你只理解了一部分。您必须根据需要定制bean，并通知Spring容器在需要时管理它，方法是使用Martin Fowler创造的通常称为IoC(控制反转)的方法，也称为依赖注入(DI)。

您以某种方式连接bean，这样您就不必关心实例化或计算bean上的任何依赖项。这就是众所周知的好莱坞原则。

谷歌是最好的工具，除了在这个问题中你会被淹没的链接之外，还可以探索更多关于这个问题的内容。：）

For Spring, all objects are beans! The fundamental step in the Spring Framework is to define your objects as beans. Beans are nothing but object instances that would be created by the spring framework by looking at their class definitions. These definitions basically form the configuration metadata. The framework then creates a plan for which objects need to be instantiated, which dependencies need to be set and injected, the scope of the newly created instance, etc., based on this configuration metadata. The metadata can be supplied in a simple XML file, just like in the first chapter. Alternatively, one could provide the metadata as Annotation or Java Configuration.

书:Just Spring

Spring beans are classes. Instead of instantiating a class (using new), you get an instance as a bean cast to your class type from the application context, where the bean is what you configured in the application context configuration. This way, the whole application maintains singleton-scope instance throughout the application. All beans are initialized following their configuration order right after the application context is instantiated. Even if you don't get any beans in your application, all beans instances are already created the moment after you created the application context.

Spring beans are just object instances that are managed by the Spring IOC container. Spring IOC container carry the Bag of Bean.Bean creation,maintain and deletion are the responsibilities of Spring Container. We can put the bean in to Spring by Wiring and Auto Wiring. Wiring mean we manually configure it into the XML file. Auto Wiring mean we put the annotations in the Java file then Spring automatically scan the root-context where java configuration file, make it and put into the bag of Spring.

Spring的XML配置由bean组成，而bean基本上是类。它们只是我们在ApplicationContext中使用的pojo。定义bean可以看作是替换关键字new。所以无论你在应用程序中使用关键字new，比如:

MyRepository myRepository =new MyRepository ();

当你使用关键字new时你可以删除配置并将其放入XML文件中。 所以我们将像这样编码:

<bean name="myRepository " 
      class="com.demo.repository.MyRepository " />

现在我们可以简单地使用Setter注入/构造函数注入。我正在使用Setter注入。

public class MyServiceImpl implements MyService {
    private MyRepository myRepository;
    public void setMyRepository(MyRepository myRepository)
        {
    this.myRepository = myRepository ;
        }
public List<Customer> findAll() {
        return myRepository.findAll();
    }
}

春天有IoC容器，里面装着一袋豆子;创建、维护和删除是Spring Container的职责。 我们可以通过布线和自动布线将bean放到Spring中。 “连线”意味着我们手动将其配置到XML文件中，“自动连线”意味着我们将注释放入Java文件中，然后Spring自动扫描Java配置文件所在的根上下文，将其制作并放入Spring的包中。

这里是详细的URI，您可以从中获得有关bean的更多信息