Map<K, V> delegate = delegateOrNull();
    if (delegate != null) {
      return delegate.get(key);
    }
    int index = indexOf(key);
    if (index == -1) {
      return null;
    }
    accessEntry(index);
    return value(index);
  }

  @CanIgnoreReturnValue
  @SuppressWarnings("unchecked") // known to be a V
  @Override
  public @Nullable V remove(@Nullable Object key) {

    /** The key of the configuration. e.g. fess_config */
    String INDEX_CONFIG_INDEX = "index.config.index";

    /** The key of the configuration. e.g. fess_user */
    String INDEX_USER_INDEX = "index.user.index";

    /** The key of the configuration. e.g. fess_log */
    String INDEX_LOG_INDEX = "index.log.index";

        final int index = indexOf(array, obj);
        if (index < 0) {
            return array;
        }
        @SuppressWarnings("unchecked")
        final T[] newArray = (T[]) Array.newInstance(array.getClass().getComponentType(), array.length - 1);
        if (index > 0) {
            System.arraycopy(array, 0, newArray, 0, index);
        }
        if (index < array.length - 1) {

     */
    PropertyDesc getPropertyDesc(String propertyName);

    /**
     * Returns the {@link PropertyDesc}.
     *
     * @param index
     *            The index of the {@link PropertyDesc}
     * @return {@link PropertyDesc}
     */
    PropertyDesc getPropertyDesc(int index);

    /**
     * Returns the number of {@link PropertyDesc}.
     *
     * @return The number of {@link PropertyDesc}
     */

    return cellRowIndices.length;
  }

  @Override
  Cell<R, C, V> getCell(int index) {
    int rowIndex = cellRowIndices[index];
    Entry<R, ImmutableMap<C, V>> rowEntry = rowMap.entrySet().asList().get(rowIndex);
    ImmutableMap<C, V> row = rowEntry.getValue();
    int columnIndex = cellColumnInRowIndices[index];
    Entry<C, V> colEntry = row.entrySet().asList().get(columnIndex);

    return delegateList;
  }

  @SuppressWarnings("unchecked") // safe covariant cast!
  @Override
  public UnmodifiableListIterator<E> listIterator(int index) {
    return (UnmodifiableListIterator<E>) delegateList.listIterator(index);
  }

  @GwtIncompatible // not present in emulated superclass
  @Override
  int copyIntoArray(@Nullable Object[] dst, int offset) {

import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotNull;

import java.util.Iterator;

import org.codelibs.core.exception.ClUnsupportedOperationException;

/**
 * {@link Iterator} with index. The index starts from {@literal 0}.
 *
 * <p>
 * Usage example:
 * </p>
 *
 * <pre>
 * import static org.codelibs.core.collection.IndexedIterator.*;
 *
 * List&lt;String&gt; list = ...;

    runRemoveTest(getNumElements() - 1);
  }

  private void runRemoveTest(int index) {
    assertEquals(
        Platform.format("remove(%d) should return the element at index %d", index, index),
        getList().get(index),
        getList().remove(index));
    List<E> expected = copyToList(createSamplesArray());
    expected.remove(index);
    expectContents(expected);
  }

/**
 * Callback interface for handling index update operations during data store processing.
 * This interface provides methods for storing documents, tracking processing metrics,
 * and committing changes to the search index.
 */
public interface IndexUpdateCallback {

    /**
     * Stores a document in the search index with the specified parameters and data.
     *

    public boolean hasNext() {
        for (; index < iterators.length; ++index) {
            if (iterators[index].hasNext()) {
                return true;
            }
        }
        return false;
    }

    @Override
    public E next() {
        if (!hasNext()) {
            throw new NoSuchElementException();
        }
        return iterators[index].next();
    }

    @Override