Caffeine - how expires Cached values only after creation time

问题

Caffeine has expiresAfterWrite method which looks at last write time. I want it to look only at the creation time. So when the first entry comes then entry will be expired after a fixed amount of time without looking at the number of updates on this entry. Is this possible?

回答1:

Yes, but requires using the more advanced Expiry api. In the below example, a newly created entry has a fixed 5 minute lifetime. This is done by returning currentDuration on an update or read.

LoadingCache<Key, Graph> graphs = Caffeine.newBuilder()
    .expireAfter(new Expiry<Key, Graph>() {
      public long expireAfterCreate(Key key, Graph graph, long currentTime) {
        return TimeUnit.MINUTES.toNanos(5);
      }
      public long expireAfterUpdate(Key key, Graph graph, 
          long currentTime, long currentDuration) {
        return currentDuration;
      }
      public long expireAfterRead(Key key, Graph graph,
          long currentTime, long currentDuration) {
        return currentDuration;
      }
    })
    .build(key -> createExpensiveGraph(key));

来源：https://stackoverflow.com/questions/51779879/caffeine-how-expires-cached-values-only-after-creation-time