How to use

javax.money.convert.CurrencyConversionException

constructor

@Override
public ExchangeRate getExchangeRate(ConversionQuery conversionQuery) {
  for (ExchangeRateProvider prov : this.providers) {
    try {
      if (prov.isAvailable(conversionQuery)) {
        ExchangeRate rate = prov.getExchangeRate(conversionQuery);
        if (Objects.nonNull(rate)) {
          return rate;
        }
      }
    } catch (Exception e) {
      Logger.getLogger(getClass().getName()).log(Level.WARNING,
          "Rate Provider did not return data though at check before data was flagged as available," +
              " provider=" + prov.getContext().getProviderName() + ", query=" + conversionQuery);
    }
  }
  throw new CurrencyConversionException(conversionQuery.getBaseCurrency(), conversionQuery.getCurrency(), null,
      "All delegate prov iders failed to deliver rate, providers=" + this.providers +
          ", query=" + conversionQuery);
}

@Override
public ExchangeRate getExchangeRate(ConversionQuery conversionQuery) {
  CurrencyUnitPair pair = new CurrencyUnitPair(conversionQuery.getBaseCurrency(), conversionQuery.getCurrency());
  MonitoredCurrency monitoredCurrency = monitoredCurrencies.get(pair);
  if (monitoredCurrency == null) {
    throw new CurrencyConversionException(pair.getBase(),
        pair.getTarget(),
        null,
        "Pair not found.");
  }
  ExchangeRate rate = null;
  try {
    rate = buildExchangeRate(pair, monitoredCurrency.getTicker());
  } catch (TimeoutException e) {
    throw new MonetaryException("Timeout loading exchange rate", e);
  } catch (InterruptedException e) {
    Thread.currentThread().interrupt(); // Restore interruption flag
  }
  return rate;
}

/**
 * Method that converts the source {@link MonetaryAmount} to an
 * {@link MonetaryAmount} based on the {@link ExchangeRate} of this
 * conversion.
 * @param amount The source amount
 * @return The converted amount, never null.
 * @throws CurrencyConversionException if conversion failed, or the required data is not available.
 * @see #getExchangeRate(MonetaryAmount)
 */
@Override
public MonetaryAmount apply(MonetaryAmount amount) {
  if (termCurrency.equals(Objects.requireNonNull(amount).getCurrency())) {
    return amount;
  }
  ExchangeRate rate = getExchangeRate(amount);
  if (Objects.isNull(rate) || !amount.getCurrency().equals(rate.getBaseCurrency())) {
    throw new CurrencyConversionException(amount.getCurrency(),
        this.termCurrency, null);
  }
  NumberValue factor = rate.getFactor();
  factor = roundFactor(amount, factor);
  Integer scale = rate.getContext().get(KEY_SCALE, Integer.class);
  if(Objects.isNull(scale) || scale < 0) {
    return amount.multiply(factor).getFactory().setCurrency(rate.getCurrency()).create();
  } else {
    return amount.multiply(factor).getFactory().setCurrency(rate.getCurrency()).create().with(MonetaryOperators.rounding(scale));
  }
}

private ExchangeRate createExchangeRate(ConversionQuery query,
                    ExchangeRateBuilder builder, ExchangeRate sourceRate,
                    ExchangeRate target) {
  if (areBothBaseCurrencies(query)) {
    builder.setFactor(DefaultNumberValue.ONE);
    return builder.build();
  } else if (BASE_CURRENCY_CODE.equals(query.getCurrency().getCurrencyCode())) {
    if (Objects.isNull(sourceRate)) {
      return null;
    }
    return reverse(sourceRate);
  } else if (BASE_CURRENCY_CODE.equals(query.getBaseCurrency()
      .getCurrencyCode())) {
    return target;
  } else {
    ExchangeRate rate1 = getExchangeRate(
        query.toBuilder().setTermCurrency(Monetary.getCurrency(BASE_CURRENCY_CODE)).build());
    ExchangeRate rate2 = getExchangeRate(
        query.toBuilder().setBaseCurrency(Monetary.getCurrency(BASE_CURRENCY_CODE))
            .setTermCurrency(query.getCurrency()).build());
    if (Objects.nonNull(rate1) && Objects.nonNull(rate2)) {
      builder.setFactor(multiply(rate1.getFactor(), rate2.getFactor()));
      builder.setRateChain(rate1, rate2);
      return builder.build();
    }
    throw new CurrencyConversionException(query.getBaseCurrency(),
        query.getCurrency(), sourceRate.getContext());
  }
}