org.apache.samza.operators.functions

Interface FoldLeftFunction<M,WV>

All Superinterfaces:

ClosableFunction, InitableFunction

public interface FoldLeftFunction<M,WV>
extends InitableFunction, ClosableFunction

Incrementally updates the window value as messages are added to the window.

Method Summary

Modifier and Type	Method and Description
WV	apply(M message, WV oldValue) Incrementally updates the window value as messages are added to the window.

Methods inherited from interface org.apache.samza.operators.functions.InitableFunction

init

Methods inherited from interface org.apache.samza.operators.functions.ClosableFunction

close

Method Detail

apply

WV apply(M message,
         WV oldValue)

Incrementally updates the window value as messages are added to the window.

Parameters:

message - the message being added to the window

oldValue - the previous value associated with the window

Returns:

the new value