Use the No Operation forwarder-type Function to filter out records from your the stream. This is a forwarder.
Any record sent to this function Function is discarded from the stream and is not processed further.
Every stream must end with a forwarder, but it may be the case that your stream processes your data within a combination of collectors and processors. You can then add this function Function to your stream to complete it without the function it taking any action on the output data.
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