Module io.helidon.security.providers.common
Package io.helidon.security.providers.common

Interface EvictableCache<K,V>

Type Parameters:
K - type of keys in this cache
V - type of values in this cache
public interface EvictableCache<K,V>
Generic cache with eviction support. Default implementation is backed by ConcurrentHashMap and provides configuration to set this map up, as can be done through builder(), and create(io.helidon.config.Config). Cache timeouts:

  • Field Details

    • CACHE_TIMEOUT_MINUTES

      static final long CACHE_TIMEOUT_MINUTES
      Default timeout of records in minutes (inactivity timeout). Default values are valid for default implementation, custom implementations may not support such features.
      See Also:

    • CACHE_EVICT_PERIOD_MINUTES

      static final long CACHE_EVICT_PERIOD_MINUTES
      Default eviction period in minutes (how often to evict records). Default values are valid for default implementation, custom implementations may not support such features.
      See Also:

    • CACHE_EVICT_DELAY_MINUTES

      static final long CACHE_EVICT_DELAY_MINUTES
      Default eviction delay in minutes (how long to wait after the cache is started). Default values are valid for default implementation, custom implementations may not support such features.
      See Also:

    • CACHE_MAX_SIZE

      static final long CACHE_MAX_SIZE
      Maximal number of records in the cache. If the cache is full, no caching is done and the supplier of value is called for every uncached value. Default values are valid for default implementation, custom implementations may not support such features.
      See Also:

    • EVICT_PARALLELISM_THRESHOLD

      static final long EVICT_PARALLELISM_THRESHOLD
      Parameter to ConcurrentHashMap.forEachKey(long, Consumer) used for eviction. Default values are valid for default implementation, custom implementations may not support such features.
      See Also:

  • Method Details

    • builder

      static <K, V> EvictableCache.Builder<K,V> builder()
      Create a new builder for a cache that uses the default implementation.
      Type Parameters:
      K - type of keys in the cache
      V - type of values in the cache
      Returns:
      a builder to build the cache

    • create

      static <K, V> EvictableCache<K,V> create()
      Create a new cache with default values using the default implementation.
      Type Parameters:
      K - type of keys in the cache
      V - type of values in the cache
      Returns:
      new cache built with default values

    • create

      static <K, V> EvictableCache<K,V> create(Config config)
      Create a new cache and configure it from the provided configuration. See EvictableCache.Builder.config(Config) for the list of configuration keys. This will use the default implementation.
      Type Parameters:
      K - type of keys in the cache
      V - type of values in the cache
      Parameters:
      config - config to read configuration of this cache from
      Returns:
      new cache configured from config

    • noCache

      static <K, V> EvictableCache<K,V> noCache()
      Create a new cache that is not a cache (e.g. never caches, delegates all calls to the Supplier in computeValue(Object, Supplier).
      Type Parameters:
      K - Type of keys
      V - Type of values
      Returns:
      a new instance that is not caching

    • remove

      default Optional<V> remove(K key)
      Remove a key from the cache. Return the value if it was cached and valid.
      Parameters:
      key - key to remove
      Returns:
      value if it was removed and valid, empty otherwise

    • get

      default Optional<V> get(K key)
      Get current cached value if valid.
      Parameters:
      key - key to use
      Returns:
      current value in the cache or empty if not present (or invalid)

    • size

      default int size()
      Current size of the cache. This value may not represent exact current size, as the implementation is expected to be thread safe and accessed from multiple threads, that may change the size in parallel.
      Returns:
      current size of the cache (including valid and invalid - not yet evicted - values)

    • computeValue

      default Optional<V> computeValue(K key, Supplier<Optional<V>> valueSupplier)
      Either return a cached value or compute it and cache it.
      Parameters:
      key - key to check/insert value for
      valueSupplier - supplier called if the value is not yet cached, or is invalid
      Returns:
      current value from the cache, or computed value from the supplier

    • close

      default void close()
      Close this cache. Carry out shutdown tasks (e.g. shutting down eviction thread).