Module swim.util
Package swim.util

Class HashGenMap<K,V>

java.lang.Object
swim.util.HashGenMap<K,V>
public class HashGenMap<K,V> extends Object
A hashed generational map evicts the least recently used value with the worst hit rate per hash bucket. HashGenMap is a concurrent and lock-free LRFU cache, with O(1) access time, that strongly references its values.

Maintaining four "generations" of cached values per hash bucket, the cache discards from the younger generations based on least recent usage, and promotes younger generations to older generations based on most frequent usage. Cache misses count as negative usage of the older generations, biasing the cache against least recently used values with poor hit rates.

The evict(K, V) method is guaranteed to be called when a value is displaced from the cache.

  • Constructor Details

    • HashGenMap

      public HashGenMap(int size)

  • Method Details

    • evict

      protected void evict(K key, V value)

    • get

      public V get(K key)

    • put

      public V put(K key, V value)

    • remove

      public V remove(K key)

    • clear

      public void clear()

    • hitRatio

      public double hitRatio()