Working with JSON


The GWTedition contains a JSON extension that provides a org.restlet.client.ext.json.JsonRepresentation class that you can leverage to either parse a JSON representation received or to serialize a JSON value.

Prior to leverage this extension, ensure to update your module.gwt.xml configuration file with the following instruction:

<inherits name="org.restlet.JSON" />

Here is a sample code taken from the example application. The JsonRepresentation gives access to the underlying JSONValue after the representation has been parsed.

ClientResource r = new ClientResource("/test");

// Set the callback object invoked when the response is received.
r.setOnResponse(new Uniform() {
    public void handle(Request request, Response response) {
        // Get the representation as an JsonRepresentation
        JsonRepresentation rep = new JsonRepresentation(response.getEntity());

        // Displays the properties and values.
        try {
            JSONObject object = rep.getValue().isObject();
            if (object != null) {
                for (String key : object.keySet()) {
                    jsonRoot.addItem(key + ":" + object.get(key));
        } catch (IOException e) {

// Indicates the client preferences and let the server handle
// the best representation with content negotiation.