Hazelcast Jet StreamStageWithKey İşlemleri

Giriş

Şu satırı dahil ederiz

import com.hazelcast.jet.pipeline.StreamStageWithKey;

filterStateful metodu

3 parametre alır

- ttl

- create function

- filter function

Örnek - deduplication

Şöyle yaparız

stage.groupingKey(AddNewComment::getUuid)
  .filterStateful(
    10_000, 
    () -> new boolean[1],
    (s, i) -> {
      boolean res = s[0];
      s[0] = true;
      return !res;
    }
);

Açıklaması şöyle

The first parameter in the filterStateful() method is time-to-live. Event time is typically in milliseconds. This means each state object will be retained for at least 10 seconds. We have to choose this parameter to match the longest possible time window between two duplicated elements.