Annotation indicating this method should be called when the application starts up.
If nothing else depends on this bean, then this bean will only work if the bean is explicitly bound.
Note: If this bean is provided by an @Provided method, then that method *must* be annotated with @Singleton,
otherwise it won't be detected.
The order in which it should be started, higher meaning later.
public abstract int order
The order in which it should be started, higher meaning later. While apps are free to use any ordering system
they wish, the following convention is recommended:
10 - Services that connect to resources and do not depend on other services, for example, database connections
20-80 - Services that depend on resources, but don't actually start the app doing its core functions
90 - Services that start the app doing its core functions, for example, listen on queues, listen for HTTP, start
The order, the least being started first, the greatest being started last