org.apache.pulsar.functions.api.examples.WordCountFunction Maven / Gradle / Ivy
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package org.apache.pulsar.functions.api.examples;
import java.util.Arrays;
import org.apache.pulsar.functions.api.Context;
import org.apache.pulsar.functions.api.Function;
/**
* The classic word count example done using pulsar functions
* Each input message is a sentence that split into words and each word counted.
* The built in counter state is used to keep track of the word count in a
* persistent and consistent manner.
*/
public class WordCountFunction implements Function {
@Override
public Void process(String input, Context context) {
Arrays.asList(input.split("\\s+")).forEach(word -> context.incrCounter(word, 1));
return null;
}
}