@Component注解

一时失言乱红尘 2023-07-17 15:34 35阅读 0赞

package org.springframework.stereotype;
    
    import java.lang.annotation.Documented;
    import java.lang.annotation.ElementType;
    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;
    import java.lang.annotation.Target;
    
    /** * Indicates that an annotated class is a "component". * Such classes are considered as candidates for auto-detection * when using annotation-based configuration and classpath scanning. * * <p>Other class-level annotations may be considered as identifying * a component as well, typically a special kind of component: * e.g. the {@link Repository @Repository} annotation or AspectJ's * {@link org.aspectj.lang.annotation.Aspect @Aspect} annotation. * * @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
    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 */
    	String value() default "";
    
    }

`@Component`注解：

*  该注解使用在类上面，表示这个类是一个`component`
 *  当使用基于注解的配置和类路径扫描时，这种类就是自动检测的候选类
 *  其他类级别的注释也可以视为标识`component`
 *  通常是一种特殊的组件,比如`@Repository`和`AspectJ`的`@Aspect`注解  
    ![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTI5MzQzMjU_size_16_color_FFFFFF_t_70]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTI5MzQzMjU_size_16_color_FFFFFF_t_70]: /images/20230528/74fe43ddde064379ab61871d47e40d53.png