Check duplicate rows in View object ADF

    /**Method to check for duplicate rows
     * @param fileNm
     * @return
     */
    public String checkDuplicateRows(String fileNm) {
        ViewObject fileVo = this.getFileViewObject();
        Row duplFile[] = fileVo.getFilteredRows("FileName", fileNm);
        if (duplFile.length > 0) {
            return "Duplicate_Row_Exists";
        } else {
            return "No_Duplicate_Exists";
        }
    }

Other ways could be @ http://adfknowhow.blogspot.com/2015/01/how-to-filter-rows-in-vo.html