|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectjava.util.AbstractCollection<Short>
it.unimi.dsi.fastutil.shorts.AbstractShortCollection
it.unimi.dsi.fastutil.shorts.AbstractShortSet
it.unimi.dsi.fastutil.shorts.ShortOpenCustomHashSet
public class ShortOpenCustomHashSet
A type-specific hash set with a fast, small-footprint implementation whose hashing strategy is specified at creation time.
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.
Warning: The implementation of this class has significantly
changed in fastutil
6.1.0. Please read the
comments about this issue in the section “Faster Hash Tables” of the overview.
Hash
,
HashCommon
,
Serialized FormNested Class Summary |
---|
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.Hash |
---|
Hash.Strategy<K> |
Field Summary | |
---|---|
protected float |
f
The acceptable load factor. |
protected short[] |
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 |
n
The current table size. |
static long |
serialVersionUID
|
protected int |
size
Number of entries in the set. |
protected ShortHash.Strategy |
strategy
The hash strategy of this custom set. |
protected boolean[] |
used
The array telling whether a position is used. |
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 | |
---|---|
ShortOpenCustomHashSet(Collection<? extends Short> c,
float f,
ShortHash.Strategy strategy)
Creates a new hash set copying a given collection. |
|
ShortOpenCustomHashSet(Collection<? extends Short> c,
ShortHash.Strategy strategy)
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given collection. |
|
ShortOpenCustomHashSet(int expected,
float f,
ShortHash.Strategy strategy)
Creates a new hash set. |
|
ShortOpenCustomHashSet(int expected,
ShortHash.Strategy strategy)
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor. |
|
ShortOpenCustomHashSet(Iterator<?> i,
float f,
ShortHash.Strategy strategy)
Creates a new hash set using elements provided by an iterator. |
|
ShortOpenCustomHashSet(Iterator<?> i,
ShortHash.Strategy strategy)
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by an iterator. |
|
ShortOpenCustomHashSet(short[] a,
float f,
ShortHash.Strategy strategy)
Creates a new hash set copying the elements of an array. |
|
ShortOpenCustomHashSet(short[] a,
int offset,
int length,
float f,
ShortHash.Strategy strategy)
Creates a new hash set and fills it with the elements of a given array. |
|
ShortOpenCustomHashSet(short[] a,
int offset,
int length,
ShortHash.Strategy strategy)
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor and fills it with the elements of a given array. |
|
ShortOpenCustomHashSet(short[] a,
ShortHash.Strategy strategy)
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor
copying the elements of an array. |
|
ShortOpenCustomHashSet(ShortCollection c,
float f,
ShortHash.Strategy strategy)
Creates a new hash set copying a given type-specific collection. |
|
ShortOpenCustomHashSet(ShortCollection c,
ShortHash.Strategy strategy)
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given type-specific collection. |
|
ShortOpenCustomHashSet(ShortHash.Strategy strategy)
Creates a new hash set with initial expected Hash.DEFAULT_INITIAL_SIZE elements
and Hash.DEFAULT_LOAD_FACTOR as load factor. |
|
ShortOpenCustomHashSet(ShortIterator i,
float f,
ShortHash.Strategy strategy)
Creates a new hash set using elements provided by a type-specific iterator. |
|
ShortOpenCustomHashSet(ShortIterator i,
ShortHash.Strategy strategy)
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by a type-specific iterator. |
Method Summary | |
---|---|
boolean |
add(short k)
|
void |
clear()
|
ShortOpenCustomHashSet |
clone()
Returns a deep copy of this set. |
boolean |
contains(short k)
|
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. |
boolean |
isEmpty()
|
ShortIterator |
iterator()
Returns a type-specific iterator on the elements of this collection. |
boolean |
rehash()
Deprecated. A no-op. |
protected void |
rehash(int newN)
Resizes the set. |
boolean |
remove(short k)
Removes an element from this set. |
protected int |
shiftKeys(int pos)
Shifts left entries with the specified hash code, starting at the specified position, and empties the resulting free entry. |
int |
size()
|
ShortHash.Strategy |
strategy()
Returns the hashing strategy. |
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. |
Methods inherited from class it.unimi.dsi.fastutil.shorts.AbstractShortSet |
---|
equals, rem, remove |
Methods inherited from class it.unimi.dsi.fastutil.shorts.AbstractShortCollection |
---|
add, addAll, addAll, contains, containsAll, containsAll, rem, removeAll, removeAll, retainAll, retainAll, shortIterator, toArray, toArray, toArray, toShortArray, toShortArray, toString |
Methods inherited from class java.lang.Object |
---|
finalize, getClass, notify, notifyAll, wait, wait, wait |
Methods inherited from interface it.unimi.dsi.fastutil.shorts.ShortCollection |
---|
addAll, containsAll, removeAll, retainAll, shortIterator, toArray, toArray, toShortArray, toShortArray |
Methods inherited from interface java.util.Set |
---|
add, addAll, contains, containsAll, removeAll, retainAll, toArray, toArray |
Field Detail |
---|
public static final long serialVersionUID
protected transient short[] key
protected transient boolean[] used
protected final float f
protected transient int n
protected transient int maxFill
f
.
