final String url = GWT.getHostPageBaseURL() + "api/version/softwareUpdates"; //$NON-NLS-1$
RequestBuilder requestBuilder = new RequestBuilder( RequestBuilder.GET, url );
requestBuilder.setHeader( "If-Modified-Since", "01 Jan 1970 00:00:00 GMT" );
requestBuilder.setHeader( "accept", "text/plain" );
try {
requestBuilder.sendRequest( null, new RequestCallback() {
public void onError( Request request, Throwable exception ) {
MessageDialogBox dialogBox =
new MessageDialogBox(
Messages.getString( "softwareUpdates" ), Messages.getString( "noUpdatesAvailable" ), false, false, true ); //$NON-NLS-1$ //$NON-NLS-2$