Class CommonCache<K,​V>

    • Field Detail

      • DEFAULT_LOAD_FACTOR

        public static final float DEFAULT_LOAD_FACTOR
        The default load factor
        See Also:
        Constant Field Values
      • DEFAULT_INITIAL_CAPACITY

        public static final int DEFAULT_INITIAL_CAPACITY
        The default initial capacity
        See Also:
        Constant Field Values
    • Constructor Detail

      • CommonCache

        public CommonCache()
        Constructs a cache with unlimited size
      • CommonCache

        public CommonCache​(int initialCapacity,
                           int maxSize,
                           EvictableCache.EvictionStrategy evictionStrategy)
        Constructs a cache with limited size
        Parameters:
        initialCapacity - initial capacity of the cache
        maxSize - max size of the cache
        evictionStrategy - LRU or FIFO, see EvictableCache.EvictionStrategy
      • CommonCache

        public CommonCache​(int initialCapacity,
                           int maxSize)
        Constructs a LRU cache with the specified initial capacity and max size. The LRU cache is slower than LRUCache
        Parameters:
        initialCapacity - initial capacity of the LRU cache
        maxSize - max size of the LRU cache
      • CommonCache

        public CommonCache​(int maxSize)
        Constructs a LRU cache with the default initial capacity
        Parameters:
        maxSize - max size of the LRU cache
        See Also:
        CommonCache(int, int)
      • CommonCache

        public CommonCache​(Map<K,​V> map)
        Constructs a cache backed by the specified Map instance
        Parameters:
        map - the Map instance
    • Method Detail

      • get

        public V get​(Object key)
        Gets a value from the cache
        Specified by:
        get in interface Map<K,​V>
        Specified by:
        get in interface MemoizeCache<K,​V>
        Parameters:
        key - the key whose associated value is to be returned
        Returns:
        the value, or null, if it does not exist.
      • put

        public V put​(K key,
                     V value)
        Associates the specified value with the specified key in the cache.
        Specified by:
        put in interface Map<K,​V>
        Specified by:
        put in interface MemoizeCache<K,​V>
        Parameters:
        key - key with which the specified value is to be associated
        value - value to be associated with the specified key
        Returns:
        null, or the old value if the key associated with the specified key.
      • getAndPut

        public V getAndPut​(K key,
                           MemoizeCache.ValueProvider<? super K,​? extends V> valueProvider)
        Try to get the value from cache. If not found, create the value by MemoizeCache.ValueProvider and put it into the cache, at last return the value.
        Specified by:
        getAndPut in interface MemoizeCache<K,​V>
        Parameters:
        key - the key to look up
        valueProvider - provide the value if the associated value not found
        Returns:
        the cached value
      • keys

        public Set<K> keys()
        Get all keys associated to cached values
        Specified by:
        keys in interface EvictableCache<K,​V>
        Returns:
        all keys
      • containsKey

        public boolean containsKey​(Object key)
        Determines if the cache contains an entry for the specified key.
        Specified by:
        containsKey in interface EvictableCache<K,​V>
        Specified by:
        containsKey in interface Map<K,​V>
        Parameters:
        key - key whose presence in this cache is to be tested.
        Returns:
        true if the cache contains a mapping for the specified key
      • size

        public int size()
        Get the size of the cache
        Specified by:
        size in interface EvictableCache<K,​V>
        Specified by:
        size in interface Map<K,​V>
        Returns:
        the size of the cache
      • isEmpty

        public boolean isEmpty()
        Specified by:
        isEmpty in interface Map<K,​V>
      • remove

        public V remove​(Object key)
        Remove the cached value by the key
        Specified by:
        remove in interface EvictableCache<K,​V>
        Specified by:
        remove in interface Map<K,​V>
        Parameters:
        key - of the cached value
        Returns:
        returns the removed value
      • putAll

        public void putAll​(Map<? extends K,​? extends V> m)
        Specified by:
        putAll in interface Map<K,​V>
      • keySet

        public Set<K> keySet()
        Specified by:
        keySet in interface Map<K,​V>
      • clearAll

        public Map<K,​V> clearAll()
        Clear the cache
        Specified by:
        clearAll in interface EvictableCache<K,​V>
        Returns:
        returns the content of the cleared map
      • cleanUpNullReferences

        public void cleanUpNullReferences()
        Invoked when some of the held SoftReferences have been evicted by the garbage collector and so should be removed from the cache. The implementation must ensure that concurrent invocations of all methods on the cache may occur from other threads and thus should protect any shared resources.
        Specified by:
        cleanUpNullReferences in interface MemoizeCache<K,​V>
      • convertValue

        public Object convertValue​(V value)
        convert the original value to the target value
        Specified by:
        convertValue in interface ValueConvertable<K,​V>
        Parameters:
        value - the original value
        Returns:
        the converted value