[
  {
    "amount": 15.1999999999999999,
    "currency": "USD"

  }
]

public static double parseDouble(String s) throws NumberFormatException {
    // [JACKSON-486]: avoid some nasty float representations... but should it be MIN_NORMAL or MIN_VALUE?
    /* as per [JACKSON-827], let's use MIN_VALUE as it is available on all JDKs; normalized
     * only in JDK 1.6. In practice, should not really matter.
     */
    if (NASTY_SMALL_DOUBLE.equals(s)) {
        return Double.MIN_VALUE;
    }
    return Double.parseDouble(s);
}

public NumberType getNumberType() throws IOException
    {
        if (_numTypesValid == NR_UNKNOWN) {
            _parseNumericValue(NR_UNKNOWN); // will also check event type
        }
        if (_currToken == JsonToken.VALUE_NUMBER_INT) {
            if ((_numTypesValid & NR_INT) != 0) {
                return NumberType.INT;
            }
            if ((_numTypesValid & NR_LONG) != 0) {
                return NumberType.LONG;
            }
            return NumberType.BIG_INTEGER;
        }

        /* And then floating point types. Here optimal type
         * needs to be big decimal, to avoid losing any data?
         * However... using BD is slow, so let's allow returning
         * double as type if no explicit call has been made to access
         * data as BD?
         */
        if ((_numTypesValid & NR_BIGDECIMAL) != 0) {
            return NumberType.BIG_DECIMAL;
        }
        return NumberType.DOUBLE;
    }

@JsonDeserialize(using=MyBigDecimalDeserializer.class)
 private BigDecimal amount;

public class MyBigDecimalDeserializer extends JsonDeserializer<BigDecimal> {

    private NumberDeserializers.BigDecimalDeserializer delegate = NumberDeserializers.BigDecimalDeserializer.instance;

    @Override
    public BigDecimal deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException, JsonProcessingException {
        BigDecimal bd = delegate.deserialize(jp, ctxt);
      // bd = bd.setScale(2, RoundingMode.HALF_UP);
        return bd;
    }
}

SimpleModule testModule = new SimpleModule("MyBigDecimalDeserializer", new Version(1, 0, 0, "beta"))
            .addDeserializer(BigDecimal.class, new MyBigDecimalDeserializer());
        mapper.registerModule(testModule);