Question

运行拓扑时，我在NullPointerException方法中获取backtype.storm.utils.DisruptorQueue.consumeBatchToCursor，特别是在螺栓中。 Spouts正式执行。

Storm的故障排除page表示可能是由于多个线程在OutputCollector上发布方法。但是，我看不出它与我的情况有什么关系。

这是鲸鱼喷水的代码：

(defspout stub-spout ["stub-spout"]
  [conf context collector]
  (spout
    (nextTuple []
      (let [channel-value (<!! storm-async-channel)]
        (emit-spout! collector [channel-value])))
    (ack [id]
      ))))

和螺栓：

(defbolt stub-bolt ["stub-bolt"] [tuple collector]
  (println "Invocation!")
  (let [obj (get tuple "object")
        do-some-calculations (resolve 'calclib/do-some-calculations)
        new-obj (do-some-calculations obj)]
    (emit-bolt! collector new-obj)))

经过一番调查后发现，对resolve的调用返回null（我需要resolve在运行时，因为某些计算发生在位于calclib的宏中。

但代码在本地群集中正常运行。为什么会这样？

对任何建议都会感激不尽。谢谢！

Answer 1

我想我已经找到了解决方案。螺栓定义更改为准备好的螺栓：

(defbolt stub-bolt ["stub-bolt"] 
  {:prepare true}
  [conf context collector]
  (let [f (load "/calclib/core")
        do-some-calculations (resolve 'calclib/do-some-calculations)]
    (bolt
      (execute [tuple]  
        (let [obj (get tuple "object")
              new-obj (do-some-calculations obj)]
          (emit-bolt! collector new-obj))))))

键是对load的调用。我不知道是否有更优雅的方法。

运行拓扑时，Storm中的NullPointerException

1 个答案: