Package fr.gouv.vitam.common.lru

Interface InterfaceLruCache<K,​V>

  • Type Parameters:
    K - Key
    V - Value
    All Known Implementing Classes:
    SynchronizedLruCache
    public interface InterfaceLruCache<K,​V>
    LRU cache interface. author Damian Momot

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void clear()
      Removes all entries from cache
      boolean contains​(K key)
      Checks whether cache contains valid entry for key
      int forceClearOldest()
      Removes all oldest entries from cache (ttl based)
      V get​(K key)
      Returns value cached with key.
      V get​(K key, java.util.concurrent.Callable<V> callback)
      Tries to get element from cache.
      V get​(K key, java.util.concurrent.Callable<V> callback, long ttl)
      Tries to get element from cache.
      int getCapacity()
      Returns cache capacity
      long getTtl()
      Returns cache TTL
      boolean isEmpty()
      Checks whether cache is empty.
      void put​(K key, V value)
      Puts value under key into cache.
      void put​(K key, V value, long ttl)
      Puts value under key into cache with desired TTL
      V remove​(K key)
      Removes entry from cache (if exists)
      void setNewTtl​(long ttl)
      Set a new TTL (for newly set objects only, not changing old values).
      int size()
      Returns number of entries stored in cache (including invalid ones)
      void updateTtl​(K key)
      Update the TTL of the associated object if it still exists

    • Method Detail

      • clear

        void clear()
        Removes all entries from cache

      • forceClearOldest

        int forceClearOldest()
        Removes all oldest entries from cache (ttl based)
        Returns:
        the number of removed entries

      • contains

        boolean contains​(K key)
        Checks whether cache contains valid entry for key
        Parameters:
        key -
        Returns:
        true if cache contains key and entry is valid

      • get

        V get​(K key)
        Returns value cached with key.
        Parameters:
        key -
        Returns:
        value or null if key doesn't exist or entry is not valid

      • get

        V get​(K key,
      java.util.concurrent.Callable<V> callback)
throws VitamException
        Tries to get element from cache. If get fails callback is used to create element and returned value is stored in cache. Default TTL is used
        Parameters:
        key -
        callback -
        Returns:
        Value
        Throws:
        VitamException
        java.lang.Exception - if callback throws exception

      • get

        V get​(K key,
      java.util.concurrent.Callable<V> callback,
      long ttl)
throws VitamException
        Tries to get element from cache. If get fails callback is used to create element and returned value is stored in cache
        Parameters:
        key -
        callback -
        ttl - time to live in milliseconds
        Returns:
        Value
        Throws:
        VitamException
        java.lang.Exception - if callback throws exception

      • getCapacity

        int getCapacity()
        Returns cache capacity
        Returns:
        capacity of cache

      • size

        int size()
        Returns number of entries stored in cache (including invalid ones)
        Returns:
        number of entries

      • getTtl

        long getTtl()
        Returns cache TTL
        Returns:
        ttl in milliseconds

      • setNewTtl

        void setNewTtl​(long ttl)
        Set a new TTL (for newly set objects only, not changing old values).
        Parameters:
        ttl -

      • isEmpty

        boolean isEmpty()
        Checks whether cache is empty. If any entry exists (including invalid one) this method will return true
        Returns:
        true if no entries are stored in cache

      • put

        void put​(K key,
         V value)
        Puts value under key into cache. Default TTL is used
        Parameters:
        key -
        value -

      • put

        void put​(K key,
         V value,
         long ttl)
        Puts value under key into cache with desired TTL
        Parameters:
        key -
        value -
        ttl - time to live in milliseconds

      • remove

        V remove​(K key)
        Removes entry from cache (if exists)
        Parameters:
        key -
        Returns:
        the value if it still exists

      • updateTtl

        void updateTtl​(K key)
        Update the TTL of the associated object if it still exists
        Parameters:
        key -