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, 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.
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)
Ensures that this collection contains the specified element (optional
operation).
|
boolean |
addAll(Collection<? extends K> c)
Adds all of the elements in the specified collection to this collection
(optional operation).
|
K |
addOrGet(K k)
Add a random element if not present, get the existing value if already
present.
|
void |
clear()
Removes all of the elements from this collection (optional operation).
|
ObjectOpenHashBigSet<K> |
clone()
Returns a deep copy of this big set.
|
boolean |
contains(Object k)
Returns true if this collection contains the specified element.
|
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()
Returns true if this collection contains no elements.
|
ObjectIterator<K> |
iterator()
Returns an iterator over the elements contained in this collection.
|
boolean |
remove(Object k)
Removes a single instance of the specified element from this
collection, if it is present (optional operation).
|
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.
|
equalstoStringcontainsAll, removeAll, retainAll, toArray, toArraycontainsAll, removeAll, retainAll, spliterator, toArray, toArrayparallelStream, removeIf, streampublic 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)
java.util.AbstractCollectionThis implementation iterates over the specified collection, and adds each object returned by the iterator to this collection, in turn.
Note that this implementation will throw an UnsupportedOperationException unless add is overridden (assuming the specified collection is non-empty).
addAll in interface Collection<K>addAll in interface Set<K>addAll in class AbstractCollection<K>c - collection containing elements to be added to this collectionAbstractCollection.add(Object)public boolean add(K k)
java.util.AbstractCollectionCollections that support this operation may place limitations on what elements may be added to this collection. In particular, some collections will refuse to add null elements, and others will impose restrictions on the type of elements that may be added. Collection classes should clearly specify in their documentation any restrictions on what elements may be added.
If a collection refuses to add a particular element for any reason other than that it already contains the element, it must throw an exception (rather than returning false). This preserves the invariant that a collection always contains the specified element after this call returns.
This implementation always throws an UnsupportedOperationException.
add in interface Collection<K>add in interface Set<K>add in class AbstractCollection<K>k - element whose presence in this collection is to be ensuredpublic K addOrGet(K k)
K exist = set.get(k);
if (exist == null) {
set.add(k);
exist = k;
}
public boolean remove(Object k)
java.util.AbstractCollectionThis implementation iterates over the collection looking for the specified element. If it finds the element, it removes the element from the collection using the iterator's remove method.
Note that this implementation throws an UnsupportedOperationException if the iterator returned by this collection's iterator method does not implement the remove method and this collection contains the specified object.
remove in interface Collection<K>remove in interface Set<K>remove in class AbstractCollection<K>k - element to be removed from this collection, if presentpublic boolean contains(Object k)
java.util.AbstractCollectionThis implementation iterates over the elements in the collection, checking each element in turn for equality with the specified element.
contains in interface Collection<K>contains in interface Set<K>contains in class AbstractCollection<K>k - element whose presence in this collection is to be testedpublic K get(Object k)
null.null.public void clear()
This implementation iterates over this collection, removing each element using the Iterator.remove operation. Most implementations will probably choose to override this method for efficiency.
Note that this implementation will throw an UnsupportedOperationException if the iterator returned by this collection's iterator method does not implement the remove method and this collection is non-empty.
To increase object reuse, this method does not change the table size. If
you want to reduce the table size, you must use trim(long).
clear in interface Collection<K>clear in interface Set<K>clear in class AbstractCollection<K>public ObjectIterator<K> iterator()
java.util.AbstractCollectioniterator 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>Iterable.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(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()
java.util.Collectionsize in interface Size64size in interface Collection<K>size in interface Set<K>size in class AbstractCollection<K>Collection.size()public long size64()
Size64public boolean isEmpty()
java.util.AbstractCollectionThis implementation returns size() == 0.
isEmpty in interface Collection<K>isEmpty in interface Set<K>isEmpty in class AbstractCollection<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>Object.equals(java.lang.Object),
System.identityHashCode(java.lang.Object)