oldV, newV) -> {
                  assertEquals(v0(), oldV);
                  assertEquals(v3(), newV);
                  return null;
                }));
    expectMissing(e0());
  }

  public void testMergeNullValue() {
    try {
      getMap()
          .merge(
              k0(),
              null,
              (oldV, newV) -> {

    if (listeners == expect) {
      listeners = update;
      return true;
    }
    return false;
  }

  final @Nullable Listener gasListeners(Listener update) {
    Listener old = listeners;
    listeners = update;
    return old;
  }

  static boolean casValue(AbstractFutureState<?> future, @Nullable Object expect, Object update) {
    if (future.value == expect) {
      future.value = update;
      return true;

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().remove(e0(), 0));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testRemove_occurrences_present() {
    assertEquals(
        "multiset.remove(present, 2) didn't return the old count",
        1,
        getMultiset().remove(e0(), 2));

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().remove(e0(), 0));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testRemove_occurrences_present() {
    assertEquals(
        "multiset.remove(present, 2) didn't return the old count",
        1,
        getMultiset().remove(e0(), 2));

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().add(e0(), 0));
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddOccurrences() {
    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().add(e0(), 2));
    assertEquals("old count", originalCount + 2, getMultiset().count(e0()));
  }

 *   <li>Old document deletion after successful crawling</li>
 *   <li>Crawling execution monitoring and timing</li>
 * </ul>
 */
public class DataIndexHelper {

    /** Logger instance for this class */
    private static final Logger logger = LogManager.getLogger(DataIndexHelper.class);

    /** Parameter key for controlling deletion of old documents */

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().add(e0(), 0));
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddOccurrences() {
    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().add(e0(), 2));
    assertEquals("old count", originalCount + 2, getMultiset().count(e0()));
  }

    }

    /**
     * Deletes old documents that have the same URL but different document IDs
     * as the documents in the provided list. This prevents duplicate documents
     * from accumulating in the index.
     *
     * @param searchEngineClient the search engine client to use for deletion
     * @param docList the list of new documents to check against
     * @return the number of old documents that were deleted
     */