如何在风暴中向元组发送不同的污点

everyone.I want to do the job—— one spout emit numbers to blotA,and BlotA emit odd number to Blot_odd , BlotA emit even number to Blot_even. I choose one way to use emit(streamId,tuple),but I don't know where to define my streamId?

每个人。我想做这个工作 - 一个喷口发出数字到blotA,BlotA向Blot_odd发出奇数,BlotA向Blot_even发出偶数。我选择一种方法来使用emit(streamId,tuple),但我不知道在哪里定义我的streamId?

In the Blot_odd / Blot_even ,

在Blot_odd / Blot_even中,

declareOutputFields(){declarer.declareStream("streamId", new Fields("fieldName"));}

and in main of MyTopology.java

以及MyTopology.java的主要内容

main() {
    TopologyBuilder builder = new TopologyBuilder();
    builder.setSpout("num", new NumSpout(), 10);
    builder.setBolt("judge", new Bolt(), 3).shuffleGrouping("num");
    builder.setBolt("odd", new Bolt_odd(), 2).shuffleGrouping("judge");
    builder.setBolt("even", new Bolt_even(), 2).shuffleGrouping("judge");
}

but I failed.

但我失败了。

1 个解决方案

#1

You can do like below.

你可以在下面这样做。

in declareOutputFields method of Bolt, fill in the details like this.

在Bolt的declareOutputFields方法中,填写这样的细节。

declarer.declareStream("oddstream", new Fields("fieldName"));
declarer.declareStream("evenstream", new Fields("fieldName"));

And you can declare topology like below.

您可以声明如下的拓扑。

builder.setSpout("num", new NumSpout(), 10);
builder.setBolt("judge", new Bolt(), 3).shuffleGrouping("num");
builder.setBolt("odd", new Bolt_odd(), 2).shuffleGrouping("judge", "oddstream");
builder.setBolt("even", new Bolt_even(), 2).shuffleGrouping("judge", "evenstream");

#1