Package io.github.kaststream.api.v2

Interface FlatMapper

  • All Superinterfaces:
    Serializable
    public interface FlatMapper
extends Serializable
    Implement this interface to provide your own flat map function.

    • Method Detail

      • flatMap

        void flatMap​(KastRow kRow,
             KastCollector out,
             KastRowBuilder kastRowBuilder)
      throws Exception
        Your function implementation. Do what you need on the received rows.
        Parameters:
        kRow - the received row
        out - the output row collector
        Throws:
        Exception - The function may throw exceptions which cause the streaming program to fail and go into recovery.

      • getProducedType

        org.apache.avro.Schema getProducedType​(org.apache.avro.Schema schema)
        Declare the data type information of the data produced by your function.
        Parameters:
        schema - the input row schema
        Returns:
        the produced data typeInfo

      • open

        void open​(Map<String,​String> configuration,
          org.apache.avro.Schema schema)
   throws Exception
        Initialization method for the function.
        Parameters:
        configuration - The configuration containing the parameters attached to the contract
        schema - the input row schema
        Throws:
        Exception - The function may throw exceptions which cause the streaming program to fail and go into recovery.

      • close

        void close()
    throws Exception
        Tear-down method for the user code. It is called after the last call to the main working methods. For functions that are part of an iteration, this method will be invoked after each iteration superstep.

        This method can be used for clean up work.

        Throws:
        Exception - The function may throw exceptions which cause the streaming program to fail and go into recovery.