Introducing Spring Framework

Chapter 3 ■ Applying Different Configurations
@Autowired
private DocumentDAO documentDAO;
public List findByType(Type documentType) {
List result = new ArrayList();
for(Document doc : listAll()){
if(doc.getType().getName().equals(documentType.getName()))
result.add(doc);
}
return result;
}
}
public List listAll() {
return Arrays.asList(documentDAO.getAll());
}
Listing 3-8 shows your new implementation of the SearchEngine, the AnnotatedSearchEngine class. As you can
see, you are using the @Service(“engine”) and the @Autowired annotations. The Spring Framework supports several
annotations (see Table 3-2) that are only markers or stereotypes like the @Service annotation. This annotation can
have a value, in this case “engine”, meaning that the container will create a bean with id: "engine" and it will point to
the AnnotatedSearchEngine class. This is the same as putting the following tag in an XML file:
Table 3-2. Stereotypes
Stereotype/Markers
@Component
@Repository
@Service
@Controller
Description
This is a marker, a generic stereotype that Spring will recognize as a Spring-managed
component.
This is a specialization of the @Component annotation and it fulfills the idea of the data access
object. Classes annotated with this annotation can be processed by other tools or even
aspects within the Spring container.
This is a specialization of the @Component annotation and it fulfills the idea of a service layer.
This is also a specialization of the @Component annotation and normally is used on a
web context.
Also, you used the @Autowired annotation. This annotation will tell the Spring container to actually create the
instance and assign it to the declared variable. This will be the same as the following configuration:
So, at the end, the AnnotatedSearchEngine class will be like having the following configuration all together:
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