Class LRUCache<K,​V>

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Cloneable, java.util.Map<K,​V>

    public class LRUCache<K,​V>
    extends java.util.LinkedHashMap<K,​V>
    An LRU implementation which limits the maximum number of entries and ejects older entries. Null values are not permitted in this implementation.
    See Also:
    Serialized Form
    • Nested Class Summary

      • Nested classes/interfaces inherited from class java.util.AbstractMap

        java.util.AbstractMap.SimpleEntry<K extends java.lang.Object,​V extends java.lang.Object>, java.util.AbstractMap.SimpleImmutableEntry<K extends java.lang.Object,​V extends java.lang.Object>
    • Constructor Summary

      Constructors 
      Constructor Description
      LRUCache​(int maxSize)
      Public constructor
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      java.util.LinkedHashMap<K,​V> newUpdateMap()
      Create a new instance of a LinkedHashMap which can be used for collecting updates to apply to the cache.
      protected boolean removeEldestEntry​(java.util.Map.Entry<K,​V> eldest)  
      void update​(java.util.LinkedHashMap<K,​V> updates)
      Update this LRU with the updates in the given LinkedHashMap, which we use because we apply the updates in a specific order (as defined by the entrySet of the updates parameter).
      void update​(java.util.List<K> updates)
      Update the LRU by processing each of the keys in the updates parameter
      • Methods inherited from class java.util.LinkedHashMap

        clear, containsValue, entrySet, forEach, get, getOrDefault, keySet, replaceAll, values
      • Methods inherited from class java.util.HashMap

        clone, compute, computeIfAbsent, computeIfPresent, containsKey, isEmpty, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, size
      • Methods inherited from class java.util.AbstractMap

        equals, hashCode, toString
      • Methods inherited from class java.lang.Object

        getClass, notify, notifyAll, wait, wait, wait
      • Methods inherited from interface java.util.Map

        compute, computeIfAbsent, computeIfPresent, containsKey, equals, hashCode, isEmpty, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, size
    • Constructor Detail

      • LRUCache

        public LRUCache​(int maxSize)
        Public constructor
        Parameters:
        maxSize -
    • Method Detail

      • removeEldestEntry

        protected boolean removeEldestEntry​(java.util.Map.Entry<K,​V> eldest)
        Overrides:
        removeEldestEntry in class java.util.LinkedHashMap<K,​V>
      • update

        public void update​(java.util.LinkedHashMap<K,​V> updates)
        Update this LRU with the updates in the given LinkedHashMap, which we use because we apply the updates in a specific order (as defined by the entrySet of the updates parameter).
        Parameters:
        updates -
      • update

        public void update​(java.util.List<K> updates)
        Update the LRU by processing each of the keys in the updates parameter
        Parameters:
        updates -
      • newUpdateMap

        public java.util.LinkedHashMap<K,​V> newUpdateMap()
        Create a new instance of a LinkedHashMap which can be used for collecting updates to apply to the cache.
        Returns:
        a new empty instance of a LinkedHashMap