Class Double2CharLinkedOpenHashMap
- All Implemented Interfaces:
Double2CharFunction
,Double2CharMap
,Double2CharSortedMap
,Function<Double,
,Character> Hash
,Serializable
,Cloneable
,DoubleToIntFunction
,Function<Double,
,Character> Map<Double,
,Character> SequencedMap<Double,
,Character> SortedMap<Double,
Character>
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.
Entries returned by the type-specific Double2CharMap.entrySet()
method implement the suitable
type-specific Pair
interface; only values are mutable.
Iterators generated by this map will enumerate pairs in the same order in which they have been added to the map (addition of pairs whose key is already present in the map 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 map, so to allow easy access of the iteration
order: for instance, you can get the first key in iteration order with firstKey()
without
having to create an iterator; however, this class partially violates the
SortedMap
contract because all submap methods throw an exception and
comparator()
returns always null
.
Additional methods, such as getAndMoveToFirst()
, make it easy to use instances of this
class as a cache (e.g., with LRU policy).
The iterators provided by the views of this class using are type-specific
list iterators, and can be started at any element which
is a key of the map, or a NoSuchElementException
exception will be thrown. If,
however, the provided element is not the first or last key in the map, the first access to the
list index will require linear time, as in the worst case the entire key set must be scanned in
iteration order to retrieve the positional index of the starting key. 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 class it.unimi.dsi.fastutil.doubles.AbstractDouble2CharMap
AbstractDouble2CharMap.BasicEntry, AbstractDouble2CharMap.BasicEntrySet
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.doubles.Double2CharMap
Double2CharMap.Entry, Double2CharMap.FastEntrySet
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.doubles.Double2CharSortedMap
Double2CharSortedMap.FastSortedEntrySet
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.Hash
Hash.Strategy<K>
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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
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Constructor Summary
ConstructorDescriptionCreates a new hash map with initial expectedHash.DEFAULT_INITIAL_SIZE
entries andHash.DEFAULT_LOAD_FACTOR
as load factor.Double2CharLinkedOpenHashMap
(double[] k, char[] v) Creates a new hash map withHash.DEFAULT_LOAD_FACTOR
as load factor using the elements of two parallel arrays.Double2CharLinkedOpenHashMap
(double[] k, char[] v, float f) Creates a new hash map using the elements of two parallel arrays.Double2CharLinkedOpenHashMap
(int expected) Creates a new hash map withHash.DEFAULT_LOAD_FACTOR
as load factor.Double2CharLinkedOpenHashMap
(int expected, float f) Creates a new hash map.Creates a new hash map withHash.DEFAULT_LOAD_FACTOR
as load factor copying a given type-specific one.Double2CharLinkedOpenHashMap
(Double2CharMap m, float f) Creates a new hash map copying a given type-specific one.Double2CharLinkedOpenHashMap
(Map<? extends Double, ? extends Character> m) Creates a new hash map withHash.DEFAULT_LOAD_FACTOR
as load factor copying a given one.Double2CharLinkedOpenHashMap
(Map<? extends Double, ? extends Character> m, float f) Creates a new hash map copying a given one. -
Method Summary
Modifier and TypeMethodDescriptionchar
addTo
(double k, char incr) Adds an increment to value currently associated with a key.void
clear()
Removes all of the mappings from this map (optional operation).clone()
Returns a deep copy of this map.Returns the comparator associated with this sorted set, or null if it uses its keys' natural ordering.char
compute
(double k, BiFunction<? super Double, ? super Character, ? extends Character> remappingFunction) Attempts to compute a mapping for the specified key and its current mapped value (ornull
if there is no current mapping).char
computeIfAbsent
(double key, Double2CharFunction 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 the key is not present in the given mapping function.char
computeIfAbsent
(double k, DoubleToIntFunction 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.char
computeIfAbsentNullable
(double k, DoubleFunction<? extends Character> 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 isnull
.char
computeIfPresent
(double k, BiFunction<? super Double, ? super Character, ? extends Character> 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
(double k) Returns true if this function contains a mapping for the specified key.boolean
containsValue
(char v) Returnstrue
if this map maps one or more keys to the specified value.Returns a type-specific sorted-set view of the mappings contained in this map.void
ensureCapacity
(int capacity) Ensures that this map can hold a certain number of keys without rehashing.double
