1.Spring bean组件 ”默认为单例模式scope=“singleton， 运行JavaApplication容器启动时自动创建对象
scope=“prototype”为多例模式，请求条件下才创建对象
2beans组件 里面default-init-method初始化方法加载，范围比较大，当没有此方法时不会报错,default-destroy-method销毁方法，default-lazy-init=“true/false” 对象延时实例化
3.bean组件里面init-method初始化无此方法，会报错， destroy-method销毁方法，lazy-init=“true/false” 延时实例化
注意：
1.销毁方法对scope=“prototype”多例模式无效
2.AbstractApplicationContext可以关闭容器，可以调用close()方法，关闭容器，调用销毁方法
3.对象延时实例化对多例模式没有意义。
XML
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:p="http://www.springframework.org/schema/p" xmlns:util="http://www.springframework.org/schema/util" xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:cache="http://www.springframework.org/schema/cache" xsi:schemaLocation=" http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.1.xsd http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache-3.1.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd" default-init-method="initEmp" default-destroy-method="destroyEmp" default-lazy-init="true"> <bean id="emp" init-method="initEmp" destroy-method="destroyEmp" lazy-init="false" class="com.tracy.bean.Emp" scope="singleton" ></bean> </beans>
Test方法
//bean组件的默认方式
@Test
public void beanInitTest() {
AbstractApplicationContext appContext=new ClassPathXmlApplicationContext("com/tracy/xml/bean-init-destroy.xml");
ApplicationContext app=new ClassPathXmlApplicationContext("com/tracy/xml/bean-init-destroy.xml");
Emp emp=app.getBean("emp",Emp.class);
System.out.print(emp);
appContext.close();
}
通过构造完成初始bean属性，可以通过初始化完成
