Sunday, October 24, 2010

Vaadin on Google App Engine part 2: Creating the Web Application Project

To create a Vaadin web application on Google App Engine, in Eclipse IDE click File > New > Project... and create a new Vaadin project.

Make sure you choose Google App Engine as the Deployment configuration.

Then enable Google App Engine nature in your project:

  1. Right click your project > Properties...
  2. Go to Google > App Engine
  3. Check the Use Google App Engine checkbox
  4. Pick the Google App Engine SDK that you use or click Configure SDKs... if necessary

To ensure that JDO enhancement by DataNucleus access platform works correctly, do the following workaround:
  1. Right click your project > Properties...
  2. Go to Java Build Path
  3. Remove Web App Libraries
  4. Click Add JARs..., and select the war/WEB-INF/lib/vaadin-x.x.x.jar
Now your Vaadin application should run fine. You can also start adding JDO entities with proper DataNucleus JDO code enhancement.