Scala Library
scala.collection.mutable

class HashSet
[source: scala/collection/mutable/HashSet.scala]
@serializable

class HashSet[A]
extends Set[A] with GenericSetTemplate[A, HashSet] with SetLike[A, HashSet[A]] with FlatHashTable[A]
This class implements mutable sets using a hashtable.
Author
Matthias Zenger
Martin Odersky
Version
2.0, 31/12/2006
Since
1
Values and Variables inherited from FlatHashTable
table, tableSize, threshold
Method Summary
def += (elem : A) : HashSet[A]
Adds a new element to the set.
def -= (elem : A) : HashSet[A]
Removes a single element from a set.
override def add (elem : A) : Boolean
Adds a new element to the set.
override def clear : Unit
Removes all elements from the set. After this operation is completed, the set will be empty.
override def clone : Set[A]
This method creates and returns a copy of the receiver object.
override def companion : GenericCompanion[HashSet]
The factory companion object that builds instances of class CC
def contains (elem : A) : Boolean
Checks if this set contains element elem.
override def foreach [U](f : (A) => U) : Unit
Apply a function f to all elements of this iterable object.
override def remove (elem : A) : Boolean
Removes a single element from a set.
override def size : Int
The number of elements in this collection
Methods inherited from FlatHashTable
loadFactor, loadFactorDenum, initialSize, findEntry, containsEntry, addEntry, removeEntry, iterator, elemHashCode, improve, index, clearTable
Methods inherited from SetLike
newBuilder, update, retain, result, +, +, ++, ++, -, -, --, --, <<
Methods inherited from Shrinkable
-=, --=, --=
Methods inherited from Builder
sizeHint, mapResult
Methods inherited from Growable
+=, ++=, ++=
Methods inherited from SetLike
isEmpty, apply, intersect, &, **, union, |, diff, &~, subsetOf, stringPrefix, toString, hashCode, equals
Methods inherited from GenericSetTemplate
empty
Methods inherited from Function1
compose, andThen
Methods inherited from IterableLike
thisCollection, toCollection, elements, forall, exists, find, foldRight, reduceRight, toIterable, head, take, slice, takeWhile, takeRight, dropRight, copyToArray, zip, zipAll, zipWithIndex, sameElements, toStream, canEqual, view, view, first, firstOption, projection
Methods inherited from GenericTraversableTemplate
genericBuilder, unzip, flatten, transpose
Methods inherited from TraversableLike
repr, nonEmpty, hasDefiniteSize, ++, ++, map, flatMap, filter, filterNot, partialMap, remove, partition, groupBy, count, foldLeft, /:, :\, reduceLeft, reduceLeftOption, reduceRightOption, sum, product, min, max, headOption, tail, last, lastOption, init, drop, dropWhile, span, splitAt, copyToBuffer, copyToArray, toArray, toList, toSeq, toIndexedSeq, toSet, mkString, mkString, mkString, addString, addString, addString, withFilter
Methods inherited from AnyRef
getClass, notify, notifyAll, wait, wait, wait, finalize, ==, !=, eq, ne, synchronized
Methods inherited from Any
==, !=, isInstanceOf, asInstanceOf
Method Details
override def companion : GenericCompanion[HashSet]
The factory companion object that builds instances of class CC
Overrides
Set.companion
override def size : Int
The number of elements in this collection
def contains(elem : A) : Boolean
Checks if this set contains element elem.
Parameters
elem - the element to check for membership.
Returns
true iff elem is contained in this set.
def +=(elem : A) : HashSet[A]
Adds a new element to the set.
Parameters
elem - the element to be added
Overrides
SetLike.+=
def -=(elem : A) : HashSet[A]
Removes a single element from a set.
Parameters
elem - The element to be removed.
Overrides
SetLike.-=
override def add(elem : A) : Boolean
Adds a new element to the set.
Parameters
elem - the element to be added
Returns
true if the element was not yet present in the set.
Overrides
SetLike.add
override def remove(elem : A) : Boolean
Removes a single element from a set.
Parameters
elem - The element to be removed.
Returns
true if the element was already present in the set.
Overrides
SetLike.remove
override def clear : Unit
Removes all elements from the set. After this operation is completed, the set will be empty.
Overrides
SetLike.clear
override def foreach[U](f : (A) => U) : Unit
Apply a function f to all elements of this iterable object.
Parameters
f - A function that is applied for its side-effect to every element. The result (of arbitrary type U) of function `f` is discarded.
Notes
This method underlies the implementation of most other bulk operations. Implementing `foreach` with `iterator` is often suboptimal. So `foreach` should be overridden in concrete collection classes if a more efficient implementation is available.
override def clone : Set[A]
This method creates and returns a copy of the receiver object.

The default implementation of the clone method is platform dependent.

Returns
a copy of the receiver object.

Overrides
SetLike.clone
Scala Library