Class LocalAsyncCache.AbstractCacheView<K,V>

java.lang.Object
com.github.benmanes.caffeine.cache.LocalAsyncCache.AbstractCacheView<K,V>
All Implemented Interfaces:
Cache<K,V>, Serializable
Direct Known Subclasses:
LocalAsyncCache.CacheView, LocalAsyncLoadingCache.LoadingCacheView
Enclosing interface:
LocalAsyncCache<K,V>
public abstract static class LocalAsyncCache.AbstractCacheView<K,V> extends Object implements Cache<K,V>, Serializable
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    (package private) @Nullable LocalAsyncCache.AsMapView<K,V>
    asMapView
     

  • Constructor Summary

    Constructors
    Constructor
    Description
    AbstractCacheView()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    ConcurrentMap<K,V>
    asMap()
    Returns a view of the entries stored in this cache as a thread-safe map.
    (package private) abstract LocalAsyncCache<K,V>
    asyncCache()
     
    void
    cleanUp()
    Performs any pending maintenance operations needed by the cache.
    long
    estimatedSize()
    Returns the approximate number of entries in this cache.
    V
    get(K key, Function<? super K, ? extends V> mappingFunction)
    Returns the value associated with the key in this cache, obtaining that value from the mappingFunction if necessary.
    Map<K,V>
    getAll(Iterable<? extends K> keys, Function<Iterable<? extends K>, Map<K,V>> mappingFunction)
    Returns a map of the values associated with the keys, creating or retrieving those values if necessary.
    Map<K,V>
    getAllPresent(Iterable<?> keys)
    Returns a map of the values associated with the keys in this cache.
    @Nullable V
    getIfPresent(Object key)
    Returns the value associated with the key in this cache, or null if there is no cached value for the key.
    void
    invalidate(Object key)
    Discards any cached value for the key.
    void
    invalidateAll()
    Discards all entries in the cache.
    void
    invalidateAll(Iterable<?> keys)
    Discards any cached values for the keys.
    Policy<K,V>
    policy()
    Returns access to inspect and perform low-level operations on this cache based on its runtime characteristics.
    void
    put(K key, V value)
    Associates the value with the key in this cache.
    void
    putAll(Map<? extends K, ? extends V> map)
    Copies all of the mappings from the specified map to the cache.
    protected static <T> T
    resolve(CompletableFuture<T> future)
     
    CacheStats
    stats()
    Returns a current snapshot of this cache's cumulative statistics.

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

  • Constructor Details

    • AbstractCacheView

      public AbstractCacheView()

  • Method Details

    • asyncCache

      abstract LocalAsyncCache<K,V> asyncCache()

    • getIfPresent

      public @Nullable V getIfPresent(Object key)
      Description copied from interface: Cache
      Returns the value associated with the key in this cache, or null if there is no cached value for the key.
      Specified by:
      getIfPresent in interface Cache<K,V>
      Parameters:
      key - the key whose associated value is to be returned
      Returns:
      the value to which the specified key is mapped, or null if this cache contains no mapping for the key

    • getAllPresent

      public Map<K,V> getAllPresent(Iterable<?> keys)
      Description copied from interface: Cache
      Returns a map of the values associated with the keys in this cache. The returned map will only contain entries which are already present in the cache.

      Note that duplicate elements in keys, as determined by Object.equals(Object), will be ignored.

      Specified by:
      getAllPresent in interface Cache<K,V>
      Parameters:
      keys - the keys whose associated values are to be returned
      Returns:
      the unmodifiable mapping of keys to values for the specified keys found in this cache

    • get

      public V get(K key, Function<? super K, ? extends V> mappingFunction)
      Description copied from interface: Cache
      Returns the value associated with the key in this cache, obtaining that value from the mappingFunction if necessary. This method provides a simple substitute for the conventional "if cached, return; otherwise create, cache and return" pattern.

      If the specified key is not already associated with a value, attempts to compute its value using the given mapping function and enters it into this cache unless null. The entire method invocation is performed atomically, so the function is applied at most once per key. Some attempted update operations on this cache by other threads may be blocked while the computation is in progress, so the computation should be short and simple, and must not attempt to update any other mappings of this cache.

      Warning: as with CacheLoader.load(K), mappingFunction must not attempt to update any other mappings of this cache.

      Specified by:
      get in interface Cache<K,V>
      Parameters:
      key - the key with which the specified value is to be associated
      mappingFunction - the function to compute a value
      Returns:
      the current (existing or computed) value associated with the specified key, or null if the computed value is null

    • getAll

      public Map<K,V> getAll(Iterable<? extends K> keys, Function<Iterable<? extends K>, Map<K,V>> mappingFunction)
      Description copied from interface: Cache
      Returns a map of the values associated with the keys, creating or retrieving those values if necessary. The returned map contains entries that were already cached, combined with the newly loaded entries; it will never contain null keys or values.

