code: public ExchangeRate getExchangeRate(CurrencyUnit base, CurrencyUnit term){
          Objects.requireNonNull(base, "Base Currency is null");
          Objects.requireNonNull(term, "Term Currency is null");
          return getExchangeRate(ConversionQueryBuilder.of().setBaseCurrency(base).setTermCurrency(term).build());
      }
docs: Access a {@link javax.money.convert.ExchangeRate} using the given currencies. The
  {@link javax.money.convert.ExchangeRate} may be, depending on the data provider, eal-time or
  deferred. This method should return the rate that is <i>currently</i>
  valid.
  
  @param base base {@link javax.money.CurrencyUnit}, not {@code null}
  @param term term {@link javax.money.CurrencyUnit}, not {@code null}
  @throws javax.money.convert.CurrencyConversionException If no such rate is available.