Injecting DBDriver/Logger, AOP in Dart

In order to have GUI component, each component should not have a direct dependency to a specific driver. For instance, in the sample app, AppController has reference to CouchDBClientDao, but we if want to allow other DB driver later, that should not be directly defined in the component class.
This issue can be handled in Java as annotation based injection. JPA entity factory etc can be injected through annotation.

In order to support this, there will be a few approaches.
One approach is to simulate Java's approach. but it requires a special run time lib support for actual injection. So these are actually not within an ordinal programming control, and create some opaqueness for the code behavior, so I actually do not like this idea much.

The other approach is to delegate this injection job to code(programmer) itself. Anyway entry program needs to do some environment setting job normally, adding a task to inject code to appropriate library is not much big deal. and it will allows programmer 100% control over what is happening in program execution time.

then how can we find the location of the class(instance) to inject db driver.
sometimes that component are in deeply nested from top level component node.

That time we may use query feature defined at Component class.
This approach is similar to query in Dart.
To inject to annotated filed for an instance, whenever instance is created, this injection code must be applied. So instance level injection is a bit costly operation.

Or the other hand, static class level injection can be done only once, so this should be efficient.
for instance, dbdriver, logger can be injected to a  static filed.