Spring 学习

小鱼儿 2024-03-24 17:08 11阅读 0赞

断点：

spring-ioc.xml

<?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="person" class="com.ybb.springmydemo.dto.Person">
    
        </bean>
    
    
    
    </beans>

Spring基础容器BeanFactory：

import com.ybb.springmydemo.dto.Person;
    import org.junit.jupiter.api.Test;
    import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
    import org.springframework.beans.factory.xml.XmlBeanFactory;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.core.io.ClassPathResource;
    import org.springframework.core.io.Resource;
    
    @SpringBootTest
    class SpringMyDemoApplicationTests {
    
        @Test
        void contextLoads() throws Exception {
            /** spring基础容器 */
            Resource resource = new ClassPathResource("spring/spring-ioc.xml");
            XmlBeanFactory beanFactory = new XmlBeanFactory(resource);
            /** BeanDefinition注册流程的入口 */
            XmlBeanDefinitionReader reader = new XmlBeanDefinitionReader(beanFactory);
            reader.loadBeanDefinitions(resource);
    
            /** getBean的时候才会创建Bean实例对象 */
            Person person = (Person) beanFactory.getBean("person");
            System.out.println(person);
        }
    
    }

Spring高级容器ApplicationContext

import org.junit.jupiter.api.Test;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    
    @SpringBootTest
    class SpringMyDemoApplicationTests {
    
        @Test
        void contextLoads() throws Exception {
            /** 创建IOC容器，并进行初始化, 此时Bean实例已经被创建完成 */
            ApplicationContext context = new ClassPathXmlApplicationContext("spring/spring-ioc.xml");
            System.out.println("=================================");
    
            /** 获取Bean的实例，并验证Bean的实例是否是单例模式的 */
            Person person = (Person)context.getBean("person");
            Person person2 = (Person)context.getBean("person");
    
            System.out.println("person:"+person);
            System.out.println("person2:"+person2);
    
        }
    
    }