@Component

源码

/**
 * Indicates that an annotated class is a "component".
  表名注解类是一个 “组件”
 * Such classes are considered as candidates for auto-detection
 * when using annotation-based configuration and classpath scanning.
  当基于注解配置和类路径扫描的时候，这些类被认为是自动探测的候选类 (candidates)
 * <p>Other class-level annotations may be considered as identifying
 * a component as well, typically a special kind of component:
  其他登记的注解也可能被认为是识别一个组件，典型的类如一种特殊的组件：
 * e.g. the {@link Repository @Repository} annotation or AspectJ's
 * {@link org.aspectj.lang.annotation.Aspect @Aspect} annotation.
  @Repository 注解或者 AspectJ 的 @Aspect 注解
 *
 * @author Mark Fisher
 * @since 2.5
 * @see Repository
 * @see Service
 * @see Controller
 * @see org.springframework.context.annotation.ClassPathBeanDefinitionScanner
 */
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Indexed
public @interface Component {

  /**
   * The value may indicate a suggestion for a logical component name,
   * to be turned into a Spring bean in case of an autodetected component.
   * @return the suggested component name, if any (or empty String otherwise)
   */
  String value() default "";

}