Class ByteLinkedOpenCustomHashSet
- All Implemented Interfaces:
ByteBidirectionalIterable,ByteCollection,ByteIterable,ByteSet,ByteSortedSet,Hash,Serializable,Cloneable,Iterable<Byte>,Collection<Byte>,SequencedCollection<Byte>,SequencedSet<Byte>,Set<Byte>,SortedSet<Byte>
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.
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.
- See Also:
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Nested Class Summary
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.Hash
Hash.Strategy<K> -
Field Summary
Fields inherited from interface it.unimi.dsi.fastutil.Hash
DEFAULT_GROWTH_FACTOR, DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR, FAST_LOAD_FACTOR, FREE, OCCUPIED, PRIMES, REMOVED, VERY_FAST_LOAD_FACTOR -
Constructor Summary
ConstructorsConstructorDescriptionByteLinkedOpenCustomHashSet(byte[] a, float f, ByteHash.Strategy strategy) Creates a new hash set copying the elements of an array.ByteLinkedOpenCustomHashSet(byte[] a, int offset, int length, float f, ByteHash.Strategy strategy) Creates a new hash set and fills it with the elements of a given array.ByteLinkedOpenCustomHashSet(byte[] a, int offset, int length, ByteHash.Strategy strategy) Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor and fills it with the elements of a given array.ByteLinkedOpenCustomHashSet(byte[] a, ByteHash.Strategy strategy) Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor copying the elements of an array.ByteLinkedOpenCustomHashSet(int expected, float f, ByteHash.Strategy strategy) Creates a new hash set.ByteLinkedOpenCustomHashSet(int expected, ByteHash.Strategy strategy) Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor.ByteLinkedOpenCustomHashSet(ByteCollection c, float f, ByteHash.Strategy strategy) Creates a new hash set copying a given type-specific collection.ByteLinkedOpenCustomHashSet(ByteCollection c, ByteHash.Strategy strategy) Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor copying a given type-specific collection.ByteLinkedOpenCustomHashSet(ByteHash.Strategy strategy) Creates a new hash set with initial expectedHash.DEFAULT_INITIAL_SIZEelements andHash.DEFAULT_LOAD_FACTORas load factor.ByteLinkedOpenCustomHashSet(ByteIterator i, float f, ByteHash.Strategy strategy) Creates a new hash set using elements provided by a type-specific iterator.ByteLinkedOpenCustomHashSet(ByteIterator i, ByteHash.Strategy strategy) Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor using elements provided by a type-specific iterator.ByteLinkedOpenCustomHashSet(Collection<? extends Byte> c, float f, ByteHash.Strategy strategy) Creates a new hash set copying a given collection.ByteLinkedOpenCustomHashSet(Collection<? extends Byte> c, ByteHash.Strategy strategy) Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor copying a given collection.ByteLinkedOpenCustomHashSet(Iterator<?> i, float f, ByteHash.Strategy strategy) Creates a new hash set using elements provided by an iterator.ByteLinkedOpenCustomHashSet(Iterator<?> i, ByteHash.Strategy strategy) Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor using elements provided by an iterator. -
Method Summary
Modifier and TypeMethodDescriptionbooleanadd(byte k) Ensures that this collection contains the specified element (optional operation).booleanAdds all elements of the given type-specific collection to this collection.booleanaddAll(Collection<? extends Byte> c) booleanaddAndMoveToFirst(byte k) Adds a key to the set; if the key is already present, it is moved to the first position of the iteration order.booleanaddAndMoveToLast(byte k) Adds a key to the set; if the key is already present, it is moved to the last position of the iteration order.voidclear()Removes all elements from this set.clone()Returns a deep copy of this set.booleancontains(byte k) Returnstrueif this collection contains the specified element.voidensureCapacity(int capacity) Ensures that this set can hold a certain number of elements without rehashing.byteReturns the first element of this set in iteration order.voidforEach(ByteConsumer action) Performs the given action for each element of this type-specificIterableuntil all elements have been processed or the action throws an exception.inthashCode()Returns a hash code for this set.headSet(byte to) Returns a view of the portion of this sorted set whose elements are strictly less thantoElement.booleanisEmpty()iterator()Returns a type-specific list iterator on the elements in this set, starting from the first element.iterator(byte from) Returns a type-specific list iterator on the elements in this set, starting from a given element of the set.bytelastByte()Returns the last element of this set in iteration