code: @SuppressWarnings("unchecked")
  	private <T> T toType(String cell,DataType  dataType)
  	{
  		
  		switch(dataType)
  		{
  			case Long: return cell != null && cell.length() > 0 ? (T)Long.valueOf(cell) : (T)Long.valueOf(-1); 
  			default: return (T)cell;
  		}
  	}
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