To deploy your app to App Engine, you will need to register a project to create your project ID, which will determine the URL for the app.
In the Cloud Platform Console, go to the Projects page and select or create a new project.
Note the project ID you created above, and enter it in src/main/webapp/WEB-INF/appengine-web.xml. You can also set the app version in this file.
Upload your application to Google App Engine by invoking the following command.
mvn appengine:update
Your app is now deployed and ready to serve traffic at http://<YOUR_PROJECT_ID>.appspot.com/.