order.booleanremove(byte k) Removes an element from this set.byteRemoves the first key in iteration order.byteRemoves the the last key in iteration order.intsize()Returns a type-specific spliterator on the elements of this collection.strategy()Returns the hashing strategy.subSet(byte from, byte to) Returns a view of the portion of this sorted set whose elements range fromfromElement, inclusive, totoElement, exclusive.tailSet(byte from) Returns a view of the portion of this sorted set whose elements are greater than or equal tofromElement.booleantrim()Rehashes this set, making the table as small as possible.booleantrim(int n) Rehashes this set if the table is too large.Methods inherited from class it.unimi.dsi.fastutil.bytes.AbstractByteSet
equals, remMethods inherited from class it.unimi.dsi.fastutil.bytes.AbstractByteCollection
add, contains, containsAll, containsAll, remove, removeAll, removeAll, retainAll, retainAll, toArray, toByteArray, toByteArray, toStringMethods inherited from class java.util.AbstractCollection
toArray, toArrayMethods inherited from interface it.unimi.dsi.fastutil.bytes.ByteCollection
containsAll, intIterator, intParallelStream, intSpliterator, intStream, parallelStream, removeAll, removeIf, removeIf, removeIf, retainAll, stream, toArray, toByteArray, toByteArrayMethods inherited from interface it.unimi.dsi.fastutil.bytes.ByteIterable
forEach, forEachMethods inherited from interface it.unimi.dsi.fastutil.bytes.ByteSortedSet
first, headSet, last, subSet, tailSetMethods inherited from interface java.util.Collection
toArrayMethods inherited from interface java.util.Set
add, contains, containsAll, equals, remove, removeAll, retainAll, toArray, toArrayMethods inherited from interface java.util.SortedSet
addFirst, addLast, getFirst, getLast, removeFirst, removeLast, reversed
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Constructor Details
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ByteLinkedOpenCustomHashSet
Creates a new hash set.The actual table size will be the least power of two greater than
expected/f.- Parameters:
expected- the expected number of elements in the hash set.f- the load factor.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor.- Parameters:
expected- the expected number of elements in the hash set.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set with initial expectedHash.DEFAULT_INITIAL_SIZEelements andHash.DEFAULT_LOAD_FACTORas load factor.- Parameters:
strategy- the strategy.
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ByteLinkedOpenCustomHashSet
public ByteLinkedOpenCustomHashSet(Collection<? extends Byte> c, float f, ByteHash.Strategy strategy) Creates a new hash set copying a given collection.- Parameters:
c- aCollectionto be copied into the new hash set.f- the load factor.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor copying a given collection.- Parameters:
c- aCollectionto be copied into the new hash set.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set copying a given type-specific collection.- Parameters:
c- a type-specific collection to be copied into the new hash set.f- the load factor.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor copying a given type-specific collection.- Parameters:
c- a type-specific collection to be copied into the new hash set.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set using elements provided by a type-specific iterator.- Parameters:
i- a type-specific iterator whose elements will fill the set.f- the load factor.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor using elements provided by a type-specific iterator.- Parameters:
i- a type-specific iterator whose elements will fill the set.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set using elements provided by an iterator.- Parameters:
i- an iterator whose elements will fill the set.f- the load factor.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor using elements provided by an iterator.- Parameters:
i- an iterator whose elements will fill the set.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
public ByteLinkedOpenCustomHashSet(byte[] a, int offset, int length, float f, ByteHash.Strategy strategy) Creates a new hash set and fills it with the elements of a given array.- Parameters:
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.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor and fills it with the elements of a given array.- Parameters:
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.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set copying the elements of an array.- Parameters:
a- an array to be copied into the new hash set.f- the load factor.strategy- the strategy.
