Spring ClassPathBeanDefinitionScanner

public class ClassPathBeanDefinitionScanner extends ClassPathScanningCandidateComponentProvider {

    /**
     * bean定义注册器
     */
    private final BeanDefinitionRegistry registry;

    /**
     * bean 定义的默认值
     */
    private BeanDefinitionDefaults beanDefinitionDefaults = new BeanDefinitionDefaults();

    /**
     * 候选对象名称列表(名称匹配模式)
     */
    @Nullable
    private String[] autowireCandidatePatterns;

    /**
     * BeanName 生成器
     */
    private BeanNameGenerator beanNameGenerator = AnnotationBeanNameGenerator.INSTANCE;

    /**
     * 作用域解析器(解析作用域元数据)
     */
    private ScopeMetadataResolver scopeMetadataResolver = new AnnotationScopeMetadataResolver();

    /**
     * 是否包含注解的配置信息
     */
    private boolean includeAnnotationConfig = true;
}

protected Set<BeanDefinitionHolder> doScan(String... basePackages) {
   Assert.notEmpty(basePackages, "At least one base package must be specified");
   // bean 定义持有器列表
   Set<BeanDefinitionHolder> beanDefinitions = new LinkedHashSet<>();
   // 循环包路径进行扫描
   for (String basePackage : basePackages) {
      // 搜索可能的组件. 得到 组件的BeanDefinition
      Set<BeanDefinition> candidates = findCandidateComponents(basePackage);
      // 循环候选bean定义
      for (BeanDefinition candidate : candidates) {
         // 获取 作用域元数据
         ScopeMetadata scopeMetadata = this.scopeMetadataResolver.resolveScopeMetadata(candidate);
         // 设置作用域
         candidate.setScope(scopeMetadata.getScopeName());
         // beanName 生成
         String beanName = this.beanNameGenerator.generateBeanName(candidate, this.registry);
         // 类型判断 AbstractBeanDefinition
         if (candidate instanceof AbstractBeanDefinition) {
            // bean 定义的后置处理
            postProcessBeanDefinition((AbstractBeanDefinition) candidate, beanName);
         }
         // 类型判断 AnnotatedBeanDefinition
         if (candidate instanceof AnnotatedBeanDefinition) {
            // 通用注解的处理
            AnnotationConfigUtils.processCommonDefinitionAnnotations((AnnotatedBeanDefinition) candidate);
         }
         // 候选检测
         if (checkCandidate(beanName, candidate)) {
            BeanDefinitionHolder definitionHolder = new BeanDefinitionHolder(candidate, beanName);
            // 作用于属性应用
            definitionHolder =
                  AnnotationConfigUtils.applyScopedProxyMode(scopeMetadata, definitionHolder, this.registry);
            beanDefinitions.add(definitionHolder);
            // 注册 bean定义
            registerBeanDefinition(definitionHolder, this.registry);
         }
      }
   }
   return beanDefinitions;
}