public class ReferenceLinkedOpenHashSet<K> extends AbstractReferenceSortedSet<K> implements Serializable, Cloneable, Hash
Instances of this class use a hash table to represent a set. The table is
enlarged as needed by doubling its size when new entries are created, but it is never made
smaller (even on a clear()). A family of trimming
methods lets you control the size of the table; this is particularly useful
if you reuse instances of this class.
Iterators generated by this set will enumerate elements in the same order in which they have been added to the set (addition of elements already present in the set does not change the iteration order). Note that this order has nothing in common with the natural order of the keys. The order is kept by means of a doubly linked list, represented via an array of longs parallel to the table.
This class implements the interface of a sorted set, so to allow easy
access of the iteration order: for instance, you can get the first element
in iteration order with first() without having to create an
iterator; however, this class partially violates the SortedSet
contract because all subset methods throw an exception and comparator() returns always null.
Additional methods, such as addAndMoveToFirst(), make it easy
to use instances of this class as a cache (e.g., with LRU policy).
The iterators provided by this class are type-specific list iterators, and can be started at any
element which is in the set (if the provided element
is not in the set, a NoSuchElementException exception will be thrown).
If, however, the provided element is not the first or last element in the
set, the first access to the list index will require linear time, as in the worst case
the entire set must be scanned in iteration order to retrieve the positional
index of the starting element. If you use just the methods of a type-specific BidirectionalIterator,
however, all operations will be performed in constant time.
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 |
|---|
ReferenceLinkedOpenHashSet()
Creates a new hash set with initial expected
Hash.DEFAULT_INITIAL_SIZE elements
and Hash.DEFAULT_LOAD_FACTOR as load factor. |
ReferenceLinkedOpenHashSet(Collection<? extends K> c)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given collection. |
ReferenceLinkedOpenHashSet(Collection<? extends K> c,
float f)
Creates a new hash set copying a given collection.
|
ReferenceLinkedOpenHashSet(int expected)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor. |
ReferenceLinkedOpenHashSet(int expected,
float f)
Creates a new hash set.
|
ReferenceLinkedOpenHashSet(K[] a)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying the elements of an array. |
ReferenceLinkedOpenHashSet(K[] a,
float f)
Creates a new hash set copying the elements of an array.
|
ReferenceLinkedOpenHashSet(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. |
ReferenceLinkedOpenHashSet(K[] a,
int offset,
int length,
float f)
Creates a new hash set and fills it with the elements of a given array.
|
ReferenceLinkedOpenHashSet(ObjectIterator<K> i)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by a type-specific iterator. |
ReferenceLinkedOpenHashSet(ObjectIterator<K> i,
float f)
Creates a new hash set using elements provided by a type-specific iterator.
|
ReferenceLinkedOpenHashSet(ReferenceCollection<? extends K> c)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given type-specific collection. |
ReferenceLinkedOpenHashSet(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 |
addAndMoveToFirst(K k)
Adds a key to the set; if the key is already present, it is moved to the first position of the iteration order.
|
boolean |
addAndMoveToLast(K k)
Adds a key to the set; if the key is already present, it is moved to the last position of the iteration order.
|
void |
clear() |
ReferenceLinkedOpenHashSet<K> |
clone()
Returns a deep copy of this set.
|
Comparator<? super K> |
comparator() |
boolean |
contains(Object k) |
K |
first()
Returns the first element of this set in iteration order.
|
int |
growthFactor()
Deprecated.
Since
fastutil 6.1.0, hash tables are doubled when they are too full. |
void |
growthFactor(int growthFactor)
Deprecated.
Since
fastutil 6.1.0, hash tables are doubled when they are too full. |
int |
hashCode()
Returns a hash code for this set.
|
ReferenceSortedSet<K> |
headSet(K to)
Returns a view of the portion of this sorted set whose elements are strictly less than
toElement. |
boolean |
isEmpty() |
ObjectListIterator<K> |
iterator()
Returns a type-specific iterator on the elements of this collection.
|
ObjectListIterator<K> |
iterator(K from)
Returns a type-specific list iterator on the elements in this set, starting from a given element of the set.
|
K |
last()
Returns the last element of this set in iteration order.
|
boolean |
rehash()
Deprecated.
