Spring1 Bean实例化

1. Bean实例化的方法
a. 普通方法

public class PersonServiceBean implements PersonService {public void save(){System.out.println("我是save()方法");}}

<bean id="personService" class="cn.itcast.service.impl.PersonServiceBean"></bean>

@Test public void instanceSpring(){ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");PersonService personService = (PersonService)ctx.getBean("personService");personService.save();}

b. 静态工厂方法

public class PersonServiceBeanFactory {public static PersonServiceBean createPersonServiceBean(){return new PersonServiceBean();}}

<bean id="personService2" class="cn.itcast.service.impl.PersonServiceBeanFactory"           factory-method="createPersonServiceBean"/>

@Test public void instanceSpring(){ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");PersonService personService = (PersonService)ctx.getBean("personService2");personService.save();}

c. 工厂方法

public class PersonServiceBeanFactory {public PersonServiceBean createPersonServiceBean2(){return new PersonServiceBean();}}

<bean id="personServiceFactory" class="cn.itcast.service.impl.PersonServiceBeanFactory"/>          <bean id="personService3" factory-bean="personServiceFactory" factory-method="createPersonServiceBean2"/>

@Test public void instanceSpring(){ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");PersonService personService = (PersonService)ctx.getBean("personService3");personService.save();}