public List<Balance> loadV1() {
        Optional<String> jsonBodyOptional = executeWalletRequest();
        return jsonBodyOptional.map(jsonBody -> {
            BalanceResponse balanceResponse =
                    JsonUtils.toObj(jsonBody, BalanceResponse.class);
            List<Balance> result = Optional.ofNullable(balanceResponse.getAmounts())
                    .map(amounts -> amounts.stream()
                            .map(amount -> buildUnifiedBalanceRow(balanceResponse, amount))
                            .collect(Collectors.<Balance>toList()))
                    .orElse(Lists.newArrayList());
            return result;
        }).orElse(Lists.newArrayList());
}

public List<Balance> loadV2() {
    String jsonBody =  executeWalletRequest();
    if (StringUtil.isEmpty(jsonBody)) {
        return Collections.emptyList();
    }
    BalanceResponse balanceResponse = JsonUtils.toObj(jsonBody, BalanceResponse.class)
    if (balanceResponse == null || balanceResponse.getAmounts() == null) {
        return Collections.emptyList();
    }
    List<Balance> result = new ArrayList<>();
    for (Amount amount : balanceResponse.getAmounts()) {
        result.add(buildUnifiedBalanceRow(balanceResponse, amount));
    }
    return result;
}