public class ReferenceOpenHashSet<K> extends AbstractReferenceSet<K> implements java.io.Serializable, java.lang.Cloneable, Hash
Instances of this class use a hash table to represent a set. 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 sets 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.
Hash
,
HashCommon
,
Serialized FormHash.Strategy<K>
DEFAULT_GROWTH_FACTOR, DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR, FAST_LOAD_FACTOR, FREE, OCCUPIED, PRIMES, REMOVED, VERY_FAST_LOAD_FACTOR
Constructor and Description |
---|
ReferenceOpenHashSet()
Creates a new hash set with initial expected
Hash.DEFAULT_INITIAL_SIZE elements
and Hash.DEFAULT_LOAD_FACTOR as load factor. |
ReferenceOpenHashSet(java.util.Collection<? extends K> c)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given collection. |
ReferenceOpenHashSet(java.util.Collection<? extends K> c,
float f)
Creates a new hash set copying a given collection.
|
ReferenceOpenHashSet(int expected)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor. |
ReferenceOpenHashSet(int expected,
float f)
Creates a new hash set.
|
ReferenceOpenHashSet(java.util.Iterator<? extends K> i)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by a type-specific iterator. |
ReferenceOpenHashSet(java.util.Iterator<? extends K> i,
float f)
Creates a new hash set using elements provided by a type-specific iterator.
|
ReferenceOpenHashSet(K[] a)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying the elements of an array. |
ReferenceOpenHashSet(K[] a,
float f)
Creates a new hash set copying the elements of an array.
|
ReferenceOpenHashSet(K[] a,
int offset,
int length)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor and fills it with the elements of a given array. |
ReferenceOpenHashSet(K[] a,
int offset,
int length,
float f)
Creates a new hash set and fills it with the elements of a given array.
|
ReferenceOpenHashSet(ReferenceCollection<? extends K> c)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given type-specific collection. |
ReferenceOpenHashSet(ReferenceCollection<? extends K> c,
float f)
Creates a new hash set copying a given type-specific collection.
|
Modifier and Type | Method and Description |
---|---|
boolean |
add(K k) |
boolean |
addAll(java.util.Collection<? extends K> c) |
void |
clear() |
ReferenceOpenHashSet<K> |
clone()
Returns a deep copy of this set.
|
boolean |
contains(java.lang.Object k) |
void |
forEach(java.util.function.Consumer<? super K> action) |
int |
hashCode()
Returns a hash code for this set.
|
boolean |
isEmpty() |
ObjectIterator<K> |
iterator()
Returns a type-specific iterator on the elements of this collection.
|
static <K> ReferenceOpenHashSet<K> |
of()
Creates a new empty hash set.
|
static <K> ReferenceOpenHashSet<K> |
of(K... a)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
using a list of elements. |
static <K> ReferenceOpenHashSet<K> |
of(K e)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
using the given element. |
static <K> ReferenceOpenHashSet<K> |
of(K e0,
K e1)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
using the elements given. |
static <K> ReferenceOpenHashSet<K> |
of(K e0,
K e1,
K e2)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
using the elements given. |
boolean |
remove(java.lang.Object k) |
int |
size() |
ObjectSpliterator<K> |
spliterator()
Returns a type-specific spliterator on the elements of this set.
|
static <K> java.util.stream.Collector<K,?,ReferenceOpenHashSet<K>> |
toSet()
Returns a
Collector that collects a Stream 's elements into a new hash set. |
static <K> java.util.stream.Collector<K,?,ReferenceOpenHashSet<K>> |
toSetWithExpectedSize(int expectedSize)
Returns a
Collector that collects a Stream 's elements into a new hash set, potentially pre-allocated to handle the given size. |
boolean |
trim()
Rehashes this set, making the table as small as possible.
|
boolean |
trim(int n)
Rehashes this set if the table is too large.
|
equals
toString
public ReferenceOpenHashSet(int expected, float f)
The actual table size will be the least power of two greater than expected
/f
.
