public class Long2LongOpenHashMap extends AbstractLong2LongMap implements java.io.Serializable, java.lang.Cloneable, Hash
Instances of this class use a hash table to represent a map. 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 maps 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.
Hash
,
HashCommon
,
Serialized FormAbstractLong2LongMap.BasicEntry, AbstractLong2LongMap.BasicEntrySet
Hash.Strategy<K>
Long2LongMap.Entry, Long2LongMap.FastEntrySet
DEFAULT_GROWTH_FACTOR, DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR, FAST_LOAD_FACTOR, FREE, OCCUPIED, PRIMES, REMOVED, VERY_FAST_LOAD_FACTOR
Constructor and Description |
---|
Long2LongOpenHashMap()
Creates a new hash map with initial expected
Hash.DEFAULT_INITIAL_SIZE entries and
Hash.DEFAULT_LOAD_FACTOR as load factor. |
Long2LongOpenHashMap(int expected)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor. |
Long2LongOpenHashMap(int expected,
float f)
Creates a new hash map.
|
Long2LongOpenHashMap(long[] k,
long[] v)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor
using the elements of two parallel arrays. |
Long2LongOpenHashMap(long[] k,
long[] v,
float f)
Creates a new hash map using the elements of two parallel arrays.
|
Long2LongOpenHashMap(Long2LongMap m)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given type-specific one. |
Long2LongOpenHashMap(Long2LongMap m,
float f)
Creates a new hash map copying a given type-specific one.
|
Long2LongOpenHashMap(java.util.Map<? extends java.lang.Long,? extends java.lang.Long> m)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given one. |
Long2LongOpenHashMap(java.util.Map<? extends java.lang.Long,? extends java.lang.Long> m,
float f)
Creates a new hash map copying a given one.
|
Modifier and Type | Method and Description |
---|---|
long |
addTo(long k,
long incr)
Adds an increment to value currently associated with a key.
|
void |
clear()
Removes all of the mappings from this map (optional operation).
|
Long2LongOpenHashMap |
clone()
Returns a deep copy of this map.
|
long |
compute(long k,
java.util.function.BiFunction<? super java.lang.Long,? super java.lang.Long,? extends java.lang.Long> remappingFunction)
Attempts to compute a mapping for the specified key and its current mapped
value (or
null if there is no current mapping). |
long |
computeIfAbsent(long k,
java.util.function.LongUnaryOperator mappingFunction)
If the specified key is not already associated with a value, attempts to
compute its value using the given mapping function and enters it into this
map.
|
long |
computeIfAbsentNullable(long k,
java.util.function.LongFunction<? extends java.lang.Long> mappingFunction)
If the specified key is not already associated with a value, attempts to
compute its value using the given mapping function and enters it into this
map unless it is
null . |
long |
computeIfPresent(long k,
java.util.function.BiFunction<? super java.lang.Long,? super java.lang.Long,? extends java.lang.Long> remappingFunction)
If the value for the specified key is present, attempts to compute a new
mapping given the key and its current mapped value.
|
boolean |
containsKey(long k)
Returns true if this function contains a mapping for the specified key.
|
boolean |
containsValue(long v)
Returns
true if this map maps one or more keys to the specified
value. |
long |
get(long k)
Returns the value to which the given key is mapped.
|
long |
getOrDefault(long k,
long defaultValue)
Returns the value to which the specified key is mapped, or the
defaultValue if this map contains no mapping for the key. |
int |
hashCode()
Returns a hash code for this map.
|
boolean |
isEmpty() |
LongSet |
keySet()
Returns a type-specific-set view of the keys of this map.
|
Long2LongMap.FastEntrySet |
long2LongEntrySet()
Returns a type-specific set view of the mappings contained in this map.
|
long |
merge(long k,
long v,
java.util.function.BiFunction<? super java.lang.Long,? super java.lang.Long,? extends java.lang.Long> remappingFunction)
If the specified key is not already associated with a value, associates it
with the given
value . |
long |
put(long k,
long v)
Adds a pair to the map (optional operation).
|
void |
putAll(java.util.Map<? extends java.lang.Long,? extends java.lang.Long> m) |
long |
putIfAbsent(long k,
long v)
If the specified key is not already associated with a value, associates it
with the given value and returns the default return value, else returns the current value.
