SpringBoot顶层接口实现类注入项目的方法示例

public interface IBaseHandler {
    /**
     * 获取处理器类型
     * @return 处理器类型
     */
    int getType();

    /**
     * 处理业务
     * @param t 业务数据
     * @param <T> 业务数据类型
     */
    <T> void handler(T t);
}

    @Autowired
    private List<IBaseHandler> handlers;
     /**
     * 处理业务
     * @param type 业务类型
     * @param data 业务数据
     * @param <T> 业务数据类型
     */
    public <T> void handle(int type, T data) {
        handlers.stream().filter(handler -> handler.getType() == type).findAny().orElseThrow(() -> {
            // 获取不到业务类对象时打印日志并抛出异常
            log.error("Failed to get handler, type:{}", type);
            throw new NoSuchElementException("No such handler");
        }).handler(data);
    }

@Slf4j
public class HandlerManager {
    /**
     * 按照type映射的处理器map
     */
    private static Map<Integer, IBaseHandler> typeHandlerMap = new HashMap<>();
    /**
     * 按照类型映射的处理器map
     */
    private static Map<Class<IBaseHandler>, IBaseHandler> clazzHandlerMap = new HashMap<>();

    /**
     * 初始化方法，项目启动时调用该方法来初始化map
     * @param applicationContext spring 上下文对象
     */
    public static void init(ApplicationContext applicationContext) {
        List<IBaseHandler> handlers = new ArrayList<>();
        applicationContext.getBeansOfType(IBaseHandler.class).forEach((name, obj) -> handlers.add(obj));
        // 为了方便，两次循环构建map，一次循环也可以解决，不过人为定义的handler数量不多，一次循环性能提升不大
        typeHandlerMap = handlers.stream().collect(Collectors.toMap(IBaseHandler::getType, obj -> obj));
        clazzHandlerMap = handlers.stream().collect(Collectors.toMap(obj -> (Class<IBaseHandler>) obj.getClass(), obj -> obj));
    }

    public IBaseHandler getHandlerByType(int type) {
        return Optional.ofNullable(typeHandlerMap.get(type)).orElseThrow(() -> {
            // 获取不到处理器打印日志并抛出异常
            log.info("Failed to get handler, type:{}", type);
            throw new NoSuchElementException("No such  handler error");
        });
    }

    public IBaseHandler getHandlerByClass(Class<IBaseHandler> clazz) {
        return Optional.ofNullable(clazzHandlerMap.get(clazz)).orElseThrow(() -> {
            // 获取不到处理器打印日志并抛出异常
            log.info("Failed to get handler, clazz:{}", clazz);
            throw new NoSuchElementException("No such  handler error");
        });
    }


}

/**
 * 项目初始化类
 * 继承ApplicationContextAware,实现setApplicationContext，可获取ApplicationContext来获取上下文
 */
@Component
public class ApplicationInit implements ApplicationContextAware {

    @Autowired
    private List<IBaseHandler> handlers;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        // 调用处理器工具类初始化方法
        HandlerManager.init(applicationContext);
    }
}