Spring、实例化Bean的三种方法

1、使用类构造器进行实例化

<bean id="personIService" class="cn.server.impl.PersonServiceImpl" />

测试代码：

@Test
	public void test() {
		ApplicationContext ac = new ClassPathXmlApplicationContext("beans.xml");
		PersonIService personIService=(PersonIService)ac.getBean("personIService");
		personIService.helloSpring();
	}

2、使用静态工厂实例化

public class BeanFactory {
	public static PersonServiceImpl createPersonServiceImpl(){
		return new PersonServiceImpl();
	}
}

<bean id="personIService2" class="cn.BeanFactory" factory-method="createPersonServiceImpl" />

测试代码：

	@Test
	public void test3() {
		ApplicationContext ac = new ClassPathXmlApplicationContext("beans.xml");
		PersonIService personIService=(PersonIService)ac.getBean("personIService2");
		personIService.helloSpring();
	}

3、使用实例化工厂实例化

public class BeanFactory {
	public PersonServiceImpl createPersonServiceImpl2(){
		return new PersonServiceImpl();
	}
}

	<bean id="beanFactory" class="cn.BeanFactory"/>
	<bean id="personIService3" factory-bean="beanFactory"  factory-method="createPersonServiceImpl2" />

测试代码：

	@Test
	public void test4() {
		ApplicationContext ac = new ClassPathXmlApplicationContext("beans.xml");
		PersonIService personIService=(PersonIService)ac.getBean("personIService3");
		personIService.helloSpring();
	}