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ByteLinkedOpenCustomHashSet
Creates a new hash set withHash.DEFAULT_LOAD_FACTORas load factor copying the elements of an array.- Parameters:
a- an array to be copied into the new hash set.strategy- the strategy.
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Method Details
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strategy
Returns the hashing strategy.- Returns:
- the hashing strategy of this custom hash set.
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ensureCapacity
public void ensureCapacity(int capacity) Ensures that this set can hold a certain number of elements without rehashing.- Parameters:
capacity- a number of elements; there will be no rehashing unless the set size exceeds this number.
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addAll
Description copied from interface:ByteCollectionAdds all elements of the given type-specific collection to this collection.- Specified by:
addAllin interfaceByteCollection- Overrides:
addAllin classAbstractByteCollection- Parameters:
c- a type-specific collection.- Returns:
trueif this collection changed as a result of the call.- See Also:
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addAll
Description copied from class:AbstractByteCollection- Specified by:
addAllin interfaceCollection<Byte>- Specified by:
addAllin interfaceSet<Byte>- Overrides:
addAllin classAbstractByteCollection
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add
public boolean add(byte k) Description copied from class:AbstractByteCollectionEnsures that this collection contains the specified element (optional operation).- Specified by:
addin interfaceByteCollection- Overrides:
addin classAbstractByteCollection- See Also:
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remove
public boolean remove(byte k) Description copied from class:AbstractByteSetRemoves an element from this set. Delegates to the type-specificrem()method implemented by type-specific abstractCollectionsuperclass.- Specified by:
removein interfaceByteSet- Overrides:
removein classAbstractByteSet- See Also:
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contains
public boolean contains(byte k) Description copied from class:AbstractByteCollectionReturnstrueif this collection contains the specified element.- Specified by:
containsin interfaceByteCollection- Overrides:
containsin classAbstractByteCollection- See Also:
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removeFirstByte
public byte removeFirstByte()Removes the first key in iteration order.- Returns:
- the first key.
- Throws:
NoSuchElementException- is this set is empty.
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removeLastByte
public byte removeLastByte()Removes the the last key in iteration order.- Returns:
- the last key.
- Throws:
NoSuchElementException- is this set is empty.
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addAndMoveToFirst
public boolean addAndMoveToFirst(byte k) Adds a key to the set; if the key is already present, it is moved to the first position of the iteration order.- Parameters:
k- the key.- Returns:
- true if the key was not present.
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addAndMoveToLast
public boolean addAndMoveToLast(byte k) Adds a key to the set; if the key is already present, it is moved to the last position of the iteration order.- Parameters:
k- the key.- Returns:
- true if the key was not present.
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clear
public void clear()Removes all elements from this set.To increase object reuse, this method does not change the table size. If you want to reduce the table size, you must use
trim().- Specified by:
clearin interfaceCollection<Byte>- Specified by:
clearin interfaceSet<Byte>- Overrides:
clearin classAbstractCollection<Byte>
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size
public int size()- Specified by:
sizein interfaceCollection<Byte>- Specified by:
sizein interfaceSet<Byte>- Specified by:
sizein classAbstractCollection<Byte>
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isEmpty
public boolean isEmpty()- Specified by:
isEmptyin interfaceCollection<Byte>- Specified by:
isEmptyin interfaceSet<Byte>- Overrides:
isEmptyin classAbstractCollection<Byte>
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firstByte
public byte firstByte()Returns the first element of this set in iteration order.- Specified by:
firstBytein interfaceByteSortedSet- Returns:
- the first element in iteration order.
- See Also:
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lastByte
public byte lastByte()Returns the last element of this set in iteration order.- Specified by:
lastBytein interfaceByteSortedSet- Returns:
- the last element in iteration order.
