SpringIOC容器Bean的作用域及生命周期实例

@Test
    public void testCollection2() {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean2.xml");
        Book book = context.getBean("book", Book.class);
        Book book2 = context.getBean("book", Book.class);
        System.out.println(book);
        System.out.println(book2);
    }

com.pingguo.spring5.collectiontype.Book@4ae82894
com.pingguo.spring5.collectiontype.Book@4ae82894
Process finished with exit code 0

<bean id="book" class="com.pingguo.spring5.collectiontype.Book" scope="prototype">
        <property name="list" ref="bookList"></property>
    </bean>

com.pingguo.spring5.collectiontype.Book@543788f3
com.pingguo.spring5.collectiontype.Book@6d3af739
Process finished with exit code 0

package com.pingguo.spring5.bean;
public class Orders {
    public Orders() {
        System.out.println("第一步：执行无参构造方法创建 bean 的实例");
    }
    private String orderName;
    public void setOrderName(String orderName) {
        this.orderName = orderName;
        System.out.println("第二步：调用 set 方法设置属性值");
    }
    // 创建执行的初始化方法，需要在配置文件中配置调用
    public void initMethod() {
        System.out.println("第三步：执行初始化方法");
    }
    // 创建 bean 销毁方法，需要在配置文件中配置调用
    public void destroyMethod() {
        System.out.println("第五步：执行销毁的方法");
    }
}

<?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">
    <!--配置初始化方法、销毁方法-->
    <bean id="orders" class="com.pingguo.spring5.bean.Orders"
          init-method="initMethod"
          destroy-method="destroyMethod">
        <property name="orderName" value="苹果"></property>
    </bean>
</beans>

@Test
    public void test4() {
        ClassPathXmlApplicationContext context =
                new ClassPathXmlApplicationContext("bean4.xml");
        Orders orders = context.getBean("orders", Orders.class);
        System.out.println("第四步：获取创建的 bean 实例对象");
        System.out.println(orders);
        // 手动让 bean 实例销毁
        context.close();
    }

第一步：执行无参构造方法创建 bean 的实例
第二步：调用 set 方法设置属性值
第三步：执行初始化方法
第四步：获取创建的 bean 实例对象
com.pingguo.spring5.bean.Orders@43738a82
第五步：执行销毁的方法
Process finished with exit code 0

package com.pingguo.spring5.bean;
import org.springframework.beans.factory.config.BeanPostProcessor;
public class MyBeanPost implements BeanPostProcessor {
}

package com.pingguo.spring5.bean;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
public class MyBeanPost implements BeanPostProcessor {
    @Override
    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
        System.out.println("执行初始化之前的方法");
        return bean;
    }
    @Override
    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
        System.out.println("执行初始化之后的方法");
        return bean;
    }
}

<!--配置后置处理器-->
    <bean id="myBeanPost" class="com.pingguo.spring5.bean.MyBeanPost"></bean>