【Spring 系列】二、spring三种实例化bean的方式

• beans.xml中配置

  <!-- 三种实例化bean的方式 -->
  
   <!-- 1.使用类构造器实例化 -->
  <bean id="personService" class="com.liuyong666.service.impl.PersonServiceBean"></bean>
  
  <!-- 2.使用静态工厂方法实例化 -->
  <bean id="personService2" class="com.liuyong666.service.impl.PersonServiceBeanFactory" factory-method="createPersonServiceBean"></bean>
  
  <!-- 3.使用实例工厂方法实例化 -->
  <bean id="personServiceFactory" class="com.liuyong666.service.impl.PersonServiceBeanFactory"></bean>
  <bean id="personService3" factory-bean="personServiceFactory" factory-method="createPersonServiceBean2"></bean>
  

• PersonServiceBeanFactory类

  package com.liuyong666.service.impl;
  public class PersonServiceBeanFactory {
       
  	
  	public static PersonServiceBean createPersonServiceBean(){
       
  		return new PersonServiceBean();
  	}
  	
  	public PersonServiceBean createPersonServiceBean2(){
       
  		return new PersonServiceBean();
  	}
  }
  

• 测试类

  public class TestSpring {
   
  ​		/** ​ * 使用spring框架获取bean ​ */
  ​		@Test
  ​		public void getBeanBySpring(){
   
  ​			ApplicationContext context = new ClassPathXmlApplicationContext(new String[]{
   "beans.xml"});
  ​			PersonService bean = (PersonService) context.getBean("personService");
  ​			bean.save();
  ​		}
  ​		/** ​ * 使用静态工厂方法获取bean ​ */
  ​		@Test
  ​		public void getBeanByStaticFactory(){
   
  ​			ApplicationContext context = new ClassPathXmlApplicationContext(new String[]{
   "beans.xml"});
  ​			PersonService bean = (PersonService) context.getBean("personService2");
  ​			bean.save();
  ​		}
  ​		


  	/** * 使用实例工厂方法获取bean */
  	@Test
  	public void getBeanByInstantceFactory(){
   
  		ApplicationContext context = new ClassPathXmlApplicationContext(new String[]{
   "beans.xml"});
  		PersonService bean = (PersonService) context.getBean("personService3");
  		bean.save();
  	}
  
  }