- See Also:
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tailSet
Returns a view of the portion of this sorted set whose elements are greater than or equal tofromElement.- Specified by:
tailSetin interfaceByteSortedSet- See Also:
- Implementation Specification:
- This implementation just throws an
UnsupportedOperationException.
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headSet
Returns a view of the portion of this sorted set whose elements are strictly less thantoElement.- Specified by:
headSetin interfaceByteSortedSet- See Also:
- Implementation Specification:
- This implementation just throws an
UnsupportedOperationException.
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subSet
Returns a view of the portion of this sorted set whose elements range fromfromElement, inclusive, totoElement, exclusive.- Specified by:
subSetin interfaceByteSortedSet- See Also:
- Implementation Specification:
- This implementation just throws an
UnsupportedOperationException.
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comparator
- Specified by:
comparatorin interfaceByteSortedSet- Specified by:
comparatorin interfaceSortedSet<Byte>- Implementation Specification:
- This implementation just returns
null.
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iterator
Returns a type-specific list iterator on the elements in this set, starting from a given element of the set. Please see the class documentation for implementation details.- Specified by:
iteratorin interfaceByteSortedSet- Parameters:
from- an element to start from.- Returns:
- a type-specific list iterator starting at the given element.
- Throws:
IllegalArgumentException- iffromdoes not belong to the set.
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iterator
Returns a type-specific list iterator on the elements in this set, starting from the first element. Please see the class documentation for implementation details.- Specified by:
iteratorin interfaceByteBidirectionalIterable- Specified by:
iteratorin interfaceByteCollection- Specified by:
iteratorin interfaceByteIterable- Specified by:
iteratorin interfaceByteSet- Specified by:
iteratorin interfaceByteSortedSet- Specified by:
iteratorin interfaceCollection<Byte>- Specified by:
iteratorin interfaceIterable<Byte>- Specified by:
iteratorin interfaceSet<Byte>- Specified by:
iteratorin classAbstractByteSortedSet- Returns:
- a type-specific list iterator starting at the first element.
- See Also:
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spliterator
Returns a type-specific spliterator on the elements of this collection.See
Collection.spliterator()for more documentation on the requirements of the returned spliterator.There isn't a way to split efficiently while still preserving order for a linked data structure, so this implementation is just backed by the iterator. Thus, this spliterator is not well optimized for parallel streams.
Note, contrary to the specification of
SortedSet, this spliterator does not, reportSpliterator.SORTED. This is because iteration order is based on insertion order, not natural ordering.- Specified by:
spliteratorin interfaceByteCollection- Specified by:
spliteratorin interfaceByteIterable- Specified by:
spliteratorin interfaceByteSet- Specified by:
spliteratorin interfaceByteSortedSet- Specified by:
spliteratorin interfaceCollection<Byte>- Specified by:
spliteratorin interfaceIterable<Byte>- Specified by:
spliteratorin interfaceSet<Byte>- Specified by:
spliteratorin interfaceSortedSet<Byte>- Returns:
- a type-specific spliterator on the elements of this collection.
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forEach
Description copied from interface:ByteIterablePerforms the given action for each element of this type-specificIterableuntil all elements have been processed or the action throws an exception.- Specified by:
forEachin interfaceByteIterable- Parameters:
action- the action to be performed for each element.- See Also:
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trim
public boolean trim()Rehashes this set, making the table as small as possible.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.
- Returns:
- true if there was enough memory to trim the set.
- See Also:
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trim
public boolean trim(int n) Rehashes this set if the table is too large.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.
- Parameters:
n- the threshold for the trimming.- Returns:
- true if there was enough memory to trim the set.
- See Also:
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clone
Returns a deep copy of this set.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.
- Returns:
- a deep copy of this set.
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hashCode
public int hashCode()Returns a hash code for this set. This method overrides the generic method provided by the superclass. Sinceequals()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.- Specified by:
hashCodein interfaceCollection<Byte>- Specified by:
hashCodein interfaceSet<Byte>- Overrides:
hashCodein classAbstractByteSet- Returns:
- a hash code for this set.
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