Returns the first key of this map in iteration order.char
get
(double k) Returns the value to which the given key is mapped.char
getAndMoveToFirst
(double k) Returns the value to which the given key is mapped; if the key is present, it is moved to the first position of the iteration order.char
getAndMoveToLast
(double k) Returns the value to which the given key is mapped; if the key is present, it is moved to the last position of the iteration order.char
getOrDefault
(double k, char defaultValue) Returns the value to which the specified key is mapped, or thedefaultValue
if this map contains no mapping for the key.int
hashCode()
Returns a hash code for this map.headMap
(double to) Returns a view of the portion of this sorted map whose keys are strictly less thantoKey
.boolean
isEmpty()
keySet()
Returns a type-specific-set view of the keys of this map.double
Returns the last key of this map in iteration order.char
merge
(double k, char v, BiFunction<? super Character, ? super Character, ? extends Character> remappingFunction) If the specified key is not already associated with a value, associates it with the givenvalue
.char
put
(double k, char v) Adds a pair to the map (optional operation).void
char
putAndMoveToFirst
(double k, char v) Adds a pair to the map; if the key is already present, it is moved to the first position of the iteration order.char
putAndMoveToLast
(double k, char v) Adds a pair to the map; if the key is already present, it is moved to the last position of the iteration order.char
putIfAbsent
(double k, char 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.char
remove
(double k) Removes the mapping with the given key (optional operation).boolean
remove
(double k, char v) Removes the entry for the specified key only if it is currently mapped to the specified value.char
Removes the mapping associated with the first key in iteration order.char
Removes the mapping associated with the last key in iteration order.char
replace
(double k, char v) Replaces the entry for the specified key only if it is currently mapped to some value.boolean
replace
(double k, char oldValue, char 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.subMap
(double from, double to) Returns a view of the portion of this sorted map whose keys range fromfromKey
, inclusive, totoKey
, exclusive.tailMap
(double from) Returns a view of the portion of this sorted map whose keys are greater than or equal tofromKey
.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.values()
Returns a type-specific-set view of the values of this map.Methods inherited from class it.unimi.dsi.fastutil.doubles.AbstractDouble2CharMap
equals, toString
Methods inherited from class it.unimi.dsi.fastutil.doubles.AbstractDouble2CharFunction
defaultReturnValue, defaultReturnValue
Methods inherited from interface it.unimi.dsi.fastutil.doubles.Double2CharFunction
andThen, andThenByte, andThenChar, andThenDouble, andThenFloat, andThenInt, andThenLong, andThenObject, andThenReference, andThenShort, applyAsInt, compose, composeByte, composeChar, composeDouble, composeFloat, composeInt, composeLong, composeObject, composeReference, composeShort
Methods inherited from interface it.unimi.dsi.fastutil.doubles.Double2CharMap
compute, computeIfAbsent, computeIfAbsentPartial, computeIfPresent, containsKey, containsValue, defaultReturnValue, defaultReturnValue, forEach, get, getOrDefault, merge, mergeChar, mergeChar, put, putIfAbsent, remove, remove, replace, replace
Methods inherited from interface it.unimi.dsi.fastutil.doubles.Double2CharSortedMap
entrySet, firstKey, headMap, lastKey, subMap, tailMap
Methods inherited from interface java.util.Map
containsKey, equals, get, getOrDefault, put, remove, replaceAll
Methods inherited from interface java.util.SequencedMap
firstEntry, lastEntry, pollFirstEntry, pollLastEntry, sequencedEntrySet, sequencedKeySet, sequencedValues
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Constructor Details
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Double2CharLinkedOpenHashMap
public Double2CharLinkedOpenHashMap(int expected, float f) Creates a new hash map.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 map.f
- the load factor.
-
Double2CharLinkedOpenHashMap
public Double2CharLinkedOpenHashMap(int expected) Creates a new hash map withHash.DEFAULT_LOAD_FACTOR
as load factor.- Parameters:
expected
- the expected number of elements in the hash map.
-
Double2CharLinkedOpenHashMap
public Double2CharLinkedOpenHashMap()Creates a new hash map with initial expectedHash.DEFAULT_INITIAL_SIZE
entries andHash.DEFAULT_LOAD_FACTOR
as load factor. -
Double2CharLinkedOpenHashMap
Creates a new hash map copying a given one.- Parameters:
m
- aMap
to be copied into the new hash map.f
- the load factor.
-
Double2CharLinkedOpenHashMap
Creates a new hash map withHash.DEFAULT_LOAD_FACTOR
as load factor copying a given one.- Parameters:
m
- aMap
to be copied into the new hash map.