expected
- the expected number of elements in the hash set.f
- the load factor.public ReferenceOpenHashSet(int expected)
Hash.DEFAULT_LOAD_FACTOR
as load factor.expected
- the expected number of elements in the hash set.public ReferenceOpenHashSet()
Hash.DEFAULT_INITIAL_SIZE
elements
and Hash.DEFAULT_LOAD_FACTOR
as load factor.public ReferenceOpenHashSet(java.util.Collection<? extends K> c, float f)
c
- a Collection
to be copied into the new hash set.f
- the load factor.public ReferenceOpenHashSet(java.util.Collection<? extends K> c)
Hash.DEFAULT_LOAD_FACTOR
as load factor
copying a given collection.c
- a Collection
to be copied into the new hash set.public ReferenceOpenHashSet(ReferenceCollection<? extends K> c, float f)
c
- a type-specific collection to be copied into the new hash set.f
- the load factor.public ReferenceOpenHashSet(ReferenceCollection<? extends K> c)
Hash.DEFAULT_LOAD_FACTOR
as load factor
copying a given type-specific collection.c
- a type-specific collection to be copied into the new hash set.public ReferenceOpenHashSet(java.util.Iterator<? extends K> i, float f)
i
- a type-specific iterator whose elements will fill the set.f
- the load factor.public ReferenceOpenHashSet(java.util.Iterator<? extends K> i)
Hash.DEFAULT_LOAD_FACTOR
as load factor using elements provided by a type-specific iterator.i
- a type-specific iterator whose elements will fill the set.public ReferenceOpenHashSet(K[] a, int offset, int length, float f)
a
- an array whose elements will be used to fill the set.offset
- the first element to use.length
- the number of elements to use.f
- the load factor.public ReferenceOpenHashSet(K[] a, int offset, int length)
Hash.DEFAULT_LOAD_FACTOR
as load factor and fills it with the elements of a given array.a
- an array whose elements will be used to fill the set.offset
- the first element to use.length
- the number of elements to use.public ReferenceOpenHashSet(K[] a, float f)
a
- an array to be copied into the new hash set.f
- the load factor.public ReferenceOpenHashSet(K[] a)
Hash.DEFAULT_LOAD_FACTOR
as load factor
copying the elements of an array.a
- an array to be copied into the new hash set.public static <K> ReferenceOpenHashSet<K> of()
of
in interface ReferenceSet<K>
public static <K> ReferenceOpenHashSet<K> of(K e)
Hash.DEFAULT_LOAD_FACTOR
as load factor
using the given element.of
in interface ReferenceSet<K>
e
- the element that the returned set will contain.Hash.DEFAULT_LOAD_FACTOR
as load factor containing e
.public static <K> ReferenceOpenHashSet<K> of(K e0, K e1)
Hash.DEFAULT_LOAD_FACTOR
as load factor
using the elements given.of
in interface ReferenceSet<K>
e0
- the first element.e1
- the second element.Hash.DEFAULT_LOAD_FACTOR
as load factor containing e0
and e1
.java.lang.IllegalArgumentException
- if there were duplicate entries.public static <K> ReferenceOpenHashSet<K> of(K e0, K e1, K e2)
Hash.DEFAULT_LOAD_FACTOR
as load factor
using the elements given.of
in interface ReferenceSet<K>
e0
- the first element.e1
- the second element.e2
- the third element.Hash.DEFAULT_LOAD_FACTOR
as load factor containing e0
, e1
, and e2
.java.lang.IllegalArgumentException
- if there were duplicate entries.@SafeVarargs public static <K> ReferenceOpenHashSet<K> of(K... a)
Hash.DEFAULT_LOAD_FACTOR
as load factor
using a list of elements.of
in interface ReferenceSet<K>
a
- a list of elements that will be used to initialize the new hash set.Hash.DEFAULT_LOAD_FACTOR
as load factor containing the elements of a
.java.lang.IllegalArgumentException
- if a duplicate entry was encountered.public static <K> java.util.stream.Collector<K,?,ReferenceOpenHashSet<K>> toSet()
Collector
that collects a Stream
's elements into a new hash set.public static <K> java.util.stream.Collector<K,?,ReferenceOpenHashSet<K>> toSetWithExpectedSize(int expectedSize)
Collector
that collects a Stream
's elements into a new hash set, potentially pre-allocated to handle the given size.public boolean addAll(java.util.Collection<? extends K> c)
public boolean add(K k)
public boolean remove(java.lang.Object k)
public boolean contains(java.lang.Object k)
public void clear()
public int size()
public boolean isEmpty()
public ObjectIterator<K> iterator()
ReferenceCollection
iterator
in interface ObjectIterable<K>
iterator
in interface ReferenceCollection<K>
iterator
in interface ReferenceSet<K>
iterator
in interface java.lang.Iterable<K>
iterator
in interface java.util.Collection<K>
iterator
in interface java.util.Set<K>
iterator
in class AbstractReferenceSet<K>
Iterable.iterator()
public ObjectSpliterator<K> spliterator()
ReferenceSet
Set spliterators must report at least Spliterator.DISTINCT
.
See Set.spliterator()
for more documentation on the requirements
of the returned spliterator.
spliterator
in interface ObjectIterable<K>
spliterator
in interface ReferenceCollection<K>
spliterator
in interface ReferenceSet<K>
spliterator
in interface java.lang.Iterable<K>
spliterator
in interface java.util.Collection<K>
spliterator
in interface java.util.Set<K>
public void forEach(java.util.function.Consumer<? super K> action)
forEach
in interface java.lang.Iterable<K>
public boolean trim()
This method rehashes the table to the smallest size satisfying the load factor. It can be used when the set will not be changed anymore, so to optimize access speed and size.
If the table size is already the minimum possible, this method does nothing.
trim(int)
public boolean trim(int n)
Let N be the smallest table size that can hold
max(n,
entries, still satisfying the load factor. If the current
table size is smaller than or equal to N, this method does
nothing. Otherwise, it rehashes this set in a table of size
N.
size()
)
This method is useful when reusing sets. Clearing a set leaves the table size untouched. If you are reusing a set many times, you can call this method with a typical size to avoid keeping around a very large table just because of a few large transient sets.
n
- the threshold for the trimming.trim()
public ReferenceOpenHashSet<K> clone()
This method performs a deep copy of this hash set; the data stored in the set, however, is not cloned. Note that this makes a difference only for object keys.
clone
in class java.lang.Object
public int hashCode()
equals()
is not overriden, it is important
that the value returned by this method is the same value as
the one returned by the overriden method.hashCode
in interface java.util.Collection<K>
hashCode
in interface java.util.Set<K>
hashCode
in class AbstractReferenceSet<K>