Interface Cache<K,​V>

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      java.util.concurrent.ConcurrentMap<K,​V> asMap()
      Returns a view of the entries stored in this cache as a thread-safe map.
      void cleanUp()
      Performs any pending maintenance operations needed by the cache.
      V get​(K key, java.util.concurrent.Callable<? extends V> valueLoader)
      Returns the value associated with key in this cache, obtaining that value from valueLoader if necessary.
      ImmutableMap<K,​V> getAllPresent​(java.lang.Iterable<?> keys)
      Returns a map of the values associated with keys in this cache.
      V getIfPresent​(java.lang.Object key)
      Returns the value associated with key in this cache, or null if there is no cached value for key.
      void invalidate​(java.lang.Object key)
      Discards any cached value for key key.
      void invalidateAll()
      Discards all entries in the cache.
      void invalidateAll​(java.lang.Iterable<?> keys)
      Discards any cached values for keys keys.
      void put​(K key, V value)
      Associates value with key in this cache.
      void putAll​(java.util.Map<? extends K,​? extends V> m)
      Copies all of the mappings from the specified map to the cache.
      long size()
      Returns the approximate number of entries in this cache.
      CacheStats stats()
      Returns a current snapshot of this cache's cumulative statistics.
    • Method Detail

      • getIfPresent

        @Nullable
        V getIfPresent​(java.lang.Object key)
        Returns the value associated with key in this cache, or null if there is no cached value for key.
        Since:
        11.0
      • get

        V get​(K key,
              java.util.concurrent.Callable<? extends V> valueLoader)
        throws java.util.concurrent.ExecutionException
        Returns the value associated with key in this cache, obtaining that value from valueLoader if necessary. No observable state associated with this cache is modified until loading completes. This method provides a simple substitute for the conventional "if cached, return; otherwise create, cache and return" pattern.

        Warning: as with CacheLoader.load(K), valueLoader must not return null; it may either return a non-null value or throw an exception.

        Throws:
        java.util.concurrent.ExecutionException - if a checked exception was thrown while loading the value
        UncheckedExecutionException - if an unchecked exception was thrown while loading the value
        ExecutionError - if an error was thrown while loading the value
        Since:
        11.0
      • getAllPresent

        ImmutableMap<K,​V> getAllPresent​(java.lang.Iterable<?> keys)
        Returns a map of the values associated with keys in this cache. The returned map will only contain entries which are already present in the cache.
        Since:
        11.0
      • put

        void put​(K key,
                 V value)
        Associates value with key in this cache. If the cache previously contained a value associated with key, the old value is replaced by value.

        Prefer get(Object, Callable) when using the conventional "if cached, return; otherwise create, cache and return" pattern.

        Since:
        11.0
      • putAll

        void putAll​(java.util.Map<? extends K,​? extends V> m)
        Copies all of the mappings from the specified map to the cache. The effect of this call is equivalent to that of calling put(k, v) on this map once for each mapping from key k to value v in the specified map. The behavior of this operation is undefined if the specified map is modified while the operation is in progress.
        Since:
        12.0
      • invalidate

        void invalidate​(java.lang.Object key)
        Discards any cached value for key key.
      • invalidateAll

        void invalidateAll​(java.lang.Iterable<?> keys)
        Discards any cached values for keys keys.
        Since:
        11.0
      • invalidateAll

        void invalidateAll()
        Discards all entries in the cache.
      • size

        long size()
        Returns the approximate number of entries in this cache.
      • stats

        CacheStats stats()
        Returns a current snapshot of this cache's cumulative statistics. All stats are initialized to zero, and are monotonically increasing over the lifetime of the cache.
      • asMap

        java.util.concurrent.ConcurrentMap<K,​V> asMap()
        Returns a view of the entries stored in this cache as a thread-safe map. Modifications made to the map directly affect the cache.
      • cleanUp

        void cleanUp()
        Performs any pending maintenance operations needed by the cache. Exactly which activities are performed -- if any -- is implementation-dependent.