How to use

DefaultAmountFormatter

in

com.ning.billing.util

@Override
public BigDecimal getRate() {
  return round(BigDecimal.ZERO);
}

@Override
public BigDecimal getPaidAmount() {
  return round(Objects.firstNonNull(invoice.getPaidAmount(), BigDecimal.ZERO));
}

  @Override
  public BigDecimal getRefundedAmount() {
    return round(Objects.firstNonNull(invoice.getRefundedAmount(), BigDecimal.ZERO));
  }
}

  @Override
  public String getFormattedBalanceOfUnpaidInvoices() {
    return round(Objects.firstNonNull(getBalanceOfUnpaidInvoices(), BigDecimal.ZERO)).toString();
  }
}

@Override
public BigDecimal getChargedAmount() {
  return round(Objects.firstNonNull(invoice.getChargedAmount(), BigDecimal.ZERO));
}

@Override
public BigDecimal getBalance() {
  return round(Objects.firstNonNull(invoice.getBalance(), BigDecimal.ZERO));
}

@Override
public BigDecimal getCreditedAmount() {
  return round(Objects.firstNonNull(invoice.getCreditedAmount(), BigDecimal.ZERO));
}

@Override
public BigDecimal getOriginalChargedAmount() {
  return round(Objects.firstNonNull(invoice.getOriginalChargedAmount(), BigDecimal.ZERO));
}

@Override
public BigDecimal getAmount() {
  return round(Objects.firstNonNull(item.getAmount(), BigDecimal.ZERO));
}