@SentinelResource 注解 fallback 的含义

使用Sentinel注解，配置了fallback，发现throw exception不起作用，通过阅读源码

@Aspect public class SentinelResourceAspect { ....

    try {
        ContextUtil.enter(resourceName);
        entry = SphU.entry(resourceName, entryType);
        Object result = pjp.proceed();
        return result;
    } catch (BlockException ex) {
        return handleBlockException(pjp, annotation, ex);
    } finally {
        if (entry != null) {
            entry.exit();
        }
        ContextUtil.exit();
    }

只有在捕获 BlockException 时才进入handleBlockException

private Object handleBlockException(ProceedingJoinPoint pjp, SentinelResource annotation, BlockException ex) throws Exception { // Execute fallback for degrading if configured. Object[] originArgs = pjp.getArgs(); if (isDegradeFailure(ex)) { Method method = extractFallbackMethod(pjp, annotation.fallback()); if (method != null) { return method.invoke(pjp.getTarget(), originArgs); } } // Execute block handler if configured. Method blockHandler = extractBlockHandlerMethod(pjp, annotation.blockHandler(), annotation.blockHandlerClass()); if (blockHandler != null) { // Construct args. Object[] args = Arrays.copyOf(originArgs, originArgs.length + 1); args[args.length - 1] = ex; if (isStatic(blockHandler)) { return blockHandler.invoke(null, args); } return blockHandler.invoke(pjp.getTarget(), args); } // If no block handler is present, then directly throw the exception. throw ex; }

换句话说，@SentinelResource的fallback只在抛出BlockException时才会触发fallback等相关策略？

原提问者GitHub用户anjia0532