public class IntOpenHashSet extends AbstractIntSet implements Serializable, 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>| Modifier and Type | Field and Description |
|---|---|
protected boolean |
containsNull
Whether this set contains the null key.
|
protected float |
f
The acceptable load factor.
|
protected int[] |
key
The array of keys.
|
protected int |
mask
The mask for wrapping a position counter.
|
protected int |
maxFill
Threshold after which we rehash.
|
protected int |
minN
We never resize below this threshold, which is the construction-time {#n}.
|
protected int |
n
The current table size.
|
protected int |
size
Number of entries in the set (including the null key, if present).
|
DEFAULT_GROWTH_FACTOR, DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR, FAST_LOAD_FACTOR, FREE, OCCUPIED, PRIMES, REMOVED, VERY_FAST_LOAD_FACTOR| Constructor and Description |
|---|
IntOpenHashSet()
Creates a new hash set with initial expected
Hash.DEFAULT_INITIAL_SIZE elements
and Hash.DEFAULT_LOAD_FACTOR as load factor. |
IntOpenHashSet(Collection<? extends Integer> c)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given collection. |
IntOpenHashSet(Collection<? extends Integer> c,
float f)
Creates a new hash set copying a given collection.
|
IntOpenHashSet(int expected)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor. |
IntOpenHashSet(int[] a)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying the elements of an array. |
IntOpenHashSet(int[] a,
float f)
Creates a new hash set copying the elements of an array.
|
IntOpenHashSet(int[] 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. |
IntOpenHashSet(int[] a,
int offset,
int length,
float f)
Creates a new hash set and fills it with the elements of a given array.
|
IntOpenHashSet(IntCollection c)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given type-specific collection. |
IntOpenHashSet(IntCollection c,
float f)
Creates a new hash set copying a given type-specific collection.
|
IntOpenHashSet(int expected,
float f)
Creates a new hash set.
|
IntOpenHashSet(IntIterator i)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by a type-specific iterator. |
IntOpenHashSet(IntIterator i,
float f)
Creates a new hash set using elements provided by a type-specific iterator.
|
IntOpenHashSet(Iterator<?> i)
Creates a new hash set with
Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by an iterator. |
IntOpenHashSet(Iterator<?> i,
float f)
Creates a new hash set using elements provided by an iterator.
|
| Modifier and Type | Method and Description |
|---|---|
boolean |
add(int k)
Ensures that this collection contains the specified element (optional operation).
|
boolean |
addAll(Collection<? extends Integer> c) |
boolean |
addAll(IntCollection c)
Adds all elements of the given type-specific collection to this collection.
|
void |
clear() |
IntOpenHashSet |
clone()
Returns a deep copy of this set.
|
boolean |
contains(int k)
Returns
true if this collection contains the specified element. |
int |
hashCode()
Returns a hash code for this set.
|
boolean |
isEmpty() |
IntIterator |
iterator()
Returns a type-specific iterator on the elements of this collection.
|
protected void |
rehash(int newN)
Rehashes the set.
|
boolean |
remove(int k)
Removes an element from this set.
|
protected void |
shiftKeys(int pos)
Shifts left entries with the specified hash code, starting at the specified position,
and empties the resulting free entry.
|
int |
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, remadd, contains, containsAll, remove, removeAll, retainAll, toArray, toIntArray, toIntArray, toStringcontainsAll, removeAll, retainAll, toArray, toArrayfinalize, getClass, notify, notifyAll, wait, wait, waitcontainsAll, removeAll, removeIf, removeIf, retainAll, toArray, toIntArray, toIntArrayforEach, forEachcontainsAll, removeAll, retainAll, spliterator, toArray, toArrayparallelStream, streamprotected transient int[] key
protected transient int mask
protected transient boolean containsNull
protected transient int n
protected transient int maxFill
f.protected final transient int minN
protected int size
protected final float f
public IntOpenHashSet(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 IntOpenHashSet(int expected)
Hash.DEFAULT_LOAD_FACTOR as load factor.expected - the expected number of elements in the hash set.public IntOpenHashSet()
Hash.DEFAULT_INITIAL_SIZE elements
and Hash.DEFAULT_LOAD_FACTOR as load factor.public IntOpenHashSet(Collection<? extends Integer> c, float f)
c - a Collection to be copied into the new hash set.f - the load factor.public IntOpenHashSet(Collection<? extends Integer> c)
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given collection.c - a Collection to be copied into the new hash set.public IntOpenHashSet(IntCollection c, float f)
c - a type-specific collection to be copied into the new hash set.f - the load factor.public IntOpenHashSet(IntCollection 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 IntOpenHashSet(IntIterator i, float f)
i - a type-specific iterator whose elements will fill the set.f - the load factor.public IntOpenHashSet(IntIterator 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 IntOpenHashSet(Iterator<?> i, float f)
i - an iterator whose elements will fill the set.f - the load factor.public IntOpenHashSet(Iterator<?> i)
Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by an iterator.i - an iterator whose elements will fill the set.public IntOpenHashSet(int[] 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 IntOpenHashSet(int[] 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 IntOpenHashSet(int[] a,
float f)
a - an array to be copied into the new hash set.f - the load factor.public IntOpenHashSet(int[] 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 addAll(IntCollection c)
IntCollectionaddAll in interface IntCollectionaddAll in class AbstractIntCollectionc - a type-specific collection.true if this collection changed as a result of the call.Collection.addAll(Collection)public boolean addAll(Collection<? extends Integer> c)
addAll in interface Collection<Integer>addAll in interface Set<Integer>addAll in class AbstractCollection<Integer>public boolean add(int k)
AbstractIntCollectionThis implementation always throws an UnsupportedOperationException.
add in interface IntCollectionadd in class AbstractIntCollectionCollection.add(Object)protected final void shiftKeys(int pos)
pos - a starting position.public boolean remove(int k)
AbstractIntSetNote that the corresponding method of a type-specific collection is rem().
This unfortunate situation is caused by the clash
with the similarly named index-based method in the List interface.
Delegates to the type-specific rem() method
implemented by type-specific abstract Collection superclass.
remove in interface IntSetremove in class AbstractIntSetCollection.remove(Object)public boolean contains(int k)
AbstractIntCollectiontrue if this collection contains the specified element.
This implementation iterates over the elements in the collection, looking for the specified element.
contains in interface IntCollectioncontains in class AbstractIntCollectionCollection.contains(Object)public void clear()
clear in interface Collection<Integer>clear in interface Set<Integer>clear in class AbstractCollection<Integer>public int size()
size in interface Collection<Integer>size in interface Set<Integer>size in class AbstractCollection<Integer>public boolean isEmpty()
isEmpty in interface Collection<Integer>isEmpty in interface Set<Integer>isEmpty in class AbstractCollection<Integer>public IntIterator iterator()
IntCollectionNote 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 IntCollectioniterator in interface IntIterableiterator in interface IntSetiterator in interface Iterable<Integer>iterator in interface Collection<Integer>iterator in interface Set<Integer>iterator in class AbstractIntSetIterable.iterator()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()protected void rehash(int newN)
This method implements the basic rehashing strategy, and may be overriden by subclasses implementing different rehashing strategies (e.g., disk-based rehashing). However, you should not override this method unless you understand the internal workings of this class.
newN - the new sizepublic IntOpenHashSet 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<Integer>hashCode in interface Set<Integer>hashCode in class AbstractIntSetCopyright © 2020. All rights reserved.