configuration and bean

In spring, besides XML config, we also can use java config to do our spring.

Here is an example of XML and Java Config which is the same:

<beans>
    <bean id="course" class="demo.Course">
        <property name="module" ref="module"/>
      </bean>

    <bean id="module" class="demo.Module">
        <property name="assignment" ref="assignment"/>
      </bean>

    <bean id="assignment" class="demo.Assignment" />
</beans>

##

@Configuration
public class AppContext {
    @Bean
    public Course course() {
        Course course = new Course();
        course.setModule(module());
        return course;
    }

    @Bean
    public Module module() {
        Module module = new Module();
        module.setAssignment(assignment());
        return module;
    }

    @Bean
    public Assignment assignment() {
        return new Assignment();
    }
}