Introducing Spring Framework

Spring Stereotypes
Chapter 3 ■ Applying Different Configurations
Spring sterotypes are simply markers that help the Spring container to identify them as Spring-managed components.
These markers can be used for external processing tools or can be used as a reference for pointcuts in an aspectoriented
programming context. Nowadays in the Spring community, in many projects, the use of these stereotypes
helps not only to understand the code by making it more readable but also by identifying the structure and the
architectural layers. The most used stereotypes (by the Spring community and of course in your Spring application My
Documents) are described in Table 3-2.
Using the Java Bean Configuration
The Spring Framework version 3.0 adopted a new way to configure the Spring container, using a new Java bean
configuration class. This began as a separate project, but the Spring Framework team included it in version 3.0 as a
part of its core. Nowadays it is one of the most preferable ways to configure the container, because it helps to get a
clear picture of the relationship between classes and it shows how it interacts between them. And, in some cases it
even helps to avoid all the clutter of using XML files.
Now let’s see the following Java configuration class. Listing 3-11 is the equivalent of your XML configuration file
(see Listing 3-6). Every bean definition in your XML corresponds to the @Bean annotation placed into the method.
Listing 3-11. MyDocumentsContext.java
package com.apress.isf.spring.config;
import java.util.HashMap;
import java.util.Map;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.apress.isf.java.model.Document;
import com.apress.isf.java.model.Type;
import com.apress.isf.java.service.SearchEngine;
import com.apress.isf.spring.data.DocumentDAO;
import com.apress.isf.spring.data.DocumentRepository;
import com.apress.isf.spring.service.ServiceSearchEngine;
@Configuration
public class MyDocumentsContext {
private Map documents = new HashMap();
private Map types = new HashMap();
@Bean
public Type webType(){
return getTypeFromMap("web");
}
@Bean
public SearchEngine engine(){
ServiceSearchEngine engine = new ServiceSearchEngine();
engine.setDocumentDAO(documentDAO());
return engine;
}
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