Interface Processor<K,​V>

  • Type Parameters:
    K - the type of keys
    V - the type of values
    All Known Implementing Classes:
    AbstractProcessor

    @Evolving
    public interface Processor<K,​V>
    A processor of key-value pair records.
    • Method Detail

      • init

        void init​(ProcessorContext context)
        Initialize this processor with the given context. The framework ensures this is called once per processor when the topology that contains it is initialized.

        The provided context can be used to access topology and record meta data, to schedule a method to be called periodically and to access attached StateStores.

        Parameters:
        context - the context; may not be null
      • process

        void process​(K key,
                     V value)
        Process the record with the given key and value.
        Parameters:
        key - the key for the record
        value - the value for the record
      • punctuate

        @Deprecated
        void punctuate​(long timestamp)
        Deprecated.
        Please use Punctuator functional interface instead.
        Perform any periodic operations, if this processor schedule itself with the context during initialization.
        Parameters:
        timestamp - the stream time when this method is being called
      • close

        void close()
        Close this processor and clean up any resources. Be aware that close() is called after an internal cleanup. Thus, it is not possible to write anything to Kafka as underlying clients are already closed.

        Note: Do not close any streams managed resources, like StateStores here, as they are managed by the library.