Convert JSONArray to arrayList

Question

I'm trying to convert a JSONArray which looks like this :

{"output":["name":"Name3","URI":"Value3"},{"name":"Name5","URI":"Value5"},{"name":"Name4","URI":"Value4"}]}

Into an arrayList so for example the output of Arr[0][0] will be Name3

I have tried this solution:

if (outputs!= null) { 
    int len = outputs.length();
    for (int j=0;j<len;j++){ 
        list.add(outputs.get(j).toString());
    } 
} 
for (String str : list) {               
    System.out.println("Item is: " + str);              
}

But I get the full row : {"name":"Name3","URI":"Value3"}

How can I get each object of my JSONArray?

Solution 1

Aazelix, your Json output seem to be missing opening array bracket. Its correct form is listed below:

{"output":[{"name":"Name3","URI":"Value3"},{"name":"Name5","URI":"Value5"},{"name":"Name4","URI":"Value4"}]}

As for the conversion to POJO

List<MyObj> list = new ArrayList<>();
if (outputs!= null) { 
  int len = outputs.length();
  for (int i=0; i<len; i++) { 
    JSONObject o = (JSONObject) outputs.get(i);
    list.add(new MyObj(o.getString('name'), o.getString('URL')));
  } 
} 
System.out.println("There is " + list.size() + " objects.");
public static final class MyObj {
  final String name;
  final String url;
  public MyObj(String name, String url) {
     this.name = name;
     this.url  = url;
  }
}

Solution 2

It is not specified, which JSON parser do you use, so I suppose you can choose right now and I'll suggest using Gson as such.

The better solution for deserializing such a structures is creating a special class for each structure, for example:

public class NameURIPair {
    private String name;
    private String URI;
    // getters
}

Then your JSON can be deserialized into a class, which holds the resulting List in it:

public class Data {
    private List<NameURIPair> output;
    // getter
}
// ...
Data data = new Gson(stringData, Data.class);

Since you've requested the other way, you still can get just the parsed JSON into JsonElement with JsonParser

JsonElement root = new JsonParser().parse(stringData);

Although I won't give you the full solution not to appreciate this kind of solutions :-)

Comments

[Dmitry Ginzburg]

o.name; o.URL. Really?

[Dmitry Ginzburg]

second poing: OP had URI, not URL

[MaxZoom]

I did not compile nor run the code so it may need some improvements.