- 可以使用@Autowired注解那些众所周知的解析依赖性接口，比如：BeanFactory,ApplicationContext,Environment,ResourceLoader,ApplicationEventPublisher,MessageSource
package com.mypackage; import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext; public class MovieRecommender { @Autowired
private ApplicationContext context; public MovieRecommender(){
} //...
}
- 可以通过添加注解给需要该类型的数组的字段和方法，以提供ApplicationContext中的所有特定类型的bean
private Set<MovieCatalog> movieCatalogs; @Autowired
public void setMovieCatalogs(Set<MovieCatalog> movieCatalogs) {
this.movieCatalogs = movieCatalogs;
}
- 可以用于装配key为String的Map
private Map<String , MovieCatalog> movieCatalog; @Autowired
public void setMovieCatalog(Map<String, MovieCatalog> movieCatalog) {
this.movieCatalog = movieCatalog;
}
- 如果希望数组有序，可以让bean实现org.springframework.core.Ordered接口或使用的@Order注解
- @Autowired是由Spring BeanPostProcessor处理的，所以不能在自己的BeanPostProcessor或BeanFactoryPostProcessor类型应用这些注解，这些类型必须通过XML或者Spring的@Bean注解加载
数组及Map的自动注入——例子：
先定义一个BeanInterface接口
package com.multibean;
public interface BeanInterface {
}
在定义两个实现类
package com.multibean; import org.springframework.stereotype.Component; @Component
public class BeanInterfaceImpl implements BeanInterface { }
package com.multibean; import org.springframework.stereotype.Component; @Component
public class BeanInterface2Impl implements BeanInterface{ }
定义BeanInvoker实现数组和Map
package com.multibean; import java.util.*; import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component; @Component
public class BeanInvoker { @Autowired
private List<BeanInterface> list; @Autowired
private Map<String,BeanInterface> map; public void say(){
if(null != list){
System.out.println("list...");
for(BeanInterface bean:list){
System.out.println(bean.getClass().getName());
}
}else{
System.out.println("List<BeanInterface> list is null.");
} if(null != map && 0 != map.size()){
System.out.println("map...");
for(Map.Entry<String,BeanInterface> entry:map.entrySet()){
System.out.println(entry.getKey()+"-----"+entry.getValue().getClass().getName());
}
}else{
System.out.println("Map<String,BeanInterface> map is null.");
}
} }
XML配置：
<?xml version="1.0" encoding="UTF-8"?>
<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-4.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.1.xsd"> <context:component-scan base-package="com.multibean">
</context:component-scan>
</beans>
单元测试：
package com.multibean; import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; public class UnitTest { @Test
public void test(){
ApplicationContext context = new ClassPathXmlApplicationContext("classpath:spring-beansnnotation.xml");
BeanInvoker beanInvoker = (BeanInvoker)context.getBean("beanInvoker");
beanInvoker.say();
}
}
结果：
七月 06, 2015 10:46:41 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@32482417: startup date [Mon Jul 06 22:46:41 CST 2015]; root of context hierarchy
七月 06, 2015 10:46:41 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-beansnnotation.xml]
list...
com.multibean.BeanInterface2Impl
com.multibean.BeanInterfaceImpl
map...
beanInterface2Impl-----com.multibean.BeanInterface2Impl
beanInterfaceImpl-----com.multibean.BeanInterfaceImpl
@Order注解----例子：
改造一下两个实现类，加上@Order注解
package com.multibean; import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component; @Order(value = 1)
@Component
public class BeanInterfaceImpl implements BeanInterface { }
package com.multibean; import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component; @Order(value = 2)
@Component
public class BeanInterface2Impl implements BeanInterface{ }
测试同上
结果：
七月 06, 2015 10:58:58 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@1e397bcb: startup date [Mon Jul 06 22:58:58 CST 2015]; root of context hierarchy
七月 06, 2015 10:58:58 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-beansnnotation.xml]
list...
com.multibean.BeanInterfaceImpl
com.multibean.BeanInterface2Impl
map...
beanInterface2Impl-----com.multibean.BeanInterface2Impl
beanInterfaceImpl-----com.multibean.BeanInterfaceImpl
PS：@Order只针对数组，对于map无效