How to use

AbstractImportSelector

in

com.nepxion.matrix.selector

@Override
public String[] selectImports(AnnotationMetadata metadata) {
  if (!isEnabled()) {
    return new String[0];
  }
  AnnotationAttributes attributes = AnnotationAttributes.fromMap(metadata.getAnnotationAttributes(this.annotationClass.getName(), true));
  Assert.notNull(attributes, "No " + getSimpleName() + " attributes found. Is " + metadata.getClassName() + " annotated with @" + getSimpleName() + "?");
  // Find all possible auto configuration classes, filtering duplicates
  List<String> factories = new ArrayList<>(new LinkedHashSet<>(SpringFactoriesLoader.loadFactoryNames(this.annotationClass, this.beanClassLoader)));
  if (factories.isEmpty() && !hasDefaultFactory()) {
    throw new IllegalStateException("Annotation @" + getSimpleName() + " found, but there are no implementations. Did you forget to include a starter?");
  }
  if (factories.size() > 1) {
    // there should only ever be one DiscoveryClient, but there might be more than one factory
    LOG.warn("More than one implementation " + "of @" + getSimpleName() + " (now relying on @Conditionals to pick one): " + factories);
  }
  return factories.toArray(new String[factories.size()]);
}

@Override
public String[] selectImports(AnnotationMetadata metadata) {
  // 获取父类的Configuration列表
  String[] imports = super.selectImports(metadata);
  // 从注解上获取参数
  AnnotationAttributes attributes = AnnotationAttributes.fromMap(metadata.getAnnotationAttributes(getAnnotationClass().getName(), true));
  boolean extension = attributes.getBoolean("extension");
  if (extension) {
    // 如果EnableMyAnnotation注解上的extension为true，那么去装载MyConfigurationExtension，即初始化里面的MyBeanExtension
    List<String> importsList = new ArrayList<>(Arrays.asList(imports));
    importsList.add(MyConfigurationExtension.class.getCanonicalName());
    imports = importsList.toArray(new String[0]);
  } else {
    // 如果EnableMyAnnotation注解上的extension为false，那么你可以把该参数动态放到属性列表里
    Environment environment = getEnvironment();
    if (ConfigurableEnvironment.class.isInstance(environment)) {
      ConfigurableEnvironment configurableEnvironment = (ConfigurableEnvironment) environment;
      LinkedHashMap<String, Object> map = new LinkedHashMap<>();
      map.put("extension.enabled", false);
      MapPropertySource propertySource = new MapPropertySource("nepxion", map);
      configurableEnvironment.getPropertySources().addLast(propertySource);
    }
  }
  return imports;
}