spring 生命周期

1.car类

package com.hxzy.cycle;

public class Car {

private String brand;

public Car() {

System.out.println("构造器运行");

}

public void setBrand(String brand) {

System.out.println("set方法调用");

this.brand = brand;

}

public void init() {

System.out.println("init方法");

}

public void destory() {

System.out.println("destory方法");

}

@Override

public String toString() {

return "Car [brand=" + brand + "]";

}

}

2.后置处理器类

package com.hxzy.cycle;

import org.springframework.beans.BeansException;

import org.springframework.beans.factory.config.BeanPostProcessor;

public class MyBeanPostProcess implements BeanPostProcessor {

//在init-method方法之后被调用

// bean: bean 实例本身

// beanName: IOC容器配置的bean的名字

// 返回值：是实际上返回给用户的那个bean，可以在重新的方法中修改返回值。

@Override

public Object postProcessAfterInitialization(Object bean, String beanName)

throws BeansException {

System.out.println("在初始化方法之后 后置处理器 : " + bean + ", " + beanName);

//偷梁换柱，添加此处代码后，输出中直接将朗逸换为途观

Car car = new Car();

car.setBrand("途观");

return car;

// return bean;

}

//在init-method方法之前被调用

@Override

public Object postProcessBeforeInitialization(Object bean, String beanName)

throws BeansException {

System.out.println("在初始化方法之前 后置处理器 : "+ bean + ", " + beanName);

if ("car".equals(beanName)) {

System.out.println("啥也不做");

}

return bean;

}

}

3.bean配置类

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="car" class="com.hxzy.cycle.Car"

init-method="init"

destroy-method="destory">

<property name="brand" value="朗逸"> </property>

</bean>

<!-- 配置bean的后置处理器 -->

<bean class="com.hxzy.cycle.MyBeanPostProcess"></bean>

</beans>

4.测试类

package com.hxzy.cycle;

import org.springframework.context.support.AbstractApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class TestBeanCycle {

public static void main(String[] args) {

ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("cycle.xml");

Car car = (Car) ctx.getBean("car");

System.out.println(car);

ctx.close();

}

}

运行效果

信息: Loading XML bean definitions from class path resource [cycle.xml]

构造器运行

set方法调用

在初始化方法之前 后置处理器 : Car [brand=朗逸], car

啥也不做

init方法

在初始化方法之后 后置处理器 : Car [brand=朗逸], car

构造器运行

set方法调用

Car [brand=途观]

十月 08, 2015 3:36:05 下午 org.springframework.context.support.AbstractApplicationContext doClose

信息: Closing org.springframework.context.support.ClassPathXmlApplicationContext@117ae12: startup date [Thu Oct 08 15:36:05 CST 2015]; root of context hierarchy

destory方法