SpringBean实例化的基本流程源码剖析

<?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="userDao" class="com.itheima.dao.impl.UserDaoImpl"></bean>
    <bean id="userService" class="com.itheima.service.impl.UserServiceImpl"></bean>
</beans>

package com.itheima.test;
import com.alibaba.druid.pool.DruidDataSource;
import com.itheima.dao.impl.UserDaoImpl;
import com.itheima.service.UserService;
import com.mysql.jdbc.Connection;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import javax.xml.bind.annotation.XmlAccessOrder;
import java.io.IOException;
import java.io.InputStream;
import java.sql.DriverManager;
public class BeanFactoryTest {
    public static void main(String[] args) throws Exception {
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext_beanfac.xml");
        UserService userService = (UserService) applicationContext.getBean("userService");
    }
}

<?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="userDao" class="com.itheima.dao.impl.UserDaoImpl"></bean>
    <bean id="userService" class="com.itheima.service.impl.UserServiceImpl">
        <property name="userDao" ref="userDao"/>
    </bean>
</beans>