JSONObject and Streams/Lambda - json

Question

I'm trying to get more familiar with Java lambda, can do some streams and such but still a lot to learn.
Got this simple code using JSONObject and JSONArray (org.json.simple with this exact library and no other because Gson is too easy :P) is there a way to simplify the code with java lambda/streams? (I tried with no luck)
JSONArray jsonArray = (JSONArray) jsonObject.get("someData");
Iterator<JSONObject> iterator = jsonArray.iterator();
double total = 0;
while(iterator.hasNext()) {
JSONObject iteratedJson = iterator.next();
// iteratedJson.get("ip") = "101.99.99.101" example values
String ip = (String) iteratedJson.get("ip");
// Need only first octet
ip = ip.substring(0, ip.indexOf("."));
if (Integer.valueOf(ip) >= 1 && Integer.valueOf(ip) <= 100) {
// Another object inside the array object
JSONObject locationObject = (JSONObject) iteratedJson.get("location");
// Id is int but JSONObject don't let me parse int...
long locationId = (Long) locationObject.get("id");
if (locationId == 8) {
// iteratedJson.get("amount") = "$1,999.10" example values
Number number = NumberFormat.getCurrencyInstance(Locale.US).parse((String)iteratedJson.get("amount"));
// Don't need a lot of precission
total = total + number.doubleValue();
}
}
}

Answer 1

You can do like this:
first of all to extract data from JsonObject I've created a class. this class takes a JosonObject as an argument and extract its values as bellow.
class ExtractData {
Integer ip;
long id;
double amount;
public ExtractData(JSONObject jsonObject) {
this.ip = Integer.valueOf(jsonObject.get("ip").toString().split("\\.")[0]);
this.id = Long.parseLong(((JSONObject) jsonObject.get("location")).get("id").toString());
try {
this.amount = NumberFormat.getCurrencyInstance(Locale.US)
.parse((String) jsonObject.get("amount")).doubleValue();
} catch (ParseException e) {
this.amount = 0d;
}
}
// getter&setter
}
then you can use stream API to calculate the sum of the amount property.
jsonArray.stream()
.map(obj -> new ExtractData((JSONObject) obj))
.filter(predicate)
.mapToDouble(value -> ((ExtractData) value).getAmount())
.sum();
for simplifying I've extracted filter operation.
Predicate<ExtractData> predicate = extractData ->
extractData.getIp()>=1 && extractData.getIp()<=100 && extractData.getId() == 8;