code: public void appendWorkSheetColumns(WorkSheet worksheet) throws Exception {
  
  		ArrayList<String> newColumns = worksheet.getColumns();
  
  		this.addColumns(newColumns, "");
  		ArrayList<String> rows = this.getRows();
  		for (String row : rows) {
  			for (String col : newColumns) {
  				if (worksheet.isValidRow(row)) {
  					String value = worksheet.getCell(row, col);
  					this.addCell(row, col, value);
  				}
  
  			}
  		}
  
  
  
  	}
docs: Add columns from a second worksheet to be joined by common row. If the
  appended worksheet doesn't contain a row in the master worksheet then
  default value of "" is used. Rows in the appended worksheet not found in
  the master worksheet are not added.
  
  @param worksheet
  @throws Exception