code: public int getIndex(String headerName) throws IOException {
  		checkClosed();
  
  		Object indexValue = headersHolder.IndexByName.get(headerName);
  
  		if (indexValue != null) {
  			return ((Integer) indexValue).intValue();
  		} else {
  			return -1;
  		}
  	}
docs: Gets the corresponding column index for a given column header name.
  
  @param headerName
  The header name of the column.
  @return The column index for the given column header name.&nbsp;Returns
  -1 if not found.
  @exception IOException
  Thrown if this object has already been closed.