Displaying parsed JSON data into a pane (GWT)

Question

I am parsing JSON data and currently it can display in a dialog box. But I'm having trouble displaying it in the Pane. I'm pretty new to GWT and would appreciate any guidance. I provided the appropriate methods below.

private void jsonPane(String jsonText, final FlowPanel jsonSource) {
       jsonText = jsonText.replaceAll(">", ">");
       Label json = new HTML("<pre>" + jsonText + "</pre>", false);
       parseData();
       jsonSource.add(json);
    }

// Parsing the JSON Data
    private void parseData() {
        RequestBuilder requestBuilder = new RequestBuilder(RequestBuilder.GET, "/jsongwtexample/greet");
        try {
            requestBuilder.sendRequest(null, new RequestCallback() {

                @Override
                public void onResponseReceived(Request request, Response response) {
                    JSONValue jsonValue = JSONParser.parseStrict(response.getText());

                    JSONObject weatherObject = jsonValue.isObject();
                    JSONArray jsonArray = weatherObject.get("Weather").isArray();

                    StringBuilder builder = new StringBuilder("** TODAYS WEATHER** \n");
                    builder.append(jsonArray.get(0).isObject().get("Town").isString().stringValue()).append(" ");
                    builder.append(jsonArray.get(0).isObject().get("Weather").isString().stringValue());
                    builder.append("\n");

                    builder.toString();

                }

                @Override
                public void onError(Request request, Throwable exception) {
                    Window.alert("Some error occurred: " + exception.getMessage());

                }
            });
        } catch (RequestException e) {
            e.printStackTrace();
        }
    }

Answer 1

I would use a plain label, rather than an HTML one, to prevent malicious HTML-injection.

private Label label = new Label();

You can style the label to display just like a <pre>:

public void onModuleLoad() {
    RootPanel.get().add(label);
    label.getElement().getStyle().setWhiteSpace(WhiteSpace.PRE);
}

Inside your parseData() method you need to set the label's text:

@Override
public void onResponseReceived(Request request, Response response) {
    ...

    label.setText(builder.toString());
}