List<Field> fields = getFields();
fields.add(new DateField(Messages.CSVColumn_Date));
fields.add(new Field(Messages.CSVColumn_ISIN).setOptional(true));
fields.add(new Field(Messages.CSVColumn_TickerSymbol).setOptional(true));
fields.add(new Field(Messages.CSVColumn_WKN).setOptional(true));
fields.add(new AmountField(Messages.CSVColumn_Value));
fields.add(new AmountField(Messages.CSVColumn_Fees).setOptional(true));
fields.add(new AmountField(Messages.CSVColumn_Taxes).setOptional(true));
fields.add(new AmountField(Messages.CSVColumn_Shares));
fields.add(new EnumField<PortfolioTransaction.Type>(Messages.CSVColumn_Type,
PortfolioTransaction.Type.class).setOptional(true));
}