-
Double2CharLinkedOpenHashMap
Creates a new hash map copying a given type-specific one.- Parameters:
m
- a type-specific map to be copied into the new hash map.f
- the load factor.
-
Double2CharLinkedOpenHashMap
Creates a new hash map withHash.DEFAULT_LOAD_FACTOR
as load factor copying a given type-specific one.- Parameters:
m
- a type-specific map to be copied into the new hash map.
-
Double2CharLinkedOpenHashMap
public Double2CharLinkedOpenHashMap(double[] k, char[] v, float f) Creates a new hash map using the elements of two parallel arrays.- Parameters:
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.- Throws:
IllegalArgumentException
- ifk
andv
have different lengths.
-
Double2CharLinkedOpenHashMap
public Double2CharLinkedOpenHashMap(double[] k, char[] v) Creates a new hash map withHash.DEFAULT_LOAD_FACTOR
as load factor using the elements of two parallel arrays.- Parameters:
k
- the array of keys of the new hash map.v
- the array of corresponding values in the new hash map.- Throws:
IllegalArgumentException
- ifk
andv
have different lengths.
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Method Details
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ensureCapacity
public void ensureCapacity(int capacity) Ensures that this map can hold a certain number of keys without rehashing.- Parameters:
capacity
- a number of keys; there will be no rehashing unless the map size exceeds this number.
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putAll
Description copied from class:AbstractDouble2CharMap
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put
public char put(double k, char v) Description copied from interface:Double2CharFunction
Adds a pair to the map (optional operation).- Specified by:
put
in interfaceDouble2CharFunction
- Parameters:
k
- the key.v
- the value.- Returns:
- the old value, or the default return value if no value was present for the given key.
- See Also:
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addTo
public char addTo(double k, char incr) Adds an increment to value currently associated with a key.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.
- Parameters:
k
- the key.incr
- the increment.- Returns:
- the old value, or the default return value if no value was present for the given key.
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remove
public char remove(double k) Description copied from interface:Double2CharFunction
Removes the mapping with the given key (optional operation).- Specified by:
remove
in interfaceDouble2CharFunction
- Parameters:
k
- the key.- Returns:
- the old value, or the default return value if no value was present for the given key.
- See Also:
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removeFirstChar
public char removeFirstChar()Removes the mapping associated with the first key in iteration order.- Returns:
- the value previously associated with the first key in iteration order.
- Throws:
NoSuchElementException
- is this map is empty.
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removeLastChar
public char removeLastChar()Removes the mapping associated with the last key in iteration order.- Returns:
- the value previously associated with the last key in iteration order.
- Throws:
NoSuchElementException
- is this map is empty.
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getAndMoveToFirst
public char getAndMoveToFirst(double k) Returns the value to which the given key is mapped; if the key is present, it is moved to the first position of the iteration order.- Parameters:
k
- the key.- Returns:
- the corresponding value, or the default return value if no value was present for the given key.
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getAndMoveToLast
public char getAndMoveToLast(double k) Returns the value to which the given key is mapped; if the key is present, it is moved to the last position of the iteration order.- Parameters:
k
- the key.- Returns:
- the corresponding value, or the default return value if no value was present for the given key.
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putAndMoveToFirst
public char putAndMoveToFirst(double k, char v) Adds a pair to the map; if the key is already present, it is moved to the first position of the iteration order.- Parameters:
k
- the key.v
- the value.- Returns:
- the old value, or the default return value if no value was present for the given key.
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putAndMoveToLast
public char putAndMoveToLast(double k, char v) Adds a pair to the map; if the key is already present, it is moved to the last position of the iteration order.- Parameters:
k
- the key.v
- the value.- Returns:
- the old value, or the default return value if no value was present for the given key.
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get
public char get(double k) Description copied from interface:Double2CharFunction
Returns the value to which the given key is mapped.- Specified by:
get
in interfaceDouble2CharFunction
- Parameters:
k
- the key.- Returns:
- the corresponding value, or the default return value if no value was present for the given key.
