<caption> bean的作用域 </caption>
作用域 描述
singleton 单例模式,IOC容器仅生成和管理一个bean实例,是默认的作用域
prototype 多例模式,IOC容器将为每次请求创建一个新的实例
request 在一次HTTP请求中返回一个bean实例,不同的HTTP请求返回不同的bean实例
session 在一个HTTP session中,容器返回同一个bean实例
application 为每个ServletContext对象创建一个实例,即同一个应用共享同一个bean实例
websocket 为每个WebSocket对象创建一个bean实例

示例------prototype作用域

<?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="constructorInstance" class="instance.BeanClass"  scope="prototype">
        <!-- scope作用域,singleton单例模式,singleton是scope的默认模式 -->
        <!-- scope作用域,prototype多例模式,ioc容器将为每次请求创建一个新的实例 -->
    </bean>
    
    <!-- 静态工厂实例化bean  -->
	<bean id="staticFacoryInstance" class="instance.BeanStaticFactory" factory-method="createInstance">
	
	</bean>
	
	<!-- 配置工厂 -->
    <bean id="myFactory" class="instance.BeanInstanceFactory">
    </bean>
    <!-- 实例工厂实例化bean  -->
    <bean id="instanceFacoryInstance" factory-bean="myFactory" factory-method="createBeanClassInstance">
    </bean>
    
</beans>
package test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import instance.BeanClass;

public class TestInstance {
	public static void main(String[] args) {
		ApplicationContext appCon = new ClassPathXmlApplicationContext("applicationContext.xml");
		
		BeanClass b1 = (BeanClass)appCon.getBean("constructorInstance");
		System.out.println(b1+b1.message);
		
		BeanClass b6 = (BeanClass)appCon.getBean("constructorInstance");
		System.out.println(b6+b6.message);
		
		//测试静态工厂实例化bean
		BeanClass b2 =(BeanClass)appCon.getBean("staticFacoryInstance");
		System.out.println(b2+b2.message);
		
		//测试实例广场实例化bean
		BeanClass b3 =(BeanClass)appCon.getBean("instanceFacoryInstance");
		System.out.println(b3+b3.message);
	}
}