Framework based DI Code Example 
I highly discourage anybody from using hard coded strings in-line.
The example in the last section of the page would be better if we added an static class to it that contains the strings:
//static class provided by the framework or written by the user to indicate which dependencies are available
public static class MyAvailableServices{
    public static final string CarBuilderService = "CarBuilderService";
    public static final string VanBuilderService = "VanBuilderService";
}

public class MyApplication {
    public static void main(String[] args) {
        Service service = (Service)DependencyManager.get(MyAvailableServices.CarBuilderService);
        Car car = (Car)service.getService(Car.class);
        car.setPedalPressure(5);
        float speed = car.getSpeedInMPH();
    }
}