|
long |
remove(long k)
Removes the mapping with the given key (optional operation).
|
boolean |
remove(long k,
long v)
Removes the entry for the specified key only if it is currently mapped to the
specified value.
|
long |
replace(long k,
long v)
Replaces the entry for the specified key only if it is currently mapped to
some value.
|
boolean |
replace(long k,
long oldValue,
long v)
Replaces the entry for the specified key only if currently mapped to the
specified value.
|
int |
size()
Returns the number of key/value mappings in this map.
|
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.
|
LongCollection |
values()
Returns a type-specific-set view of the values of this map.
|
equals, toString
defaultReturnValue, defaultReturnValue
compute, computeIfAbsent, computeIfAbsentPartial, computeIfPresent, containsKey, containsValue, defaultReturnValue, defaultReturnValue, entrySet, get, getOrDefault, merge, put, putIfAbsent, remove, remove, replace, replace
applyAsLong
public Long2LongOpenHashMap(int 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 hash map.f
- the load factor.public Long2LongOpenHashMap(int expected)
Hash.DEFAULT_LOAD_FACTOR
as load factor.expected
- the expected number of elements in the hash map.public Long2LongOpenHashMap()
Hash.DEFAULT_INITIAL_SIZE
entries and
Hash.DEFAULT_LOAD_FACTOR
as load factor.public Long2LongOpenHashMap(java.util.Map<? extends java.lang.Long,? extends java.lang.Long> m, float f)
m
- a Map
to be copied into the new hash map.f
- the load factor.public Long2LongOpenHashMap(java.util.Map<? extends java.lang.Long,? extends java.lang.Long> m)
Hash.DEFAULT_LOAD_FACTOR
as load factor
copying a given one.m
- a Map
to be copied into the new hash map.public Long2LongOpenHashMap(Long2LongMap m, float f)
m
- a type-specific map to be copied into the new hash map.f
- the load factor.public Long2LongOpenHashMap(Long2LongMap m)
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.public Long2LongOpenHashMap(long[] k, long[] v, float f)
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.java.lang.IllegalArgumentException
- if k
and v
have different lengths.public Long2LongOpenHashMap(long[] k, long[] v)
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.java.lang.IllegalArgumentException
- if k
and v
have different lengths.public void putAll(java.util.Map<? extends java.lang.Long,? extends java.lang.Long> m)
AbstractLong2LongMap
putAll
in interface java.util.Map<java.lang.Long,java.lang.Long>
putAll
in class AbstractLong2LongMap
public long put(long k, long v)
Long2LongFunction
put
in interface Long2LongFunction
k
- the key.v
- the value.Function.put(Object,Object)
public long addTo(long k, long incr)
Note that this method respects the default return value semantics: when called with a key that does not currently appears in the map, the key will be associated with the default return value plus the given increment.
k
- the key.incr
- the increment.public long remove(long k)
Long2LongFunction
remove
in interface Long2LongFunction
k
- the key.Function.remove(Object)
public long get(long k)
Long2LongFunction
get
in interface Long2LongFunction
k
- the key.Function.get(Object)
public boolean containsKey(long k)
Long2LongMap
containsKey
in interface Long2LongFunction
containsKey
in interface Long2LongMap
containsKey
in class AbstractLong2LongMap
k
- the key.key
.Map.containsKey(Object)
public boolean containsValue(long v)
Long2LongMap
true
if this map maps one or more keys to the specified
value.containsValue
in interface Long2LongMap
containsValue
in class AbstractLong2LongMap
Map.containsValue(Object)
public long getOrDefault(long k, long defaultValue)
defaultValue
if this map contains no mapping for the key.getOrDefault
in interface Long2LongMap
k
- the key.defaultValue
- the default mapping of the key.defaultValue
if this map contains no mapping for the key.Map.getOrDefault(Object, Object)
public long putIfAbsent(long k, long v)
putIfAbsent
in interface Long2LongMap
k
- key with which the specified value is to be associated.v
- value to be associated with the specified key.Map.putIfAbsent(Object, Object)
public boolean remove(long k, long v)
remove
in interface Long2LongMap
k
- key with which the specified value is associated.v
- value expected to be associated with the specified key.true
if the value was removed.Map.remove(Object, Object)
public boolean replace(long k, long oldValue, long v)
replace
in interface Long2LongMap
k
- key with which the specified value is associated.oldValue
- value expected to be associated with the specified key.v
- value to be associated with the specified key.true
if the value was replaced.Map.replace(Object, Object, Object)
public long replace(long k, long v)
replace
in interface Long2LongMap
k
- key with which the specified value is associated.v
- value to be associated with the specified key.Map.replace(Object, Object)
public long computeIfAbsent(long k, java.util.function.LongUnaryOperator mappingFunction)
Note that contrarily to the default
computeIfAbsent(), it is not possible to not add a value for a given key,
since the mappingFunction
cannot return null
. If such a
behavior is needed, please use the corresponding nullable version.
