String INDEX_ADMIN_ARRAY_FIELDS = "index.admin.array.fields";

    /** The key of the configuration. e.g. expires,created,timestamp,last_modified */
    String INDEX_ADMIN_DATE_FIELDS = "index.admin.date.fields";

    /** The key of the configuration. e.g.  */
    String INDEX_ADMIN_INTEGER_FIELDS = "index.admin.integer.fields";

    /** The key of the configuration. e.g. content_length,favorite_count,click_count */