Convert JSON to Map

Solution 1:

I hope you were joking about writing your own parser. :-)

For such a simple mapping, most tools from http://json.org (section java) would work. For one of them (Jackson https://github.com/FasterXML/jackson-databind/#5-minute-tutorial-streaming-parser-generator), you'd do:

Map<String,Object> result =
        new ObjectMapper().readValue(JSON_SOURCE, HashMap.class);

(where JSON_SOURCE is a File, input stream, reader, or json content String)

Solution 2:

Using the GSON library:

import com.google.gson.Gson;
import com.google.common.reflect.TypeToken;
import java.lang.reclect.Type;

Use the following code:

Type mapType = new TypeToken<Map<String, Map>>(){}.getType();  
Map<String, String[]> son = new Gson().fromJson(easyString, mapType);

Solution 3:

I like google gson library.
When you don't know structure of json. You can use

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

and then you can work with json. e.g. how to get "value1" from your gson:

String value1 = root.getAsJsonObject().get("data").getAsJsonObject().get("field1").getAsString();

Solution 4:

Use JSON lib E.g. http://www.json.org/java/

// Assume you have a Map<String, String> in JSONObject jdata
@SuppressWarnings("unchecked")
Iterator<String> nameItr = jdata.keys();
Map<String, String> outMap = new HashMap<String, String>();
while(nameItr.hasNext()) {
    String name = nameItr.next();
    outMap.put(name, jdata.getString(name));

}