You can do like this in your bolt for methods declareOutputFields, execute.
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declareStream("signals", new Fields("action"));
//declarer.declare(new Fields("word"));
}
public void execute(Tuple input) {
String str = input.getString(0);
if(str.equals("EOF")){
collector.emit("signals",new Values("dumpValues"));
//List a = new ArrayList();
//a.add(input);
//collector.emit(a,new Values(str));
}
// Acknowledge the tuple
collector.ack(input);
}
Then in the downstream bolt
@Override
public void execute(Tuple input) {
if (input.getSourceStreamId().equals("signals")) {
......
}
//Set the tuple as Acknowledge
collector.ack(input);
}
On 10/30/14, clay teahouse <[email protected]> wrote:
> Hello All,
>
> My data source can have multiple formats, except that all records share the
> first field. Based on the value of this field, I want to generate a
> separate stream that goes to a particular bolt for special processing. Now
> my question is how one does conditional streaming, based on a particular
> field in the stream?
>
> For example:
>
> Bolt A if field F="X" generate stream1 with certain fields that goes to
> Bolt B
> Bolt A if field F="Y" generate stream2 with certain fields that goes to
> Bolt C
>
> I am sorry if this is a trivial question, but I don't seem to be able to do
> this in a straightforward way and I can't find an example that helps.
>
> thanks,
> Clay
>
