Understanding Spring @Autowired usage

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I am reading the spring 3.0.x reference documentation to understand Spring Autowired annotation:

3.9.2 @Autowired and @Inject

I am not able to understand the below examples. Do we need to do something in the XML for it to work?

EXAMPLE 1

public class SimpleMovieLister {

    private MovieFinder movieFinder;

    @Autowired
    public void setMovieFinder(MovieFinder movieFinder) {
        this.movieFinder = movieFinder;
    }

    // ...
}

EXAMPLE 2 

public class MovieRecommender {

    private MovieCatalog movieCatalog;

    private CustomerPreferenceDao customerPreferenceDao;

    @Autowired
    public void prepare(MovieCatalog movieCatalog,
                    CustomerPreferenceDao customerPreferenceDao) {
        this.movieCatalog = movieCatalog;
        this.customerPreferenceDao = customerPreferenceDao;
    }

    // ...
}

How can the two classes be autowired implementing the same interface and using the same class?

Example: 

class Red implements Color
class Blue implements Color

class myMainClass{
    @Autowired 
    private Color color;

    draw(){
        color.design(); 
    } 
}

Which design method will be called? How do I make sure the design method of Red class will be called and not Blue?

3 Answers
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