Class RegularImmutableMultiset<E>

All Implemented Interfaces:
Multiset<E>, Serializable, Iterable<E>, Collection<E>

class RegularImmutableMultiset<E> extends ImmutableMultiset<E>
Implementation of ImmutableMultiset with zero or more elements.
  • Field Details

    • EMPTY_ARRAY

      private static final Multisets.ImmutableEntry<?>[] EMPTY_ARRAY
    • EMPTY

      static final ImmutableMultiset<Object> EMPTY
    • MAX_LOAD_FACTOR

      static final double MAX_LOAD_FACTOR
      Closed addressing tends to perform well even with high load factors. Being conservative here ensures that the table is still likely to be relatively sparse (hence it misses fast) while saving space.
      See Also:
    • HASH_FLOODING_FPP

      static final double HASH_FLOODING_FPP
      Maximum allowed false positive probability of detecting a hash flooding attack given random input.
      See Also:
    • MAX_HASH_BUCKET_LENGTH

      static final int MAX_HASH_BUCKET_LENGTH
      Maximum allowed length of a hash table bucket before falling back to a j.u.HashMap based implementation. Experimentally determined.
      See Also:
    • entries

      private final transient Multisets.ImmutableEntry<E>[] entries
    • hashTable

      private final transient Multisets.ImmutableEntry<?>[] hashTable
    • size

      private final transient int size
    • hashCode

      private final transient int hashCode
    • elementSet

      @CheckForNull private transient ImmutableSet<E> elementSet
  • Constructor Details

  • Method Details

    • create

      static <E> ImmutableMultiset<E> create(Collection<? extends Multiset.Entry<? extends E>> entries)
    • hashFloodingDetected

      private static boolean hashFloodingDetected(Multisets.ImmutableEntry<?>[] hashTable)
    • isPartialView

      boolean isPartialView()
      Description copied from class: ImmutableCollection
      Returns true if this immutable collection's implementation contains references to user-created objects that aren't accessible via this collection's methods. This is generally used to determine whether copyOf implementations should make an explicit copy to avoid memory leaks.
      Specified by:
      isPartialView in class ImmutableCollection<E>
    • count

      public int count(@CheckForNull Object element)
      Description copied from interface: Multiset
      Returns the number of occurrences of an element in this multiset (the count of the element). Note that for an Object.equals(java.lang.Object)-based multiset, this gives the same result as Collections.frequency(java.util.Collection<?>, java.lang.Object) (which would presumably perform more poorly).

      Note: the utility method Iterables.frequency(java.lang.Iterable<?>, java.lang.Object) generalizes this operation; it correctly delegates to this method when dealing with a multiset, but it can also accept any other iterable type.

      Parameters:
      element - the element to count occurrences of
      Returns:
      the number of occurrences of the element in this multiset; possibly zero but never negative
    • size

      public int size()
      Description copied from interface: Multiset
      Returns the total number of all occurrences of all elements in this multiset.

      Note: this method does not return the number of distinct elements in the multiset, which is given by entrySet().size().

      Specified by:
      size in interface Collection<E>
      Specified by:
      size in interface Multiset<E>
      Specified by:
      size in class AbstractCollection<E>
    • elementSet

      public ImmutableSet<E> elementSet()
      Description copied from interface: Multiset
      Returns the set of distinct elements contained in this multiset. The element set is backed by the same data as the multiset, so any change to either is immediately reflected in the other. The order of the elements in the element set is unspecified.

      If the element set supports any removal operations, these necessarily cause all occurrences of the removed element(s) to be removed from the multiset. Implementations are not expected to support the add operations, although this is possible.

      A common use for the element set is to find the number of distinct elements in the multiset: elementSet().size().

      Specified by:
      elementSet in interface Multiset<E>
      Specified by:
      elementSet in class ImmutableMultiset<E>
      Returns:
      a view of the set of distinct elements in this multiset
    • getEntry

      Multiset.Entry<E> getEntry(int index)
      Specified by:
      getEntry in class ImmutableMultiset<E>
    • hashCode

      public int hashCode()
      Description copied from interface: Multiset
      Returns the hash code for this multiset. This is defined as the sum of
      
       ((element == null) ? 0 : element.hashCode()) ^ count(element)
       

      over all distinct elements in the multiset. It follows that a multiset and its entry set always have the same hash code.

      Specified by:
      hashCode in interface Collection<E>
      Specified by:
      hashCode in interface Multiset<E>
      Overrides:
      hashCode in class ImmutableMultiset<E>
    • writeReplace

      Object writeReplace()
      Overrides:
      writeReplace in class ImmutableMultiset<E>