Class Reference2ReferenceOpenHashMap<K,​V>

  • All Implemented Interfaces:
    Function<K,​V>, Hash, Reference2ReferenceFunction<K,​V>, Reference2ReferenceMap<K,​V>, Serializable, Cloneable, Function<K,​V>, Map<K,​V>

    public class Reference2ReferenceOpenHashMap<K,​V>
    extends AbstractReference2ReferenceMap<K,​V>
    implements Serializable, Cloneable, Hash
    A type-specific hash map with a fast, small-footprint implementation.

    Instances of this class use a hash table to represent a map. The table is filled up to a specified load factor, and then doubled in size to accommodate new entries. If the table is emptied below one fourth of the load factor, it is halved in size; however, the table is never reduced to a size smaller than that at creation time: this approach makes it possible to create maps with a large capacity in which insertions and deletions do not cause immediately rehashing. Moreover, halving is not performed when deleting entries from an iterator, as it would interfere with the iteration process.

    Note that clear() does not modify the hash table size. Rather, a family of trimming methods lets you control the size of the table; this is particularly useful if you reuse instances of this class.

    Entries returned by the type-specific Reference2ReferenceMap.entrySet() method implement the suitable type-specific Pair interface; only values are mutable.

    See Also:
    Hash, HashCommon, Serialized Form
    • Constructor Detail

      • Reference2ReferenceOpenHashMap

        public Reference2ReferenceOpenHashMap​(int expected,
                                              float f)
        Creates a new hash map.

        The actual table size will be the least power of two greater than expected/f.

        Parameters:
        expected - the expected number of elements in the hash map.
        f - the load factor.
      • Reference2ReferenceOpenHashMap

        public Reference2ReferenceOpenHashMap​(int expected)
        Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor.
        Parameters:
        expected - the expected number of elements in the hash map.
      • Reference2ReferenceOpenHashMap

        public Reference2ReferenceOpenHashMap​(Map<? extends K,​? extends V> m,
                                              float f)
        Creates a new hash map copying a given one.
        Parameters:
        m - a Map to be copied into the new hash map.
        f - the load factor.
      • Reference2ReferenceOpenHashMap

        public Reference2ReferenceOpenHashMap​(Map<? extends K,​? extends V> m)
        Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given one.
        Parameters:
        m - a Map to be copied into the new hash map.
      • Reference2ReferenceOpenHashMap

        public Reference2ReferenceOpenHashMap​(Reference2ReferenceMap<K,​V> m,
                                              float f)
        Creates a new hash map copying a given type-specific one.
        Parameters:
        m - a type-specific map to be copied into the new hash map.
        f - the load factor.
      • Reference2ReferenceOpenHashMap

        public Reference2ReferenceOpenHashMap​(Reference2ReferenceMap<K,​V> m)
        Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given type-specific one.
        Parameters:
        m - a type-specific map to be copied into the new hash map.
      • Reference2ReferenceOpenHashMap

        public Reference2ReferenceOpenHashMap​(K[] k,
                                              V[] v,
                                              float f)
        Creates a new hash map using the elements of two parallel arrays.
        Parameters:
        k - the array of keys of the new hash map.
        v - the array of corresponding values in the new hash map.
        f - the load factor.
        Throws:
        IllegalArgumentException - if k and v have different lengths.
      • Reference2ReferenceOpenHashMap

        public Reference2ReferenceOpenHashMap​(K[] k,
                                              V[] v)
        Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor using the elements of two parallel arrays.
        Parameters:
        k - the array of keys of the new hash map.
        v - the array of corresponding values in the new hash map.
        Throws:
        IllegalArgumentException - if k and v have different lengths.