README.md

Caffeine is a high performance, near optimal caching library based on Java 8. For more details, see our user's guide and browse the API docs 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 and ConcurrentLinkedHashMap.

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

Features at a Glance

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

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

In addition, Caffeine offers the following extensions:

• JSR-107 JCache
• Guava adapters
• Simulation

Use Caffeine in a community provided integration:

• Spring Cache (Spring 4.3 & Boot 1.4)
• ScalaCache: Simple caching in Scala
• Scaffeine: Scala wrapper for Caffeine
• Ratpack: Lean & powerful HTTP apps
• Finagle: Extensible RPC system
• Druid: Real-time Analytics

In the News

• A short look at what Caffeine brings to your applications.
  • Add a Boost of Caffeine to Your Java at VOXXED
• An in-depth description of Caffeine's architecture.
  • Design of a Modern Cache at HighScalability
• Caffeine is presented as part of a research paper evaluating its novel eviction policy.
  • TinyLFU: A Highly Efficient Cache Admission Policy by Gil Einziger, Roy Friedman, Ben Manes

On the radar,

• Early discussions with HBase, Cassandra, and Solr
• Being adopted in the Neo4j 3.1 and Infinispan 9.0 releases
• W-TinyLfu implemented by go-tinylfu, mango-cache, and ohc

Download

Download from Maven Central or depend via Gradle:

compile 'com.github.ben-manes.caffeine:caffeine:2.3.5'

// Optional extensions
compile 'com.github.ben-manes.caffeine:guava:2.3.5'
compile 'com.github.ben-manes.caffeine:jcache:2.3.5'

See the release notes for details of the changes.

Snapshots of the development version are available in Sonatype's snapshots repository.