Spring教程（1）：IoC获取Bean

1.导入spring坐标

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>5.2.10.RELEASE</version>
</dependency>

2.新建 BookDao 及实现类

BookDao

public interface BookDao {
    public void save();
}

BookDaoImpl

public class BookDaoImpl implements BookDao {
    @Override
    public void save() {
        System.out.println("book dao -- save");

    }
}

2.新建 applicationContext.xml 配置文件

<?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="bookDao" class="com.badianboke.dao.impl.BookDaoImpl"></bean>
    <bean id="bookService" class="com.badianboke.service.impl.BookServiceImpl"></bean>

</beans>

3.使用

public static void main(String[] args){
    ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
    BookDao bookDao = (BookDao) ctx.getBean("bookDao");
    bookDao.save();
}