      A single request to the mappingFunction is performed for all keys which are not already present in the cache. All entries returned by mappingFunction will be stored in the cache, over-writing any previously cached values. If another call to Cache.get(K, Function) tries to load the value for a key in keys, implementations may either have that thread load the entry or simply wait for this thread to finish and return the loaded value. In the case of overlapping non-blocking loads, the last load to complete will replace the existing entry. Note that multiple threads can concurrently load values for distinct keys. Any loaded values for keys that were not specifically requested will not be returned, but will be stored in the cache.

      Note that duplicate elements in keys, as determined by Object.equals(Object), will be ignored.

      Specified by:
      getAll in interface Cache<K,V>
      Parameters:
      keys - the keys whose associated values are to be returned
      mappingFunction - the function to compute the values
      Returns:
      an unmodifiable mapping of keys to values for the specified keys in this cache

    • resolve

      protected static <T> T resolve(CompletableFuture<T> future) throws Error
      Throws:
      Error

    • put

      public void put(K key, V value)
      Description copied from interface: Cache
      Associates the value with the key in this cache. If the cache previously contained a value associated with the key, the old value is replaced by the new value.

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

      Specified by:
      put in interface Cache<K,V>
      Parameters:
      key - the key with which the specified value is to be associated
      value - value to be associated with the specified key

    • putAll

      public void putAll(Map<? extends K, ? extends V> map)
      Description copied from interface: Cache
      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.
      Specified by:
      putAll in interface Cache<K,V>
      Parameters:
      map - the mappings to be stored in this cache

    • invalidate

      public void invalidate(Object key)
      Description copied from interface: Cache
      Discards any cached value for the key. The behavior of this operation is undefined for an entry that is being loaded (or reloaded) and is otherwise not present.
      Specified by:
      invalidate in interface Cache<K,V>
      Parameters:
      key - the key whose mapping is to be removed from the cache

    • invalidateAll

      public void invalidateAll(Iterable<?> keys)
      Description copied from interface: Cache
      Discards any cached values for the keys. The behavior of this operation is undefined for an entry that is being loaded (or reloaded) and is otherwise not present.
      Specified by:
      invalidateAll in interface Cache<K,V>
      Parameters:
      keys - the keys whose associated values are to be removed

    • invalidateAll

      public void invalidateAll()
      Description copied from interface: Cache
      Discards all entries in the cache. The behavior of this operation is undefined for an entry that is being loaded (or reloaded) and is otherwise not present.
      Specified by:
      invalidateAll in interface Cache<K,V>

    • estimatedSize

      public long estimatedSize()
      Description copied from interface: Cache
      Returns the approximate number of entries in this cache. The value returned is an estimate; the actual count may differ if there are concurrent insertions or removals, or if some entries are pending removal due to expiration or weak/soft reference collection. In the case of stale entries this inaccuracy can be mitigated by performing a Cache.cleanUp() first.
      Specified by:
      estimatedSize in interface Cache<K,V>
      Returns:
      the estimated number of mappings

    • stats

      public CacheStats stats()
      Description copied from interface: Cache
      Returns a current snapshot of this cache's cumulative statistics. All statistics are initialized to zero, and are monotonically increasing over the lifetime of the cache.

      Due to the performance penalty of maintaining statistics, some implementations may not record the usage history immediately or at all.

      Specified by:
      stats in interface Cache<K,V>
      Returns:
      the current snapshot of the statistics of this cache

    • cleanUp

      public void cleanUp()
      Description copied from interface: Cache
      Performs any pending maintenance operations needed by the cache. Exactly which activities are performed -- if any -- is implementation-dependent.
      Specified by:
      cleanUp in interface Cache<K,V>

    • policy

      public Policy<K,V> policy()
      Description copied from interface: Cache
      Returns access to inspect and perform low-level operations on this cache based on its runtime characteristics. These operations are optional and dependent on how the cache was constructed and what abilities the implementation exposes.
      Specified by:
      policy in interface Cache<K,V>
      Returns:
      access to inspect and perform advanced operations based on the cache's characteristics

    • asMap

      public ConcurrentMap<K,V> asMap()
      Description copied from interface: Cache
      Returns a view of the entries stored in this cache as a thread-safe map. Modifications made to the map directly affect the cache.

      A computation operation, such as ConcurrentMap.compute(K, BiFunction), performs the entire method invocation atomically, so the function is applied at most once per key. Some attempted update operations by other threads may be blocked while computation is in progress. The computation must not attempt to update any other mappings of this cache.

      Iterators from the returned map are at least weakly consistent: they are safe for concurrent use, but if the cache is modified (including by eviction) after the iterator is created, it is undefined which of the changes (if any) will be reflected in that iterator.

      Specified by:
      asMap in interface Cache<K,V>
      Returns:
      a thread-safe view of this cache supporting all of the optional Map operations