A no-op.
|
boolean |
remove(Object k)
Removes an element from this set.
|
K |
removeFirst()
Removes the first key in iteration order.
|
K |
removeLast()
Removes the the last key in iteration order.
|
int |
size() |
ReferenceSortedSet<K> |
subSet(K from,
K to)
Returns a view of the portion of this sorted set whose elements range from
fromElement, inclusive, to toElement, exclusive. |
ReferenceSortedSet<K> |
tailSet(K from)
Returns a view of the portion of this sorted set whose elements are greater than or equal to
fromElement. |
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.
|
objectIteratorequalsaddAll, containsAll, removeAll, retainAll, toArray, toArray, toStringtoArraypublic ReferenceLinkedOpenHashSet(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 ReferenceLinkedOpenHashSet(int expected)
Hash.DEFAULT_LOAD_FACTOR as load factor.expected - the expected number of elements in the hash set.public ReferenceLinkedOpenHashSet()
Hash.DEFAULT_INITIAL_SIZE elements
and Hash.DEFAULT_LOAD_FACTOR as load factor.public ReferenceLinkedOpenHashSet(Collection<? extends K> c, float f)
c - a Collection to be copied into the new hash set.f - the load factor.public ReferenceLinkedOpenHashSet(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 ReferenceLinkedOpenHashSet(ReferenceCollection<? extends K> c, float f)
c - a type-specific collection to be copied into the new hash set.f - the load factor.public ReferenceLinkedOpenHashSet(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 ReferenceLinkedOpenHashSet(ObjectIterator<K> i, float f)
i - a type-specific iterator whose elements will fill the set.f - the load factor.public ReferenceLinkedOpenHashSet(ObjectIterator<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 ReferenceLinkedOpenHashSet(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 ReferenceLinkedOpenHashSet(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 ReferenceLinkedOpenHashSet(K[] a, float f)
a - an array to be copied into the new hash set.f - the load factor.public ReferenceLinkedOpenHashSet(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 boolean add(K k)
add in interface Collection<K>add in interface Set<K>add in class AbstractReferenceCollection<K>public boolean remove(Object k)
ReferenceSetNote that the corresponding method of the type-specific collection is rem().
This unfortunate situation is caused by the clash
with the similarly named index-based method in the List interface.
remove in interface ReferenceSet<K>remove in interface Collection<K>remove in interface Set<K>remove in class AbstractReferenceSet<K>Collection.remove(Object)public boolean contains(Object k)
contains in interface Collection<K>contains in interface Set<K>contains in class AbstractCollection<K>public K removeFirst()
NoSuchElementException - is this set is empty.public K removeLast()
NoSuchElementException - is this set is empty.public boolean addAndMoveToFirst(K k)
k - the key.public boolean addAndMoveToLast(K k)
k - the key.public void clear()
clear in interface Collection<K>clear in interface Set<K>clear in class AbstractCollection<K>public int size()
size in interface Collection<K>size in interface Set<K>size in class AbstractCollection<K>public boolean isEmpty()
isEmpty in interface Collection<K>isEmpty in interface Set<K>isEmpty in class AbstractReferenceCollection<K>@Deprecated public void growthFactor(int growthFactor)
fastutil 6.1.0, hash tables are doubled when they are too full.growthFactor - unused.@Deprecated public int growthFactor()
fastutil 6.1.0, hash tables are doubled when they are too full.growthFactor(int)public K first()
public K last()
public ReferenceSortedSet<K> tailSet(K from)
ReferenceSortedSetfromElement.
Note that this specification strengthens the one given in SortedSet.tailSet(Object).
tailSet in interface ReferenceSortedSet<K>tailSet in interface SortedSet<K>SortedSet.tailSet(Object)public ReferenceSortedSet<K> headSet(K to)
ReferenceSortedSettoElement.
Note that this specification strengthens the one given in SortedSet.headSet(Object).
headSet in interface ReferenceSortedSet<K>headSet in interface SortedSet<K>SortedSet.headSet(Object)public ReferenceSortedSet<K> subSet(K from, K to)
ReferenceSortedSetfromElement, inclusive, to toElement, exclusive.
Note that this specification strengthens the one given in SortedSet.subSet(Object,Object).
subSet in interface ReferenceSortedSet<K>subSet in interface SortedSet<K>SortedSet.subSet(Object,Object)public Comparator<? super K> comparator()
comparator in interface SortedSet<K>public ObjectListIterator<K> iterator(K from)
iterator in interface ReferenceSortedSet<K>from - an element to start from.IllegalArgumentException - if from does not belong to the set.public ObjectListIterator<K> iterator()
ReferenceCollectionNote that this specification strengthens the one given in
Iterable.iterator(), which was already
strengthened in the corresponding type-specific class,
but was weakened by the fact that this interface extends Collection.
iterator in interface ObjectIterable<K>iterator in interface ReferenceCollection<K>iterator in interface ReferenceSet<K>iterator in interface ReferenceSortedSet<K>iterator in interface Iterable<K>iterator in interface Collection<K>iterator in interface Set<K>iterator in class AbstractReferenceSortedSet<K>@Deprecated public boolean rehash()
If you need to reduce the table size to fit exactly
this set, use trim().
trim()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 ReferenceLinkedOpenHashSet<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.
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 Collection<K>hashCode in interface Set<K>hashCode in class AbstractReferenceSet<K>