* @param columnKey column key that the value should be associated with
   * @param value value to be associated with the specified keys
   * @return the value previously associated with the keys, or {@code null} if no mapping existed
   *     for the keys
   */
  @CanIgnoreReturnValue
  @Nullable V put(
      @ParametricNullness R rowKey, @ParametricNullness C columnKey, @ParametricNullness V value);

  /**

   * @param columnKey column key that the value should be associated with
   * @param value value to be associated with the specified keys
   * @return the value previously associated with the keys, or {@code null} if no mapping existed
   *     for the keys
   */
  @CanIgnoreReturnValue
  @Nullable V put(
      @ParametricNullness R rowKey, @ParametricNullness C columnKey, @ParametricNullness V value);

  /**

        for (final UrlQueue<String> urlQueue : urlQueueList) {
            if (!exists(sessionId, urlQueue.getUrl()) && !dataService.exists(sessionId, urlQueue.getUrl())) {
                urlQueue.setSessionId(sessionId);
                targetList.add(urlQueue);
            } else if (logger.isDebugEnabled()) {
                logger.debug("Existed URL: Session ID: {}, UrlQueue: {}", sessionId, urlQueue);
            }
        }

   * in any particular order. The returned {@code Iterator} is a "weakly consistent" iterator that
   * will never throw {@link ConcurrentModificationException}, and guarantees to traverse elements
   * as they existed upon construction of the iterator, and may (but is not guaranteed to) reflect
   * any modifications subsequent to construction.
   *
   * @return an iterator over the elements in this queue
   */

   * Iterator} is a "weakly consistent" iterator that will never throw {@link
   * ConcurrentModificationException}, and guarantees to traverse elements as they existed upon
   * construction of the iterator, and may (but is not guaranteed to) reflect any modifications
   * subsequent to construction.
   *
   * @return an iterator over the elements in this queue in proper sequence
   */

   * are valid.
   *
   * @param rowKey row key of mapping to be erased
   * @param columnKey column key of mapping to be erased
   * @return the value previously associated with the keys, or {@code null} if no mapping existed
   *     for the keys
   */
  @CanIgnoreReturnValue
  public @Nullable V erase(@Nullable Object rowKey, @Nullable Object columnKey) {
    Integer rowIndex = rowKeyToIndex.get(rowKey);

   * are valid.
   *
   * @param rowKey row key of mapping to be erased
   * @param columnKey column key of mapping to be erased
   * @return the value previously associated with the keys, or {@code null} if no mapping existed
   *     for the keys
   */
  @CanIgnoreReturnValue
  public @Nullable V erase(@Nullable Object rowKey, @Nullable Object columnKey) {
    Integer rowIndex = rowKeyToIndex.get(rowKey);

errors.app.db.already.updated = Es posible que ya haya sido actualizado por otro proceso. Por favor, inténtelo de nuevo.
errors.app.db.already.exists = Los datos ya existen. Por favor, inténtelo de nuevo.
errors.app.double.submit.request = Es posible que esta solicitud ya se haya procesado. Por favor, inténtelo de nuevo.

errors.app.db.already.deleted = Pode ter sido excluído por outro processo. Por favor, tente novamente.
errors.app.db.already.updated = Pode ter sido atualizado por outro processo. Por favor, tente novamente.
errors.app.db.already.exists = Os dados já existem. Por favor, tente novamente.
errors.app.double.submit.request = Esta solicitação pode já ter sido processada. Por favor, tente novamente.

    assertLockHeld()

    if (initialized) {
      return // Already initialized.
    }

    // If a bkp file exists, use it instead.
    if (fileSystem.exists(journalFileBackup)) {
      // If journal file also exists just delete backup file.
      if (fileSystem.exists(journalFile)) {
        fileSystem.delete(journalFileBackup)
      } else {
        fileSystem.atomicMove(journalFileBackup, journalFile)