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POHadoop Cascading - create flow with one source, two sinks
 

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    <p>I am using Cascading 2 to create Hadoop jobs and am trying to create a flow that starts with a single source. After a couple of functions are applied to the data I need to split the flow so that this data is used to create two separate reports (in two separate sinks).</p> <pre><code> //SOURCE Scheme sourceScheme = new TextLine( new Fields( "line" ) ); Tap source = new Hfs( sourceScheme, input ); //REPORT1 SINK Scheme report1SinkScheme = new TextDelimited( Fields.ALL, ",","\"" ); Tap report1Sink = new Hfs( report1SinkScheme, output1, SinkMode.REPLACE ); //REPORT2 SINK Scheme report2SinkScheme = new TextDelimited( Fields.ALL, ",","\"" ); Tap report2Sink = new Hfs( report2SinkScheme, output2, SinkMode.REPLACE ); //INITIAL FUNCTIONS Pipe firstPipe = new Pipe("firstPipe"); firstPipe = new Each(firstPipe, new Fields("line"), functionA); firstPipe = new Each(firstPipe, functionB, Fields.ALL); //REPORT1 FUNCTION report1Pipe = new Each(firstPipe, Fields.ALL, function1, Fields.RESULTS); //REPORT2 FUNCTION report2Pipe = new Each(firstPipe, Fields.ALL, function2, Fields.RESULTS); //CONNECT FLOW PARTS FlowDef flowDef = new FlowDef() .setName("report-flow") .addSource(firstPipe, source) .addSink(report1Pipe, report1Sink) .addSink(report2Pipe, report2Sink); new HadoopFlowConnector( properties ).connect( flowDef ).complete(); </code></pre> <p>Currently this is giving me the error "java.lang.IllegalArgumentException: cannot add duplicate sink: firstPipe" but even after messing around with it for a while I get a variety of other issues to do with the flow set up. </p> <p>Is it possible for someone to explain how to construct a flow of this form (one source, two sinks)? Do I need to create a Cascade instead? Or do I need an intermediate sink to hold the data before I split?</p> <p>Please help!</p>
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