*/
    public void store(final User user) {
        final String username = user.getName();
        final boolean isUpdate = StringUtil.isNotBlank(user.getId());

        if (logger.isDebugEnabled()) {
            logger.debug("User {} operation initiated: username={}, id={}", isUpdate ? "update" : "create", username,
                    user.getId() != null ? user.getId() : "new");
        }

        try {

     * @return true if updated, false otherwise
     */
    public boolean isUpdated() {
        return newInput != null;
    }

    /**
     * Checks if this item has been deleted.
     * @return true if deleted, false otherwise
     */
    public boolean isDeleted() {
        return isUpdated() && newInput.length() == 0;
    }

    @Override
    public int hashCode() {

    }

    /**
     * Checks whether this mapping item has pending updates.
     *
     * @return true if both newInputs and newOutput are not null, indicating pending updates
     */
    public boolean isUpdated() {
        return newInputs != null && newOutput != null;
    }

    /**
     * Checks whether this mapping item is marked for deletion.

     */
    public boolean isUpdated() {
        return newInput != null;
    }

    /**
     * Checks if the item has been marked for deletion.
     *
     * @return true if the item is marked for deletion, false otherwise.
     */
    public boolean isDeleted() {
        return isUpdated() && newInput.length() == 0;
    }

    @Override

     */
    public boolean isUpdated() {
        return newInputs != null && newOutputs != null;
    }

    /**
     * Checks if the item has been marked for deletion.
     *
     * @return true if the item is marked for deletion, false otherwise.
     */
    public boolean isDeleted() {
        return isUpdated() && newInputs.length == 0;
    }

    @Override

         */
        public KuromojiItem write(final KuromojiItem oldItem) {
            try {
                if (item == null || item.getId() != oldItem.getId() || !item.isUpdated()) {
                    writer.write(oldItem.toLineString());
                    writer.write(Constants.LINE_SEPARATOR);
                    return oldItem;
                }

         */
        public CharMappingItem write(final CharMappingItem oldItem) {
            try {
                if (item == null || item.getId() != oldItem.getId() || !item.isUpdated()) {
                    writer.write(oldItem.toLineString());
                    writer.write(Constants.LINE_SEPARATOR);
                    return oldItem;
                }

         */
        public SynonymItem write(final SynonymItem oldItem) {
            try {
                if (item == null || item.getId() != oldItem.getId() || !item.isUpdated()) {
                    writer.write(oldItem.toLineString());
                    writer.write(Constants.LINE_SEPARATOR);
                    return oldItem;
                }

         */
        public ProtwordsItem write(final ProtwordsItem oldItem) {
            try {
                if (item == null || item.getId() != oldItem.getId() || !item.isUpdated()) {
                    writer.write(oldItem.toLineString());
                    writer.write(Constants.LINE_SEPARATOR);
                    return oldItem;
                }

         */
        public StopwordsItem write(final StopwordsItem oldItem) {
            try {
                if (item == null || item.getId() != oldItem.getId() || !item.isUpdated()) {
                    writer.write(oldItem.toLineString());
                    writer.write(Constants.LINE_SEPARATOR);
                    return oldItem;
                }