- See Also:
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containsKey
public boolean containsKey(double k) Description copied from class:AbstractDouble2CharMap
Returns true if this function contains a mapping for the specified key.- Specified by:
containsKey
in interfaceDouble2CharFunction
- Specified by:
containsKey
in interfaceDouble2CharMap
- Overrides:
containsKey
in classAbstractDouble2CharMap
- Parameters:
k
- the key.- Returns:
- true if this function associates a value to
key
. - See Also:
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containsValue
public boolean containsValue(char v) Description copied from class:AbstractDouble2CharMap
Returnstrue
if this map maps one or more keys to the specified value.- Specified by:
containsValue
in interfaceDouble2CharMap
- Overrides:
containsValue
in classAbstractDouble2CharMap
- See Also:
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getOrDefault
public char getOrDefault(double k, char defaultValue) Returns the value to which the specified key is mapped, or thedefaultValue
if this map contains no mapping for the key.- Specified by:
getOrDefault
in interfaceDouble2CharFunction
- Specified by:
getOrDefault
in interfaceDouble2CharMap
- Parameters:
k
- the key.defaultValue
- the default mapping of the key.- Returns:
- the value to which the specified key is mapped, or the
defaultValue
if this map contains no mapping for the key. - See Also:
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putIfAbsent
public char putIfAbsent(double k, char 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.- Specified by:
putIfAbsent
in interfaceDouble2CharMap
- Parameters:
k
- key with which the specified value is to be associated.v
- value to be associated with the specified key.- Returns:
- the previous value associated with the specified key, or the default return value if there was no mapping for the key.
- See Also:
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remove
public boolean remove(double k, char v) Removes the entry for the specified key only if it is currently mapped to the specified value.- Specified by:
remove
in interfaceDouble2CharMap
- Parameters:
k
- key with which the specified value is associated.v
- value expected to be associated with the specified key.- Returns:
true
if the value was removed.- See Also:
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replace
public boolean replace(double k, char oldValue, char v) Replaces the entry for the specified key only if currently mapped to the specified value.- Specified by:
replace
in interfaceDouble2CharMap
- Parameters:
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.- Returns:
true
if the value was replaced.- See Also:
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replace
public char replace(double k, char v) Replaces the entry for the specified key only if it is currently mapped to some value.- Specified by:
replace
in interfaceDouble2CharMap
- Parameters:
k
- key with which the specified value is associated.v
- value to be associated with the specified key.- Returns:
- the previous value associated with the specified key, or the default return value if there was no mapping for the key.
- See Also:
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computeIfAbsent
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.Note that contrarily to the default computeIfAbsent(), it is not possible to not add a value for a given key, since the
mappingFunction
cannot returnnull
. If such a behavior is needed, please use the corresponding nullable version.- Specified by:
computeIfAbsent
in interfaceDouble2CharMap
- Parameters:
k
- key with which the specified value is to be associated.mappingFunction
- the function to compute a value.- Returns:
- the current (existing or computed) value associated with the specified key.
- See Also:
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computeIfAbsent
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 the key is not present in the given mapping function.This version of computeIfAbsent() uses a type-specific version of
fastutil
'sFunction
. SinceFunction
has acontainsKey()
method, it is possible to avoid adding a key by havingcontainsKey()
returnfalse
for that key.- Specified by:
computeIfAbsent
in interfaceDouble2CharMap
- Parameters:
key
- key with which the specified value is to be associated.mappingFunction
- the function to compute a value.- Returns:
- the current (existing or computed) value associated with the specified key.
- See Also:
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computeIfAbsentNullable
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 isnull
.Note that this version of computeIfAbsent() should be used only if you plan to return
null
in the mapping function.- Specified by:
computeIfAbsentNullable
in interfaceDouble2CharMap
- Parameters:
k
- key with which the specified value is to be associated.mappingFunction
- the function to compute a value.- Returns:
- the current (existing or computed) value associated with the specified key, or the
default return value if the computed value is
null
. - See Also:
-
computeIfPresent
public char computeIfPresent(double k, BiFunction<? super Double, ? super Character, ? extends Character> remappingFunction) If the value for the specified key is present, attempts to compute a new mapping given the key and its current mapped value.- Specified by:
computeIfPresent
in interfaceDouble2CharMap
- Parameters:
k
- key with which the specified value is to be associated.remappingFunction
- the function to compute a value.- Returns:
- the new value associated with the specified key, or the default return value if none.
- See Also:
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compute
public char compute(double k, BiFunction<? super Double, ? super Character, ? extends Character> remappingFunction) Attempts to compute a mapping for the specified key and its current mapped value (ornull
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.- Specified by:
compute
in interfaceDouble2CharMap
- Parameters:
k
- key with which the specified value is to be associated.remappingFunction
- the function to compute a value.- Returns:
- the new value associated with the specified key, or the default return value if none.
