今天给大家分享一下Spring中@ComponentScan注解的用法。希望对您有所帮助！1、@ComponentScan注解的作用作用是定义包扫描规则，然后根据定义的规则找出哪些类需要自动组装到springbean容器中，然后交给spring进行统一管理。说明：所有标有@Controller、@Service、@Repository、@Component的类都可以被spring扫描到。2、@ComponentScan注解属性介绍2.1value指定要扫描的包路径2.2excludeFilters(排除规则)excludeFilters=Filter[]指定指定包扫描时根据规则排除的组件2.3includeFilters(包含规则)includeFilters=Filter[]指定扫描包时，根据规则指定要包含的组件。注意：必须设置useDefaultFilters=false（系统默认为true，需要手动设置）includeFilters包含过滤规则才能生效。2.4FilterType属性FilterType.ANNOTATION：根据注解过滤FilterType.ASSIGNABLE_TYPE：根据给定的类型指定具体的类，子类也会被扫描到FilterType.ASPECTJ：使用ASPECTJ表达式FilterType.REGEX：正则FilterType.CUSTOM：自定义ruleuseDefaultFilters:配置是否开启可以检测@Component,@Repository,@Service,@Controller注解的类，Java8语法可以指定多个@ComponentScan，Java83以下可以用@ComponentScans()配置多个规则,Example3.1各种过滤规则示例//includeFilters用法includeAnimal.class类可以被扫描，包括它的子类@ComponentScan(value="com.spring"includeFilters={@ComponentScan.Filter(type=FilterType.ASSIGNABLE_TYPE,classes={Animal.class})})//excludeFilters用法排除包含@Controller注解的类@ComponentScan(value="com.spring",excludeFilters={@ComponentScan.Filter(type=FilterType.ANNOTATION,classes={Controller.class}),})//ComponentScans用法@ComponentScans(value={@ComponentScan(value="com.spring",includeFilters={@ComponentScan.Filter（类型=FilterType.ANNOTATION,classes={Controller.class})},useDefaultFilters=false),@ComponentScan(value="com.spring",excludeFilters={@ComponentScan.Filter(type=FilterType.ANNOTATION,classes={Repository.class})})})*///@ComponentScan//Java8语法可以指定多个@ComponentScan，//@ComponentScans()可以在Java8以下配置多个规则@ComponentScan(value="com.spring",excludeFilters={@ComponentScan.Filter(type=FilterType.ANNOTATION,classes={Controller.class,Controller.class}),},includeFilters={@ComponentScan.Filter(type=FilterType.ANNOTATION,classes={Controller.class,Controller.class}),})3.2自定义过滤规则需要新建TestTypeFilter.javapackagecom.spring.config;importorg.springframework.core.io.Res来源；导入org.springframework.core.type.AnnotationMetadata；导入org.springframework.core.type.ClassMetadata；导入org.springframework.core.type.classreading.MetadataReader；导入org.springframework.core.type.classreading.MetadataReaderFactory；importorg.springframework.core.type.filter.TypeFilter;importjava.io.IOException;/***metadataReader读取当前正在扫描的类信息*metadataReaderFactory可以获取任何其他类的信息*/publicclassTestTypeFilterimplementsTypeFilter{publicbooleanmatch(MetadataReadermetadataReader,MetadataReaderFactorymetadataReaderFactory)throwsIOException{//获取当前类注解信息AnnotationMetadataannotationMetadata=metadataReader.getAnnotationMetadata();//获取当前正在扫描的类信息ClassMetadataclassMetadata=metadataReader.getClass/Metadata(/获取当前类资源信息（比如类的文件路径）Resourceresource=metadataReader.getResource();StringclassName=classMetadata.getClassName();System.out.println("类名："+cl驴名);如果（className.contains（“控制器”））{返回真；}else{返回错误；}}}3.3新建测试类TestComponentScan.javapackagecom.spring.test;importcom.spring.config.TestComponentScanConfig;importorg.springframework.context.annotation.AnnotationConfigApplicationContext;公共类TestComponentScan{publicstaticvoidmain(String[]args){AnnotationConfigApplicationContextannotationContext=newAnnotationConfigApplicationContext(TestComponentScanConfig.class);StringDefinitions的String[]名称=注释；名称：名称）{System.out.println（名称）;具体运行效果可以查看控制台输出，是否符合预期，如有不明之处欢迎交流
