- BeanPostProcessor接口：后置bean处理器，允许自定义修改新的bean实例，应用程序上下文可以在其bean定义中自动检测BeanPostProcessor类型的bean，并将它们应用于随后创建的任何bean。（例如：配置文件中注册了一个自定义BeanPostProcessor类型的bean，一个User类型的bean，应用程序上下文会在创建User实例之后对User应用BeanPostProcessor）。
- BeanFactoryPostProcessor接口：后置工厂处理器，允许自定义修改应用程序上下文的bean定义，调整bean属性值。应用程序上下文可以在其bean定义中自动检测BeanFactoryPostProcessor，并在创建任何非BeanFactoryPostProcessor类型bean之前应用它们（例如：配置文件中注册了一个自定义BeanFactoryPostProcessor类型的bean，一个User类型的bean，应用程序上下文会在创建User实例之前对User应用BeanFactoryPostProcessor）。
| 对比 | BeanFactoryPostProcessor | BeanPostProcessor |
| 回调时间 | Bean实例化完成之前 | Bean实例化完成之后 |
| 是否可修改bean定义信息 | 是 | 否 |
| 是否可修改bean实例信息 | 否 | 是 |
| 是否支持排序接口 | 是 | 是 |
| 方法级别 | ApplicationContext级别 | ApplicationContext级别 |
| 实现方式 | 注册自定义BeanFactoryPostProcessor，实现BeanFactoryAware接口 |
注册自定义BeanPostProcessor |
1. BeanPostProcessor
- bean
package com.lyc.cn.v2.day02.processor.bean; import com.lyc.cn.v2.day01.Dog; import org.springframework.beans.BeansException; import org.springframework.beans.factory.config.BeanPostProcessor; import org.springframework.core.Ordered; /** * 继承BeanPostProcessor接口并重写其方法 * @author: LiYanChao * @create: 2018-09-06 14:56 */ public class MyBeanPostProcessorOne implements BeanPostProcessor, Ordered { @Override public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException { System.out.println("BeanPostProcessor第" + getOrder() + "次被调动\n"); if (bean instanceof Dog) { ((Dog) bean).setName("强强"); } return bean; } @Override public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException { if (bean instanceof Dog) { ((Dog) bean).setAge(5); } return bean; } @Override public int getOrder() { return 1; } }
package com.lyc.cn.v2.day02.processor.bean; import org.springframework.beans.BeansException; import org.springframework.beans.factory.config.BeanPostProcessor; import org.springframework.core.Ordered; /** * 继承BeanPostProcessor接口并重写其方法 * @author: LiYanChao * @create: 2018-09-06 14:56 */ public class MyBeanPostProcessorTwo implements BeanPostProcessor, Ordered { @Override public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException { System.out.println("BeanPostProcessor第" + getOrder() + "次被调动"); return bean; } @Override public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException { return bean; } @Override public int getOrder() { return 2; } }
2. BeanFactoryPostProcessor
package com.lyc.cn.v2.day02.processor.factory; import org.springframework.beans.BeansException; import org.springframework.beans.MutablePropertyValues; import org.springframework.beans.factory.config.BeanDefinition; import org.springframework.beans.factory.config.BeanFactoryPostProcessor; import org.springframework.beans.factory.config.ConfigurableListableBeanFactory; import org.springframework.core.Ordered; public class MyBeanFactoryPostProcessorOne implements BeanFactoryPostProcessor, Ordered { /** * 修改dog的name属性值 * 修改dog的作用域 */ @Override public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException { System.out.println("BeanFactoryPostProcessor第" + getOrder() + "次被调动"); BeanDefinition bd = beanFactory.getBeanDefinition("dog"); if (null != bd) { System.out.println("dog属性值:" + bd.getPropertyValues().toString()); MutablePropertyValues pv = bd.getPropertyValues(); if (pv.contains("name")) { System.out.println("修改dog的name属性值为强强"); pv.addPropertyValue("name", "强强"); } System.out.println("修改dog的作用域为prototype\n"); bd.setScope(BeanDefinition.SCOPE_PROTOTYPE); } } @Override public int getOrder() { return 0; } }
