1 singleton

spring 默认的模式，下面两种方式等价

<bean id="accountService" class="com.something.DefaultAccountService"/>

 <bean id="accountService" class="com.something.DefaultAccountService" scope="singleton"/>

每个spring容器只有一个实例

2prototype

每一个请求就容器就会创造一个实例

注意： Thus, although initialization lifecycle callback methods are called on all objects regardless of scope, in the case of prototypes, configured destruction lifecycle callbacks are not called.

bean的初始化方法会被调用，但是销毁时的disposal方法不会被调用，

　　

. Singleton Beans with Prototype-bean Dependencies

即使一个prototype的bean被注入到单例的bean中他依然是prototype的