/** Key for file user in metadata */
    public static final String FS_FILE_USER = "fsFileUser";

    /** Key for file groups in metadata */
    public static final String FS_FILE_GROUPS = "fsFileGroups";

    /** Character encoding for files */
    protected String charset = Constants.UTF_8;

    /** Helper for managing content length limits */
    @Resource
    protected ContentLengthHelper contentLengthHelper;