package com.lyc.cn.v2.day02.processor.factory; import org.springframework.beans.BeansException; import org.springframework.beans.factory.config.BeanFactoryPostProcessor; import org.springframework.beans.factory.config.ConfigurableListableBeanFactory; import org.springframework.core.Ordered; public class MyBeanFactoryPostProcessorTwo implements BeanFactoryPostProcessor, Ordered { @Override public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException { System.out.println("BeanFactoryPostProcessor第" + getOrder() + "次被调动"); } @Override public int getOrder() { return 1; } }
- xml
<?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:p="http://www.springframework.org/schema/p" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd" profile="dev"> <bean id="dog" class="com.lyc.cn.v2.day01.Dog"> <!-- 指定构造器参数 index对应构造器中参数的位置 --> <!-- 也可以通过指定参数类型，指定参数名称来注入属性--> <constructor-arg index="0" value="小明"/> <constructor-arg index="1" value="3"/> </bean> <!-- =====beanPostProcessor配置begin =====--> <bean id="myBeanPostProcessorOne" class="com.lyc.cn.v2.day02.processor.bean.MyBeanPostProcessorOne"/> <bean id="myBeanPostProcessorTwo" class="com.lyc.cn.v2.day02.processor.bean.MyBeanPostProcessorTwo"/> <!-- =====beanPostProcessor配置end =====--> <!-- =====beanFactoryPostProcessor配置begin =====--> <!--注册第一个后置工厂处理器--> <bean id="myBeanFactoryPostProcessorOne" class="com.lyc.cn.v2.day02.processor.factory.MyBeanFactoryPostProcessorOne"/> <!--注册第二个后置工厂处理器--> <bean id="myBeanFactoryPostProcessorTwo" class="com.lyc.cn.v2.day02.processor.factory.MyBeanFactoryPostProcessorTwo"/> <!-- =====beanFactoryPostProcessor配置end =====--> </beans>
- 测试
package com.lyc.cn.v2.day02; import com.lyc.cn.v2.day01.Dog; import org.junit.After; import org.junit.Before; import org.junit.Test; import org.springframework.beans.factory.xml.XmlBeanFactory; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.core.io.ClassPathResource; /** * @author: LiYanChao * @create: 2018-09-07 23:40 */ public class MyTest { private XmlBeanFactory xmlBeanFactory; @Before public void initXmlBeanFactory() { System.setProperty("spring.profiles.active", "dev"); System.out.println("\n========测试方法开始=======\n"); xmlBeanFactory = new XmlBeanFactory(new ClassPathResource("v2/day01.xml")); } @After public void after() { System.out.println("\n========测试方法结束=======\n"); } @Test public void test1() { // 测试BeanPostProcessor ApplicationContext applicationContext = new ClassPathXmlApplicationContext("v2/day02.xml"); Dog dog = applicationContext.getBean("dog", Dog.class); dog.sayHello(); } @Test public void test2() { // 测试BeanFactoryPostProcessor ApplicationContext applicationContext = new ClassPathXmlApplicationContext("v2/day02.xml"); Dog dog = applicationContext.getBean("dog", Dog.class); dog.sayHello(); } }
- 结果
为了不影响测试结果，需要将BeanPostProcessor和BeanFactoryPostProcessor分开测试，测试test1时将test2的xml配置注释掉，反之亦然。
test1-->
========测试方法开始======= BeanPostProcessor第1次被调动 BeanPostProcessor第2次被调动 大家好, 我叫强强, 我今年5岁了 ========测试方法结束=======
test2-->
========测试方法开始======= BeanFactoryPostProcessor第0次被调动 dog属性值:PropertyValues: length=0 修改dog的作用域为prototype BeanFactoryPostProcessor第1次被调动 大家好, 我叫小明, 我今年3岁了 ========测试方法结束=======
