public class ObjectOpenHashBigSet<K> extends AbstractObjectSet<K> implements Serializable, Cloneable, Hash, Size64
Instances of this class use a hash table to represent a big set: the number of elements in the set is limited only by the amount of core memory. The table (backed by a big array) 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, 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.
The methods of this class are about 30% slower than those of the corresponding non-big set.
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 |
---|
ObjectOpenHashBigSet()
Creates a new hash big set with initial expected
Hash.DEFAULT_INITIAL_SIZE elements and Hash.DEFAULT_LOAD_FACTOR as load factor. |
ObjectOpenHashBigSet(Collection<? extends K> c)
Creates a new hash big set with
Hash.DEFAULT_LOAD_FACTOR as load factor copying a given collection. |
ObjectOpenHashBigSet(Collection<? extends K> c,
float f)
Creates a new hash big set copying a given collection.
|
ObjectOpenHashBigSet(Iterator<? extends K> i)
Creates a new hash big set with
Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by a type-specific iterator. |
ObjectOpenHashBigSet(Iterator<? extends K> i,
float f)
Creates a new hash big set using elements provided by a type-specific iterator.
|
ObjectOpenHashBigSet(K[] a)
Creates a new hash big set with
Hash.DEFAULT_LOAD_FACTOR as load factor copying the elements of an array. |
ObjectOpenHashBigSet(K[] a,
float f)
Creates a new hash big set copying the elements of an array.
|
ObjectOpenHashBigSet(K[] a,
int offset,
int length)
Creates a new hash big set with
Hash.DEFAULT_LOAD_FACTOR as load factor and fills it with the elements of a given array. |
ObjectOpenHashBigSet(K[] a,
int offset,
int length,
float f)
Creates a new hash big set and fills it with the elements of a given array.
|
ObjectOpenHashBigSet(long expected)
Creates a new hash big set with
Hash.DEFAULT_LOAD_FACTOR as load factor. |
ObjectOpenHashBigSet(long expected,
float f)
Creates a new hash big set.
|
ObjectOpenHashBigSet(ObjectCollection<? extends K> c)
Creates a new hash big set with
Hash.DEFAULT_LOAD_FACTOR as load factor copying a given type-specific collection. |
ObjectOpenHashBigSet(ObjectCollection<? extends K> c,
float f)
Creates a new hash big set copying a given type-specific collection.
|
Modifier and Type | Method and Description |
---|---|
boolean |
add(K k) |
boolean |
addAll(Collection<? extends K> c)
Adds all elements of the given collection to this collection.
|
void |
clear() |
ObjectOpenHashBigSet<K> |
clone()
Returns a deep copy of this big set.
|
boolean |
contains(Object k) |
K |
get(Object k)
Returns the element of this set that is equal to the given key, or
null . |
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.
|
boolean |
rehash()
Deprecated.
A no-op.
|
boolean |
remove(Object k)
Removes an element from this set.
|
int |
size()
Deprecated.
|
long |
size64()
Returns the size of this data structure as a long.
|
boolean |
trim()
Rehashes this set, making the table as small as possible.
|
boolean |
trim(long n)
Rehashes this set if the table is too large.
|
equals
containsAll, objectIterator, removeAll, retainAll, toArray, toArray, toString
objectIterator, toArray
containsAll, removeAll, retainAll, spliterator, toArray, toArray
parallelStream, removeIf, stream
public ObjectOpenHashBigSet(long 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 set.f
- the load factor.public ObjectOpenHashBigSet(long expected)
Hash.DEFAULT_LOAD_FACTOR
as load factor.expected
- the expected number of elements in the hash big set.public ObjectOpenHashBigSet()
Hash.DEFAULT_INITIAL_SIZE
elements and Hash.DEFAULT_LOAD_FACTOR
as load factor.public ObjectOpenHashBigSet(Collection<? extends K> c, float f)
c
- a Collection
to be copied into the new hash big set.f
- the load factor.public ObjectOpenHashBigSet(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 big set.public ObjectOpenHashBigSet(ObjectCollection<? extends K> c, float f)
c
- a type-specific collection to be copied into the new hash big set.f
- the load factor.public ObjectOpenHashBigSet(ObjectCollection<? 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 big set.public ObjectOpenHashBigSet(Iterator<? extends K> i, float f)
i
- a type-specific iterator whose elements will fill the new hash big set.f
- the load factor.public ObjectOpenHashBigSet(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 new hash big set.public ObjectOpenHashBigSet(K[] a, int offset, int length, float f)
a
- an array whose elements will be used to fill the new hash big set.offset
- the first element to use.length
- the number of elements to use.f
- the load factor.public ObjectOpenHashBigSet(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 new hash big set.offset
- the first element to use.length
- the number of elements to use.public ObjectOpenHashBigSet(K[] a, float f)
a
- an array to be copied into the new hash big set.f
- the load factor.public ObjectOpenHashBigSet(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 big set.public boolean addAll(Collection<? extends K> c)
addAll
in interface Collection<K>
addAll
in interface Set<K>
addAll
in class AbstractObjectCollection<K>
c
- a collection.true
if this collection changed as a result of the call.public boolean add(K k)
add
in interface Collection<K>
add
in interface Set<K>
add
in class AbstractObjectCollection<K>
public boolean remove(Object k)
ObjectSet
Note 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 ObjectSet<K>
remove
in interface Collection<K>
remove
in interface Set<K>
remove
in class AbstractObjectSet<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 get(Object k)
null
.null
.public void clear()
clear
in interface Collection<K>
clear
in interface Set<K>
clear
in class AbstractCollection<K>
public ObjectIterator<K> iterator()
ObjectCollection
Note 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 ObjectCollection<K>
iterator
in interface ObjectIterable<K>
iterator
in interface ObjectSet<K>
iterator
in interface Iterable<K>
iterator
in interface Collection<K>
iterator
in interface Set<K>
iterator
in class AbstractObjectSet<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(long)
public boolean trim(long 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.
size64()
)
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()
@Deprecated public int size()
Size64
Integer.MAX_VALUE
.size
in interface Size64
size
in interface Collection<K>
size
in interface Set<K>
size
in class AbstractCollection<K>
Integer.MAX_VALUE
.Collection.size()
public long size64()
Size64
public boolean isEmpty()
isEmpty
in interface Collection<K>
isEmpty
in interface Set<K>
isEmpty
in class AbstractObjectCollection<K>
public ObjectOpenHashBigSet<K> clone()
This method performs a deep copy of this big 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 AbstractObjectSet<K>