Spring相关的API-ApplicationContext

1.ClassPathXmlApplicationContext
它是从类的根路径下加载配置文件推荐使用这种

public class UserController {
    public static void main(String[] args) {
        ApplicationContext context=new ClassPathXmlApplicationContext("applicationContext.xml");
        UserService service = (UserService) context.getBean("userService");
        service.sava();

    }
}

**2.**FileSystemXmlApplicationContext（用的不多）
它是从磁盘路径上加载配置文件，配置文件可以在磁盘的任意位置

public class UserController {
    public static void main(String[] args) {
        ApplicationContext context=new FileSystemXmlApplicationContext("D:\\spring\\src\\main\\resources\\applicationContext.xml");
        UserService service = (UserService) context.getBean("userService");
        service.sava();

    }
}

3.AnnotationConfigApplicationContext
当使用注解配置容器对象时，需要使用此类来创建spring容器，它来读取注解

public class UserController {
    public static void main(String[] args) {
        ApplicationContext context=new AnnotationConfigApplicationContext(SpringConfiguration.class);
        UserService service = (UserService) context.getBean("userService");
        service.sava();
    }
}