caffeine

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Caffeine is a [high performance][benchmarks], [near optimal][efficiency] caching library. For more
details, see our [user's guide][users-guide] and browse the [API docs][javadoc] for the latest
release.

### Cache

Caffeine provides an in-memory cache using a Google Guava inspired API. The improvements draw on our
experience designing [Guava's cache][guava-cache] and [ConcurrentLinkedHashMap][clhm].

```java
LoadingCache<Key, Graph> graphs = Caffeine.newBuilder()
    .maximumSize(10_000)
    .expireAfterWrite(Duration.ofMinutes(5))
    .refreshAfterWrite(Duration.ofMinutes(1))
    .build(key -> createExpensiveGraph(key));
```

#### Features at a Glance

Caffeine provides flexible construction to create a cache with a combination of the following
optional features:

* [automatic loading of entries][population] into the cache, optionally asynchronously
* [size-based eviction][size] when a maximum is exceeded based on [frequency and recency][efficiency]
* [time-based expiration][time] of entries, measured since last access or last write
* [asynchronously refresh][refresh] when the first stale request for an entry occurs
* keys automatically wrapped in [weak references][reference]
* values automatically wrapped in [weak or soft references][reference]
* [notification][listener] of evicted (or otherwise removed) entries
* [writes propagated][compute] to an external resource
* accumulation of cache access [statistics][statistics]

In addition, Caffeine offers the following extensions:

* [JSR-107 JCache][jsr107]
* [Guava adapters][guava-adapter]
* [Simulation][simulator]

Use Caffeine in a community