After having experimented with Go for the past few weeks, returning back to Java is a little bit annoying, especially when configuring web.xml and appengine-web.xml files. Golang has a clean, neat configuration file in app.yaml, and yet Java on App Engine has to deal with relatively heavyweight XML files.
For instance, this is the markup required to create an admin-only folder on J/GAE:
The markup alone is 2-3 times the size of the settings themselves! There needs to be a better way of handling this.