import java.util.Optional;

class Scratch {
    public static void main(String[] args) {
        checkAmount();
        checkPrice();
    }

    private static Optional<ValidationException> checkPrice() {
        Optional<ValidationException> optionalError = Optional.of(new ValidationException(ValidationException.NULL_FIELD, "Field %s is null"));

        if (optionalError.isPresent()) {
            ValidationException exception = optionalError.get();
            exception.enhance(PutOrderValidationCodePair.PRICE_FIELD);
            return optionalError;
        }
        return Optional.empty();
    }

    private static Optional<ValidationException> checkAmount() {
        Optional<ValidationException> optionalError = Optional.of(new ValidationException(ValidationException.NULL_FIELD, "%s is greater that 1000"));

        if (optionalError.isPresent()) {
            ValidationException exception = optionalError.get();
            exception.enhance(PutOrderValidationCodePair.AMOUNT_FIELD);
            return optionalError;
        }
        return Optional.empty();
    }
}

class ValidationException extends IllegalArgumentException {

    public static int NULL_FIELD = 0;
    public static int IS_GREATER = 1;
    public static int IS_LOWER = 2;

    protected int code;
    protected String formatText;

    protected ValidationException(int code, String formatText) {
        this.formatText = formatText;
        this.code = code;
    }

    public void enhance(ValidationCodePair codePair) {
        code += codePair.getCode();
        formatText = String.format(formatText, codePair.getFieldName());
    }

    public int getCode() {
        return this.code;
    }

    @Override
    public String getMessage() {
        return formatText;
    }
}

interface ValidationCodePair {

    int getCode();

    String getFieldName();

}

enum PutOrderValidationCodePair implements ValidationCodePair {

    AMOUNT_FIELD(10, "Amount"),
    PRICE_FIELD(20, "Price");

    private final int code;
    private final String fieldName;

    private PutOrderValidationCodePair(int code, String fieldName) {
        this.code = code;
        this.fieldName = fieldName;
    }

    @Override
    public int getCode() {
        return code;
    }

    @Override
    public String getFieldName() {
        return fieldName;
    }

}