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Is it possible for a bolt receive multiple input tuples from different spout/bolt? For instance, Bolt C receive input tuples from Spout A and input tuples from Bolt B to be processed. How should I implement it? I mean writing the Java code for Bolt C and also its topology.

Matthias J. Sax
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Toshihiko
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  • What do you mean? I'm new here, so I don't exactly know what you mean. – Toshihiko May 23 '15 at 12:16
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2 Answers2

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Tutorial answers your question.

https://storm.apache.org/documentation/Tutorial.html

Here is the code for your goal(C/P from tutorial):

builder.setBolt("exclaim2", new ExclamationBolt(), 5)
            .shuffleGrouping("words")
            .shuffleGrouping("exclaim1");

exclaim2 will accept tuples from both words and exclaim1, both using shuffle grouping.

Seçkin Savaşçı
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  • This was helpful. It would be nice to know if chaining can be done dynamically (via a loop) also. I have a variable number of bolts that would be generated via a loop and I want all of them to send their emitted Tuples to a single bolt. `for(int i=0;i<10;++i) {builder.setBolt("a",new someBolt(),5).shuffleGrouping("Bolt"+i);}`. Each iteration of the loop should chain one more Bolt. Is it possible in any way? – Nav Apr 20 '16 at 06:46
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Yes Possible. Only thing to take care is it should follow DAG structure. In your case, below is the flow. 1. Spout reads the data and sends to bolt C 2. Same Spout reads the data and sends to bolt B 3. Bolt B filters some data and forwards to Bolt C

Hariprasad Taduru
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