Given a json string, you could convert it to either JSONObject(str) or JSONArray(str). For example, This json response is from weather forecaset server:
http://api.openweathermap.org/data/2.5/forecast/daily?zip=545%2Ctw&mode=json&units=metric&cnt=7&appid=aa032e548c67daa9cd1bc64eec737960
The response json format is like this:
If you want to get the first max temperature value: 17.06:
JSONObject weather = new JSONObject(weatherJsonStr);
JSONArray daysWeather = weather.getJSONArray("list");
JSONObject dayWeather = daysWeather.getJSONObject(0);
JSONObject dayTemperature = dayWeather.getJSONObject("temp");
int maxTemp = dayTemperature.getDouble("max");
Note that there may has a JSONException when the json tring is invalid, you need to add try-catch for this.
public class WooliesCrawler {
static class Product{
private int mStockCode;
private String mName;
private float mPrice;
private float mWasPrice;
private float mCupPrice;
private String mCupMeasure;
private boolean mIsAvailable;
public Product(String name, int stockCode, float price, float wasPrice, float cupPrice, String cupMeasure, boolean isAvailable) {
mStockCode = stockCode;
mName = name;
mPrice = price;
mWasPrice = wasPrice;
mCupPrice = cupPrice;
mCupMeasure = cupMeasure;
mIsAvailable = isAvailable;
}
@Override
public String toString() {
return String.format("%s %s %s %s %s", mStockCode, mName, mWasPrice, mPrice, mIsAvailable);
}
}
public static void downloadProducts(final Context context, final int pageNumber){
RequestQueue queue = Volley.newRequestQueue(context);
int groupId = 1018;
final int pageSize = 100;
String urlFormat = "https://www.woolworths.com.au/apis/ui/Product/Specials/half-price?GroupID=%s&pageNumber=%s&pageSize=%s";
String url = String.format(urlFormat, groupId, pageNumber, pageSize);
StringRequest request = new StringRequest(Request.Method.GET, url,
new Response.Listener<String>() {
@Override
public void onResponse(String response) {
List<Product> productList = new ArrayList<>();
String text = response;
try {
JSONObject root = new JSONObject(text);
JSONArray items = root.getJSONArray("Items");
for (int i = 0; i < items.length(); i++) {
JSONObject itemList = (JSONObject) items.get(i);
JSONArray products = itemList.getJSONArray("Products");
JSONObject productJson = (JSONObject) products.get(0);
String name = productJson.getString("Name");
int stockCode = productJson.getInt("Stockcode");
float price = (float) productJson.getDouble("Price");
float wasPrice = (float) productJson.getDouble("WasPrice");
String cupMeasure = productJson.getString("CupMeasure");
float cupPrice = (float) productJson.getDouble("CupPrice");
boolean isAvailable = productJson.getBoolean("IsAvailable");
Product product = new Product(name, stockCode, price, wasPrice, cupPrice, cupMeasure, isAvailable);
productList.add(product);
Timber.d(product.toString());
}
if(items.length() == pageSize){
downloadProducts(context, pageNumber+1);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Timber.e(error);
}
});
queue.add(request);
}
}