computeIfAbsent
in interface Long2LongMap
k
- key with which the specified value is to be associated.mappingFunction
- the function to compute a value.Map.computeIfAbsent(Object, java.util.function.Function)
public long computeIfAbsentNullable(long k, java.util.function.LongFunction<? extends java.lang.Long> mappingFunction)
null
.
Note that this version of
computeIfAbsent() should be used only if you plan to return null
in
the mapping function.
computeIfAbsentNullable
in interface Long2LongMap
k
- key with which the specified value is to be associated.mappingFunction
- the function to compute a value.null
.Map.computeIfAbsent(Object, java.util.function.Function)
public long computeIfPresent(long k, java.util.function.BiFunction<? super java.lang.Long,? super java.lang.Long,? extends java.lang.Long> remappingFunction)
computeIfPresent
in interface Long2LongMap
k
- key with which the specified value is to be associated.remappingFunction
- the function to compute a value.Map.computeIfPresent(Object, java.util.function.BiFunction)
public long compute(long k, java.util.function.BiFunction<? super java.lang.Long,? super java.lang.Long,? extends java.lang.Long> remappingFunction)
null
if there is no current mapping).
If the function returns null
, the mapping is removed (or remains
absent if initially absent). If the function itself throws an (unchecked)
exception, the exception is rethrown, and the current mapping is left
unchanged.
compute
in interface Long2LongMap
k
- key with which the specified value is to be associated.remappingFunction
- the function to compute a value.Map.compute(Object, java.util.function.BiFunction)
public long merge(long k, long v, java.util.function.BiFunction<? super java.lang.Long,? super java.lang.Long,? extends java.lang.Long> remappingFunction)
value
. Otherwise, replaces the associated value with
the results of the given remapping function, or removes if the result is
null
.merge
in interface Long2LongMap
k
- key with which the resulting value is to be associated.v
- the value to be merged with the existing value associated with the
key or, if no existing value is associated with the key, to be
associated with the key.remappingFunction
- the function to recompute a value if present.Map.merge(Object, Object, java.util.function.BiFunction)
public void clear()
Long2LongMap
clear
in interface Long2LongMap
clear
in interface java.util.Map<java.lang.Long,java.lang.Long>
Map.clear()
public int size()
Long2LongMap
Integer.MAX_VALUE
elements, returns
Integer.MAX_VALUE
.size
in interface Long2LongMap
size
in interface java.util.Map<java.lang.Long,java.lang.Long>
Size64
public boolean isEmpty()
isEmpty
in interface java.util.Map<java.lang.Long,java.lang.Long>
isEmpty
in class AbstractLong2LongMap
public Long2LongMap.FastEntrySet long2LongEntrySet()
Long2LongMap
This method is necessary because there is no inheritance along type
parameters: it is thus impossible to strengthen Map.entrySet()
so
that it returns an ObjectSet
of
type-specific entries (the latter makes it possible to access keys and values
with type-specific methods).
long2LongEntrySet
in interface Long2LongMap
Map.entrySet()
public LongSet keySet()
AbstractLong2LongMap
The view is backed by the set returned by Map.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 Long2LongMap
keySet
in interface java.util.Map<java.lang.Long,java.lang.Long>
keySet
in class AbstractLong2LongMap
Map.keySet()
public LongCollection values()
AbstractLong2LongMap
The view is backed by the set returned by Map.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 Long2LongMap
values
in interface java.util.Map<java.lang.Long,java.lang.Long>
values
in class AbstractLong2LongMap
Map.values()
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 Long2LongOpenHashMap 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.
clone
in class java.lang.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 java.util.Map<java.lang.Long,java.lang.Long>
hashCode
in class AbstractLong2LongMap