Introduction to Spring - Spring Enterprise Recipes: A Problem Solution Approach - page 21

How It Works
To ask Spring to auto-wire the bean properties with @Autowired or @Resource , you have to register an
AutowiredAnnotationBeanPostProcessor instance in the IoC container. If you are using a bean factory,
you have to register this bean post processor through the API. Otherwise, you can just declare an
instance of it in your application context.

<bean class="org.springframework.beans.factory.annotation. ➥

AutowiredAnnotationBeanPostProcessor" />

Or you can simply include the <context:annotation-config> element in your bean configuration
file, and an AutowiredAnnotationBeanPostProcessor instance will automatically get registered.

<beans xmlns=" http://www.springframework.org/schema/beans"
xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance"
xmlns:context=" http://www.springframework.org/schema/context"
xsi:schemaLocation=" http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">

<context:annotation-config />
...
</beans>

Auto-Wiring a Single Bean of Compatible Type
The @Autowired annotation can be applied to a particular property for Spring to auto-wire it. As an
example, you can annotate the setter method of the prefixGenerator property with @Autowired . Then
Spring will attempt to wire a bean whose type is compatible with PrefixGenerator .

package com.apress.springenterpriserecipes.sequence;

import org.springframework.beans.factory.annotation.Autowired;

public class SequenceGenerator {
...
@Autowired
public void setPrefixGenerator(PrefixGenerator prefixGenerator) {
this.prefixGenerator = prefixGenerator;
}
}

If you have a bean whose type is compatible with PrefixGenerator defined in the IoC container, it
will be set to the prefixGenerator property automatically.