- See Also:
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merge
public char merge(double k, char v, BiFunction<? super Character, ? super Character, ? extends Character> remappingFunction) If the specified key is not already associated with a value, associates it with the givenvalue
. Otherwise, replaces the associated value with the results of the given remapping function, or removes if the result isnull
.- Specified by:
merge
in interfaceDouble2CharMap
- Parameters:
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.- Returns:
- the new value associated with the specified key, or the default return value if no value is associated with the key.
- See Also:
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clear
public void clear()Description copied from interface:Double2CharMap
Removes all of the mappings from this map (optional operation). The map will be empty after this call returns. -
size
public int size()Description copied from interface:Double2CharMap
Returns the number of key/value mappings in this map. If the map contains more thanInteger.MAX_VALUE
elements, returnsInteger.MAX_VALUE
. -
isEmpty
public boolean isEmpty() -
firstDoubleKey
public double firstDoubleKey()Returns the first key of this map in iteration order.- Specified by:
firstDoubleKey
in interfaceDouble2CharSortedMap
- Returns:
- the first key in iteration order.
- See Also:
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lastDoubleKey
public double lastDoubleKey()Returns the last key of this map in iteration order.- Specified by:
lastDoubleKey
in interfaceDouble2CharSortedMap
- Returns:
- the last key in iteration order.
- See Also:
-
tailMap
Returns a view of the portion of this sorted map whose keys are greater than or equal tofromKey
.- Specified by:
tailMap
in interfaceDouble2CharSortedMap
- See Also:
- Implementation Specification:
- This implementation just throws an
UnsupportedOperationException
.
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headMap
Returns a view of the portion of this sorted map whose keys are strictly less thantoKey
.- Specified by:
headMap
in interfaceDouble2CharSortedMap
- See Also:
- Implementation Specification:
- This implementation just throws an
UnsupportedOperationException
.
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subMap
Returns a view of the portion of this sorted map whose keys range fromfromKey
, inclusive, totoKey
, exclusive.- Specified by:
subMap
in interfaceDouble2CharSortedMap
- See Also:
- Implementation Specification:
- This implementation just throws an
UnsupportedOperationException
.
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comparator
Returns the comparator associated with this sorted set, or null if it uses its keys' natural ordering.- Specified by:
comparator
in interfaceDouble2CharSortedMap
- Specified by:
comparator
in interfaceSortedMap<Double,
Character> - See Also:
- Implementation Specification:
- This implementation just returns
null
.
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double2CharEntrySet
Description copied from interface:Double2CharSortedMap
Returns a type-specific sorted-set view of the mappings contained in this map.- Specified by:
double2CharEntrySet
in interfaceDouble2CharMap
- Specified by:
double2CharEntrySet
in interfaceDouble2CharSortedMap
- Returns:
- a type-specific sorted-set view of the mappings contained in this map.
- See Also:
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keySet
Description copied from class:AbstractDouble2CharSortedMap
Returns a type-specific-set view of the keys of this map.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.The view is backed by the sorted 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.- Specified by:
keySet
in interfaceDouble2CharMap
- Specified by:
keySet
in interfaceDouble2CharSortedMap
- Specified by:
keySet
in interfaceMap<Double,
Character> - Specified by:
keySet
in interfaceSortedMap<Double,
Character> - Overrides:
keySet
in classAbstractDouble2CharSortedMap
- Returns:
- a sorted set view of the keys of this map; it may be safely cast to a type-specific interface.
- See Also:
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values
Description copied from class:AbstractDouble2CharSortedMap
Returns a type-specific-set view of the values of this map.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.The view is backed by the sorted 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.- Specified by:
values
in interfaceDouble2CharMap
- Specified by:
values
in interfaceDouble2CharSortedMap
- Specified by:
values
in interfaceMap<Double,
Character> - Specified by:
values
in interfaceSortedMap<Double,
Character> - Overrides:
values
in classAbstractDouble2CharSortedMap
- Returns:
- a type-specific collection view of the values contained in this map.
- See Also:
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trim
public boolean trim()Rehashes the map, 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 map.
- See Also:
-
trim
public boolean trim(int n) Rehashes this map 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 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.
- Parameters:
n
- the threshold for the trimming.- Returns:
- true if there was enough memory to trim the map.
- See Also:
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clone
Returns a deep copy of this map.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.
- Returns:
- a deep copy of this map.
-
hashCode
public int hashCode()Returns a hash code for this map. 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.
-