Interface LruCache<K,V>

All Known Implementing Classes:
CachingRlsLbClient.RlsAsyncLruCache, LinkedHashLruCache
interface LruCache<K,V>
An LruCache is a cache with least recently used eviction.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static interface 
    LruCache.EvictionListener<K,V>
    A Listener notifies cache eviction events.
    static enum 
    LruCache.EvictionType
    Type of cache eviction.

  • Method Summary

    Modifier and Type
    Method
    Description
    V
    cache(K key, V value)
    Populates a cache entry.
    void
    close()
    Closes underlying resources.
    int
    estimatedSize()
    Returns the estimated number of entry of the cache.
    boolean
    hasCacheEntry(K key)
    Returns true if given key is cached.
    V
    invalidate(K key)
    Invalidates an entry for given key if exists.
    void
    invalidateAll()
    Invalidates cache entries for all keys.
    V
    read(K key)
    Returns cached value for given key if exists, otherwise null.

  • Method Details

    • cache

      @Nullable V cache(K key, V value)
      Populates a cache entry. If the cache entry for given key already exists, the value will be replaced to the new value.
      Returns:
      the previous value associated with key, otherwise null

    • read

      @Nullable @CheckReturnValue V read(K key)
      Returns cached value for given key if exists, otherwise null. This operation doesn't return already expired cache entry.

    • invalidate

      @Nullable V invalidate(K key)
      Invalidates an entry for given key if exists. This operation will trigger LruCache.EvictionListener with LruCache.EvictionType.EXPLICIT.
      Returns:
      the previous value associated with key, otherwise null

    • invalidateAll

      void invalidateAll()
      Invalidates cache entries for all keys. This operation will trigger LruCache.EvictionListener with LruCache.EvictionType.EXPLICIT.

    • hasCacheEntry

      @CheckReturnValue boolean hasCacheEntry(K key)
      Returns true if given key is cached.

    • estimatedSize

      @CheckReturnValue int estimatedSize()
      Returns the estimated number of entry of the cache. Note that the size can be larger than its true size, because there might be already expired cache.

    • close

      void close()
      Closes underlying resources.