Default Postgres add-ons for Java
Change effective on 23 August 2016
Heroku’s support for Java now creates a free Heroku Postgres add-on during the first deployment of an application if the buildpack detects a dependency on the Postgres JDBC driver or pgjdbc-ng driver in the repository’s
pom.xml. This differs from earlier behavior, which created a Heroku Postgres add-on for all Java apps.
If the buildpack does not create the add-on for an application, you can create one manually by running:
$ heroku addons:create heroku-postgresql --app sushi
For more information, see the Dev Center documentation for Java.