protected transient int mask
protected int size
protected ShortHash.Strategy strategy
Constructor Detail |
---|
public ShortOpenCustomHashSet(int expected, float f, ShortHash.Strategy strategy)
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.strategy
- the strategy.public ShortOpenCustomHashSet(int expected, ShortHash.Strategy strategy)
Hash.DEFAULT_LOAD_FACTOR
as load factor.
expected
- the expected number of elements in the hash set.strategy
- the strategy.public ShortOpenCustomHashSet(ShortHash.Strategy strategy)
Hash.DEFAULT_INITIAL_SIZE
elements
and Hash.DEFAULT_LOAD_FACTOR
as load factor.
strategy
- the strategy.public ShortOpenCustomHashSet(Collection<? extends Short> c, float f, ShortHash.Strategy strategy)
c
- a Collection
to be copied into the new hash set.f
- the load factor.strategy
- the strategy.public ShortOpenCustomHashSet(Collection<? extends Short> c, ShortHash.Strategy strategy)
Hash.DEFAULT_LOAD_FACTOR
as load factor
copying a given collection.
c
- a Collection
to be copied into the new hash set.strategy
- the strategy.public ShortOpenCustomHashSet(ShortCollection c, float f, ShortHash.Strategy strategy)
c
- a type-specific collection to be copied into the new hash set.f
- the load factor.strategy
- the strategy.public ShortOpenCustomHashSet(ShortCollection c, ShortHash.Strategy strategy)
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.strategy
- the strategy.public ShortOpenCustomHashSet(ShortIterator i, float f, ShortHash.Strategy strategy)
i
- a type-specific iterator whose elements will fill the set.f
- the load factor.strategy
- the strategy.public ShortOpenCustomHashSet(ShortIterator i, ShortHash.Strategy strategy)
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.strategy
- the strategy.public ShortOpenCustomHashSet(Iterator<?> i, float f, ShortHash.Strategy strategy)
i
- an iterator whose elements will fill the set.f
- the load factor.strategy
- the strategy.public ShortOpenCustomHashSet(Iterator<?> i, ShortHash.Strategy strategy)
Hash.DEFAULT_LOAD_FACTOR
as load factor using elements provided by an iterator.
i
- an iterator whose elements will fill the set.strategy
- the strategy.public ShortOpenCustomHashSet(short[] a, int offset, int length, float f, ShortHash.Strategy strategy)
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.public ShortOpenCustomHashSet(short[] a, int offset, int length, ShortHash.Strategy strategy)
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.strategy
- the strategy.public ShortOpenCustomHashSet(short[] a, float f, ShortHash.Strategy strategy)
a
- an array to be copied into the new hash set.f
- the load factor.strategy
- the strategy.public ShortOpenCustomHashSet(short[] a, ShortHash.Strategy strategy)
Hash.DEFAULT_LOAD_FACTOR
as load factor
copying the elements of an array.
a
- an array to be copied into the new hash set.strategy
- the strategy.Method Detail |
---|
public ShortHash.Strategy strategy()
public boolean add(short k)
add
in interface ShortCollection
add
in class AbstractShortCollection
Collection.add(Object)
protected final int shiftKeys(int pos)
pos
- a starting position.
public boolean remove(short k)
ShortSet
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 ShortSet
remove
in class AbstractShortSet
Collection.remove(Object)
public boolean contains(short k)
contains
in interface ShortCollection
contains
in class AbstractShortCollection
Collection.contains(Object)
public void clear()
clear
in interface Collection<Short>
clear
in interface Set<Short>
clear
in class AbstractCollection<Short>
public int size()
size
in interface Collection<Short>
size
in interface Set<Short>
size
in class AbstractCollection<Short>
public boolean isEmpty()
isEmpty
in interface Collection<Short>
isEmpty
in interface Set<Short>
isEmpty
in class AbstractShortCollection
@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 ShortIterator iterator()
ShortCollection
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 ShortCollection
iterator
in interface ShortIterable
iterator
in interface ShortSet
iterator
in interface Iterable<Short>
iterator
in interface Collection<Short>
iterator
in interface Set<Short>
iterator
in class AbstractShortSet
@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()
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 ShortOpenCustomHashSet 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.
clone
in class Object
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<Short>
hashCode
in interface Set<Short>
hashCode
in class AbstractShortSet
|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |