public class Double2ReferenceOpenCustomHashMap<V> extends AbstractDouble2ReferenceMap<V> implements Serializable, Cloneable, Hash
Instances of this class use a hash table to represent a map. 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 FormAbstractDouble2ReferenceMap.BasicEntry<V>
Hash.Strategy<K>
Double2ReferenceMap.Entry<V>, Double2ReferenceMap.FastEntrySet<V>
DEFAULT_GROWTH_FACTOR, DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR, FAST_LOAD_FACTOR, FREE, OCCUPIED, PRIMES, REMOVED, VERY_FAST_LOAD_FACTOR
Constructor and Description |
---|
Double2ReferenceOpenCustomHashMap(double[] k,
V[] v,
DoubleHash.Strategy strategy)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor using the elements of two parallel arrays. |
Double2ReferenceOpenCustomHashMap(double[] k,
V[] v,
float f,
DoubleHash.Strategy strategy)
Creates a new hash map using the elements of two parallel arrays.
|
Double2ReferenceOpenCustomHashMap(Double2ReferenceMap<V> m,
DoubleHash.Strategy strategy)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor copying a given type-specific one. |
Double2ReferenceOpenCustomHashMap(Double2ReferenceMap<V> m,
float f,
DoubleHash.Strategy strategy)
Creates a new hash map copying a given type-specific one.
|
Double2ReferenceOpenCustomHashMap(DoubleHash.Strategy strategy)
Creates a new hash map with initial expected
Hash.DEFAULT_INITIAL_SIZE entries
and Hash.DEFAULT_LOAD_FACTOR as load factor. |
Double2ReferenceOpenCustomHashMap(int expected,
DoubleHash.Strategy strategy)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor. |
Double2ReferenceOpenCustomHashMap(int expected,
float f,
DoubleHash.Strategy strategy)
Creates a new hash map.
|
Double2ReferenceOpenCustomHashMap(Map<? extends Double,? extends V> m,
DoubleHash.Strategy strategy)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor copying a given one. |
Double2ReferenceOpenCustomHashMap(Map<? extends Double,? extends V> m,
float f,
DoubleHash.Strategy strategy)
Creates a new hash map copying a given one.
|
Modifier and Type | Method and Description |
---|---|
void |
clear()
Removes all associations from this function (optional operation).
|
Double2ReferenceOpenCustomHashMap<V> |
clone()
Returns a deep copy of this map.
|
boolean |
containsKey(double k)
Checks whether the given value is contained in
AbstractDouble2ReferenceMap.keySet() . |
boolean |
containsValue(Object v)
Checks whether the given value is contained in
AbstractDouble2ReferenceMap.values() . |
Double2ReferenceMap.FastEntrySet<V> |
double2ReferenceEntrySet()
Returns a type-specific set view of the mappings contained in this map.
|
V |
get(double k)
Returns the value to which the given key is mapped.
|
V |
get(Double ok) |
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 map.
|
boolean |
isEmpty() |
DoubleSet |
keySet()
Returns a type-specific-set view of the keys of this map.
|
V |
put(double k,
V v)
Adds a pair to the map.
|
V |
put(Double ok,
V ov)
Delegates to the corresponding type-specific method, taking care of returning
null on a missing key. |
boolean |
rehash()
Deprecated.
A no-op.
|
V |
remove(double k)
Removes the mapping with the given key.
|
V |
remove(Object ok)
Delegates to the corresponding type-specific method, taking care of returning
null on a missing key. |
int |
size()
Returns the intended number of keys in this function, or -1 if no such number exists.
|
DoubleHash.Strategy |
strategy()
Returns the hashing strategy.
|
boolean |
trim()
Rehashes the map, making the table as small as possible.
|
boolean |
trim(int n)
Rehashes this map if the table is too large.
|
ReferenceCollection<V> |
values()
Returns a type-specific-set view of the values of this map.
|
entrySet, equals, putAll, toString
containsKey, defaultReturnValue, defaultReturnValue, get
defaultReturnValue, defaultReturnValue
containsKey, get
containsKey, get
public Double2ReferenceOpenCustomHashMap(int expected, float f, DoubleHash.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 Double2ReferenceOpenCustomHashMap(int expected, DoubleHash.Strategy strategy)
Hash.DEFAULT_LOAD_FACTOR
as load factor.expected
- the expected number of elements in the hash map.strategy
- the strategy.public Double2ReferenceOpenCustomHashMap(DoubleHash.Strategy strategy)
Hash.DEFAULT_INITIAL_SIZE
entries
and Hash.DEFAULT_LOAD_FACTOR
as load factor.strategy
- the strategy.public Double2ReferenceOpenCustomHashMap(Map<? extends Double,? extends V> m, float f, DoubleHash.Strategy strategy)
m
- a Map
to be copied into the new hash map.f
- the load factor.strategy
- the strategy.public Double2ReferenceOpenCustomHashMap(Map<? extends Double,? extends V> m, DoubleHash.Strategy strategy)
Hash.DEFAULT_LOAD_FACTOR
as load factor copying a given one.m
- a Map
to be copied into the new hash map.strategy
- the strategy.public Double2ReferenceOpenCustomHashMap(Double2ReferenceMap<V> m, float f, DoubleHash.Strategy strategy)
m
- a type-specific map to be copied into the new hash map.f
- the load factor.strategy
- the strategy.public Double2ReferenceOpenCustomHashMap(Double2ReferenceMap<V> m, DoubleHash.Strategy strategy)
Hash.DEFAULT_LOAD_FACTOR
as load factor copying a given type-specific one.m
- a type-specific map to be copied into the new hash map.strategy
- the strategy.public Double2ReferenceOpenCustomHashMap(double[] k, V[] v, float f, DoubleHash.Strategy strategy)
k
- the array of keys of the new hash map.v
- the array of corresponding values in the new hash map.f
- the load factor.strategy
- the strategy.IllegalArgumentException
- if k
and v
have different lengths.public Double2ReferenceOpenCustomHashMap(double[] k, V[] v, DoubleHash.Strategy strategy)
Hash.DEFAULT_LOAD_FACTOR
as load factor using the elements of two parallel arrays.k
- the array of keys of the new hash map.v
- the array of corresponding values in the new hash map.strategy
- the strategy.IllegalArgumentException
- if k
and v
have different lengths.public DoubleHash.Strategy strategy()
public V put(double k, V v)
Double2ReferenceFunction
put
in interface Double2ReferenceFunction<V>
put
in class AbstractDouble2ReferenceFunction<V>
k
- the key.v
- the value.Function.put(Object,Object)
public V put(Double ok, V ov)
AbstractDouble2ReferenceFunction
null
on a missing key.
This method must check whether the provided key is in the map using containsKey()
. Thus,
it probes the map twice. Implementors of subclasses should override it with a more efficient method.
public V remove(double k)
Double2ReferenceFunction
remove
in interface Double2ReferenceFunction<V>
remove
in class AbstractDouble2ReferenceFunction<V>
Function.remove(Object)
public V remove(Object ok)
AbstractDouble2ReferenceFunction
null
on a missing key.
This method must check whether the provided key is in the map using containsKey()
. Thus,
it probes the map twice. Implementors of subclasses should override it with a more efficient method.
public V get(double k)
Double2ReferenceFunction
get
in interface Double2ReferenceFunction<V>
k
- the key.Function.get(Object)
public boolean containsKey(double k)
AbstractDouble2ReferenceMap
AbstractDouble2ReferenceMap.keySet()
.containsKey
in interface Double2ReferenceFunction<V>
containsKey
in class AbstractDouble2ReferenceMap<V>
Function.containsKey(Object)
public boolean containsValue(Object v)
AbstractDouble2ReferenceMap
AbstractDouble2ReferenceMap.values()
.containsValue
in interface Map<Double,V>
containsValue
in class AbstractDouble2ReferenceMap<V>
public void clear()
Function
public int size()
Function
Most function implementations will have some knowledge of the intended number of keys in their domain. In some cases, however, this might not be possible.
public boolean isEmpty()
@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 Double2ReferenceMap.FastEntrySet<V> double2ReferenceEntrySet()
Double2ReferenceMap
This method is necessary because there is no inheritance along
type parameters: it is thus impossible to strengthen Double2ReferenceMap.entrySet()
so that it returns an ObjectSet
of objects of type Map.Entry
(the latter makes it possible to
access keys and values with type-specific methods).
double2ReferenceEntrySet
in interface Double2ReferenceMap<V>
Double2ReferenceMap.entrySet()
public DoubleSet keySet()
AbstractDouble2ReferenceMap
The view is backed by the set returned by AbstractDouble2ReferenceMap.entrySet()
. Note that
no attempt is made at caching the result of this method, as this would
require adding some attributes that lightweight implementations would
not need. Subclasses may easily override this policy by calling
this method and caching the result, but implementors are encouraged to
write more efficient ad-hoc implementations.
keySet
in interface Double2ReferenceMap<V>
keySet
in interface Map<Double,V>
keySet
in class AbstractDouble2ReferenceMap<V>
Map.keySet()
public ReferenceCollection<V> values()
AbstractDouble2ReferenceMap
The view is backed by the set returned by AbstractDouble2ReferenceMap.entrySet()
. Note that
no attempt is made at caching the result of this method, as this would
require adding some attributes that lightweight implementations would
not need. Subclasses may easily override this policy by calling
this method and caching the result, but implementors are encouraged to
write more efficient ad-hoc implementations.
values
in interface Double2ReferenceMap<V>
values
in interface Map<Double,V>
values
in class AbstractDouble2ReferenceMap<V>
Map.values()
@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 map in a table of size
N.
size()
)
This method is useful when reusing maps. Clearing a map leaves the table size untouched. If you are reusing a map 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 maps.
n
- the threshold for the trimming.trim()
public Double2ReferenceOpenCustomHashMap<V> clone()
This method performs a deep copy of this hash map; the data stored in the map, 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.