public boolean copyDocIndex(final String fromIndex, final String toIndex, final boolean waitForCompletion) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final String source = fessConfig.getIndexReindexBody()//
                .replace("__SOURCE_INDEX__", fromIndex)//
                .replace("__SIZE__", fessConfig.getIndexReindexSize())//
                .replace("__DEST_INDEX__", toIndex)//

     * comment: Request body template for reindex operations.
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getIndexReindexBody();

    /**
     * Get the value for the key 'index.reindex.requests_per_second'. <br>
     * The value is, e.g. adaptive <br>
     * comment: Requests per second for reindex operations ("adaptive" for auto).