HTTP Calls

If your GWT application needs to communicate with a server, but you can't use Java servlets on the backend, you'll need to use direct HTTP instead of GWT's RPC framework. GWT contains a number of HTTP client classes that simplify making custom HTTP requests to your server and optionally processing a JSON- or XML-formatted response.

Specifics

Making HTTP requests Use the RequestBuilder and other classes in the com.google.gwt.http.client package to build and send HTTP requests.

Working with JSON Parse and create JSON encoded data using the JSON client types.

Working with XML Parse and create XML documents using GWT's XML processing types.