Gson with dynamic name (Android)

Question

I'm a beginner in java/Android and I try to parse JSON with Gson.

I'm having some difficulty with the files part. From what I've read I should use MapHash but I'm not sure how to use it in this code

Here my Main class

InputStream source = retrieveStream(url);
Gson gson = new Gson();
Reader reader = new InputStreamReader(source);
SearchResponse response = gson.fromJson(reader, SearchResponse.class);

The class that do the parsing

public class SearchResponse {

    public List<Podcast> podcasts; 

    class Podcast {

        @SerializedName("files")
        private List<File> files;

        @SerializedName("format")
        private String format;

        @SerializedName("title")
        private String title;

    class File {
        private String ValueX;
        private String URLX;
        }
    }
}

json structure

{
"podcasts": [
    {
    "files": [
        {"NameA": "ValueA"},
        {"NameB": "ValueB"},
        {"...": "..."}
    ],
    "format": "STRING",
    "title": "STRING"
    }
    ]
}

Thanks for your help

here's an edited file of the structure of the JSon I try to parse http://jsontest.web44.net/noauth.json

You can parse a JSON even without using Gson. What do you want to get from the JSONObject ? — Shobhit Puri, May 25 '13 at 22:02
You alreay have the JSON object with you, which might be a response from somewhere? — Shobhit Puri, May 25 '13 at 22:10

MikO · Accepted Answer · 2013-05-25T23:52:43.523

5

In your File class you have 2 attributes: ValueX and URLX. But in your JSON you have 2 fields NameA and NameB...

Names in JSON response and your class must match, otherwise you won't get any value...

Apart from that, your class structure looks good, and your code for deseralizing looks good as well... I don't think you need any HashMap...

EDIT: Taking into account your comment, you could use a HashMap. You could change your Podcast class using:

@SerializedName("files")
private List<Map<String,String>> files;

And you should get it parsed correctly.

You have to use a List because you have a JSON array (surrounded by [ ]), and then you can use the Map to allow different field names.

Note that you have to delete your File class...

edited May 25 '13 at 23:52

answered May 25 '13 at 23:11

MikO

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but the name and value are random. I've edited my post to reflect that. I've put a file to show how the json is structured http://jsontest.web44.net/noauth.json – Keven May 25 '13 at 23:19
thanks I've also found my answer on http://stackoverflow.com/questions/7651953/gson-parsing-dynamic-json-field except mine was like you said really a list – Keven May 26 '13 at 00:02

Gson with dynamic name (Android)

1 Answers1