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javaapache-flinkdeprecated

Flink KeyBy fields

I am trying to use the keyby function with a given field, however, IntelliJ is telling me that this option is deprecated.

// map each job event to a 2-tuple
DataStream<Tuple2<Long, Long>> mappedEvents =  events.map(new AppendOneMapper()).slotSharingGroup("2");

// group the stream of tuples by jobId
KeyedStream<Tuple2<Long, Long>, Tuple> keyedEvents = mappedEvents.keyBy(0);

How would I use new methods to correctly do this?

Solution

  • KeyBy with integers or strings is deprecated. From documentation: "Deprecated. Use keyBy(KeySelector)."

    org.apache.flink.api.java.functions
Interface KeySelector<IN,KEY>
Type Parameters:
IN - Type of objects to extract the key from.
KEY - Type of key.

    KeySelector is a functional interface, so you can just plug in lambda expression.

    Replace

    .keyBy(key)

    With

    .keyBy(event -> event.getKey())