- BeanPostProcessor接口：后置bean處理器，允許自定義修改新的bean實例甸昏，應(yīng)用程序上下文可以在其bean定義中自動檢測BeanPostProcessor類型的bean撇贺，并將它們應(yīng)用于隨后創(chuàng)建的任何bean谦疾。（例如：配置文件中注冊了一個自定義BeanPostProcessor類型的bean纷闺，一個User類型的bean刨秆，應(yīng)用程序上下文會在創(chuàng)建User實例之后對User應(yīng)用BeanPostProcessor）凳谦。
- BeanFactoryPostProcessor接口：后置工廠處理器，允許自定義修改應(yīng)用程序上下文的bean定義衡未，調(diào)整bean屬性值尸执。應(yīng)用程序上下文可以在其bean定義中自動檢測BeanFactoryPostProcessor，并在創(chuàng)建任何非BeanFactoryPostProcessor類型bean之前應(yīng)用它們（例如：配置文件中注冊了一個自定義BeanFactoryPostProcessor類型的bean缓醋，一個User類型的bean如失，應(yīng)用程序上下文會在創(chuàng)建User實例之前對User應(yīng)用BeanFactoryPostProcessor）。
| 對比 | BeanFactoryPostProcessor | BeanPostProcessor |
|---|---|---|
| 回調(diào)時間 | Bean實例化完成之前 | Bean實例化完成之后 |
| 是否可修改bean定義信息 | 是 | 否 |
| 是否可修改bean實例信息 | 否 | 是 |
| 是否支持排序接口 | 是 | 是 |
| 方法級別 | ApplicationContext級別 | ApplicationContext級別 |
| 實現(xiàn)方式 | 注冊自定義BeanPostProcessor | 注冊自定義BeanFactoryPostProcessor送粱，實現(xiàn)BeanFactoryAware接口 |
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;
/**
* 繼承BeanPostProcessor接口并重寫其方法
* @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() + "次被調(diào)動\n");
if (bean instanceof Dog) {
((Dog) bean).setName("強強");
}
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;
/**
* 繼承BeanPostProcessor接口并重寫其方法
* @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() + "次被調(diào)動");
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屬性值
* 修改dog的作用域
*/
@Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
System.out.println("BeanFactoryPostProcessor第" + getOrder() + "次被調(diào)動");
BeanDefinition bd = beanFactory.getBeanDefinition("dog");
if (null != bd) {
System.out.println("dog屬性值:" + bd.getPropertyValues().toString());
MutablePropertyValues pv = bd.getPropertyValues();
if (pv.contains("name")) {
System.out.println("修改dog的name屬性值為強強");
pv.addPropertyValue("name", "強強");
}
System.out.println("修改dog的作用域為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() + "次被調(diào)動");
}
@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">
<!-- 指定構(gòu)造器參數(shù) index對應(yīng)構(gòu)造器中參數(shù)的位置 -->
<!-- 也可以通過指定參數(shù)類型褪贵，指定參數(shù)名稱來注入屬性-->
<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 =====-->
<!--注冊第一個后置工廠處理器-->
<bean id="myBeanFactoryPostProcessorOne" class="com.lyc.cn.v2.day02.processor.factory.MyBeanFactoryPostProcessorOne"/>
<!--注冊第二個后置工廠處理器-->
<bean id="myBeanFactoryPostProcessorTwo" class="com.lyc.cn.v2.day02.processor.factory.MyBeanFactoryPostProcessorTwo"/>
<!-- =====beanFactoryPostProcessor配置end =====-->
</beans>
- 測試
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========測試方法開始=======\n");
xmlBeanFactory = new XmlBeanFactory(new ClassPathResource("v2/day01.xml"));
}
@After
public void after() {
System.out.println("\n========測試方法結(jié)束=======\n");
}
@Test
public void test1() {
// 測試BeanPostProcessor
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("v2/day02.xml");
Dog dog = applicationContext.getBean("dog", Dog.class);
dog.sayHello();
}
@Test
public void test2() {
// 測試BeanFactoryPostProcessor
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("v2/day02.xml");
Dog dog = applicationContext.getBean("dog", Dog.class);
dog.sayHello();
}
}
- 結(jié)果
為了不影響測試結(jié)果，需要將BeanPostProcessor和BeanFactoryPostProcessor分開測試抗俄，測試test1時將test2的xml配置注釋掉脆丁，反之亦然。
test1-->
========測試方法開始=======
BeanPostProcessor第1次被調(diào)動
BeanPostProcessor第2次被調(diào)動
大家好, 我叫強強, 我今年5歲了
========測試方法結(jié)束=======
test2-->
========測試方法開始=======
BeanFactoryPostProcessor第0次被調(diào)動
dog屬性值:PropertyValues: length=0
修改dog的作用域為prototype
BeanFactoryPostProcessor第1次被調(diào)動
大家好, 我叫小明, 我今年3歲了
========測試方法結(jié)束=======
