Convert a JSON string to object in Java ME?

Question

Is there a way in Java/J2ME to convert a string, such as:

{name:\"MyNode\", width:200, height:100}

to an internal Object representation of

Answer 1

Use google GSON library for this

public static <T> T getObject(final String jsonString, final Class<T> objectClass) {  
    Gson gson = new Gson();  
    return gson.fromJson(jsonString, objectClass);  
}

http://iandjava.blogspot.in/2014/01/java-object-to-json-and-json-to-java.html

Answer 2

Like many stated already, A pretty simple way to do this using JSON.simple as below

import org.json.JSONObject;

String someJsonString = "{name:"MyNode", width:200, height:100}";
JSONObject jsonObj = new JSONObject(someJsonString);

And then use jsonObj to deal with JSON Object. e.g jsonObj.get("name");

As per the below link, JSON.simple is showing constant efficiency for both small and large JSON files

http://blog.takipi.com/the-ultimate-json-library-json-simple-vs-gson-vs-jackson-vs-json/

Answer 3

Jackson for big files, GSON for small files, and JSON.simple for handling both.

Answer 4

The simplest option is Jackson:

MyObject ob = new ObjectMapper().readValue(jsonString, MyObject.class);

There are other similarly simple to use libraries (Gson was already mentioned); but some choices are more laborious, like original org.json library, which requires you to create intermediate "JSONObject" even if you have no need for those.

Answer 5

You can do this easily with Google GSON.

Let's say you have a class called User with the fields user, width, and height and you want to convert the following json string to the User object.

{"name":"MyNode", "width":200, "height":100}

You can easily do so, without having to cast (keeping nimcap's comment in mind ;) ), with the following code:

Gson gson = new Gson(); 
final User user = gson.fromJson(jsonString, User.class);

Where jsonString is the above JSON String.

For more information, please look into https://code.google.com/p/google-gson/

Answer 6

GSON is a good option to convert java object to json object and vise versa.
It is a tool provided by google.

for converting json to java object use: fromJson(jsonObject,javaclassname.class)
for converting java object to json object use: toJson(javaObject)
and rest will be done automatically

For more information and for download