code: public void addCell(String row, String col, String value) throws Exception {
  		HeaderInfo rowIndex = rowLookup.get(row);
  		HeaderInfo colIndex = columnLookup.get(col);
  		if (rowIndex == null) {
  			throw new Exception("Row " + row + " not found in worksheet");
  		}
  		if (colIndex == null) {
  			throw new Exception("Column " + col + " not found in worksheet");
  		}
  
  
  		data[rowIndex.getIndex()][colIndex.getIndex()] = new CompactCharSequence(value);
  	}
docs: Add data to a cell
  
  @param row
  @param col
  @param value
  @throws Exception