public class Char2ReferenceOpenHashMap<V> extends AbstractChar2ReferenceMap<V> 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 FormAbstractChar2ReferenceMap.BasicEntry<V>, AbstractChar2ReferenceMap.BasicEntrySet<V>Hash.Strategy<K>Char2ReferenceMap.Entry<V>, Char2ReferenceMap.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 |
|---|
Char2ReferenceOpenHashMap()
Creates a new hash map with initial expected
Hash.DEFAULT_INITIAL_SIZE entries and
Hash.DEFAULT_LOAD_FACTOR as load factor. |
Char2ReferenceOpenHashMap(char[] k,
V[] v)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor
using the elements of two parallel arrays. |
Char2ReferenceOpenHashMap(char[] k,
V[] v,
float f)
Creates a new hash map using the elements of two parallel arrays.
|
Char2ReferenceOpenHashMap(Char2ReferenceMap<V> m)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given type-specific one. |
Char2ReferenceOpenHashMap(Char2ReferenceMap<V> m,
float f)
Creates a new hash map copying a given type-specific one.
|
Char2ReferenceOpenHashMap(int expected)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor. |
Char2ReferenceOpenHashMap(int expected,
float f)
Creates a new hash map.
|
Char2ReferenceOpenHashMap(java.util.Map<? extends java.lang.Character,? extends V> m)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given one. |
Char2ReferenceOpenHashMap(java.util.Map<? extends java.lang.Character,? extends V> m,
float f)
Creates a new hash map copying a given one.
|
| Modifier and Type | Method and Description |
|---|---|
Char2ReferenceMap.FastEntrySet<V> |
char2ReferenceEntrySet()
Returns a type-specific set view of the mappings contained in this map.
|
void |
clear()
Removes all of the mappings from this map (optional operation).
|
Char2ReferenceOpenHashMap<V> |
clone()
Returns a deep copy of this map.
|
V |
compute(char k,
java.util.function.BiFunction<? super java.lang.Character,? super V,? extends V> remappingFunction)
Attempts to compute a mapping for the specified key and its current mapped
value (or
null if there is no current mapping). |
V |
computeIfAbsent(char k,
java.util.function.IntFunction<? extends V> 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.
|
V |
computeIfPresent(char k,
java.util.function.BiFunction<? super java.lang.Character,? super V,? extends V> 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(char k)
Returns true if this function contains a mapping for the specified key.
|
boolean |
containsValue(java.lang.Object v) |
V |
get(char k)
Returns the value to which the given key is mapped.
|
V |
getOrDefault(char k,
V 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() |
CharSet |
keySet()
Returns a type-specific-set view of the keys of this map.
|
V |
merge(char k,
V v,
java.util.function.BiFunction<? super V,? super V,? extends V> remappingFunction)
If the specified key is not already associated with a value or is associated
with null, associates it with the given non-null
value. |
V |
put(char k,
V v)
Adds a pair to the map (optional operation).
|
void |
putAll(java.util.Map<? extends java.lang.Character,? extends V> m) |
V |
putIfAbsent(char k,
V 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.
|
V |
remove(char k)
Removes the mapping with the given key (optional operation).
|
boolean |
remove(char k,
java.lang.Object v)
Removes the entry for the specified key only if it is currently mapped to the
specified value.
|
V |
replace(char k,
V v)
Replaces the entry for the specified key only if it is currently mapped to
some value.
|
boolean |
replace(char k,
V oldValue,
V 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.
|
ReferenceCollection<V> |
values()
Returns a type-specific-set view of the values of this map.
|
equals, toStringdefaultReturnValue, defaultReturnValuecompute, computeIfAbsent, computeIfAbsentPartial, computeIfPresent, containsKey, defaultReturnValue, defaultReturnValue, entrySet, get, getOrDefault, merge, put, putIfAbsent, remove, remove, replace, replaceapplypublic Char2ReferenceOpenHashMap(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 Char2ReferenceOpenHashMap(int expected)
Hash.DEFAULT_LOAD_FACTOR as load factor.expected - the expected number of elements in the hash map.public Char2ReferenceOpenHashMap()
Hash.DEFAULT_INITIAL_SIZE entries and
Hash.DEFAULT_LOAD_FACTOR as load factor.public Char2ReferenceOpenHashMap(java.util.Map<? extends java.lang.Character,? extends V> m, float f)
m - a Map to be copied into the new hash map.f - the load factor.public Char2ReferenceOpenHashMap(java.util.Map<? extends java.lang.Character,? extends V> m)
Hash.DEFAULT_LOAD_FACTOR as load factor
copying a given one.m - a Map to be copied into the new hash map.public Char2ReferenceOpenHashMap(Char2ReferenceMap<V> m, float f)
m - a type-specific map to be copied into the new hash map.f - the load factor.public Char2ReferenceOpenHashMap(Char2ReferenceMap<V> 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 Char2ReferenceOpenHashMap(char[] k,
V[] 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 Char2ReferenceOpenHashMap(char[] k,
V[] 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.Character,? extends V> m)
AbstractChar2ReferenceMapputAll in interface java.util.Map<java.lang.Character,V>putAll in class AbstractChar2ReferenceMap<V>public V put(char k, V v)
Char2ReferenceFunctionput in interface Char2ReferenceFunction<V>k - the key.v - the value.Function.put(Object,Object)public V remove(char k)
Char2ReferenceFunctionremove in interface Char2ReferenceFunction<V>k - the key.Function.remove(Object)public V get(char k)
Char2ReferenceFunctionget in interface Char2ReferenceFunction<V>k - the key.Function.get(Object)public boolean containsKey(char k)
Char2ReferenceMapcontainsKey in interface Char2ReferenceFunction<V>containsKey in interface Char2ReferenceMap<V>containsKey in class AbstractChar2ReferenceMap<V>k - the key.key.Map.containsKey(Object)public boolean containsValue(java.lang.Object v)
containsValue in interface java.util.Map<java.lang.Character,V>containsValue in class AbstractChar2ReferenceMap<V>public V getOrDefault(char k, V defaultValue)
defaultValue if this map contains no mapping for the key.getOrDefault in interface Char2ReferenceMap<V>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 V putIfAbsent(char k, V v)
putIfAbsent in interface Char2ReferenceMap<V>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(char k,
java.lang.Object v)
remove in interface Char2ReferenceMap<V>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(char k,
V oldValue,
V v)
replace in interface Char2ReferenceMap<V>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 V replace(char k, V v)
replace in interface Char2ReferenceMap<V>k - key with which the specified value is associated.v - value to be associated with the specified key.Map.replace(Object, Object)public V computeIfAbsent(char k, java.util.function.IntFunction<? extends V> 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 Char2ReferenceMap<V>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 V computeIfPresent(char k, java.util.function.BiFunction<? super java.lang.Character,? super V,? extends V> remappingFunction)
computeIfPresent in interface Char2ReferenceMap<V>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 V compute(char k, java.util.function.BiFunction<? super java.lang.Character,? super V,? extends V> 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 Char2ReferenceMap<V>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 V merge(char k, V v, java.util.function.BiFunction<? super V,? super V,? extends V> 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 Char2ReferenceMap<V>k - key with which the resulting value is to be associated.v - the non-null 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()
Char2ReferenceMapclear in interface Char2ReferenceMap<V>clear in interface java.util.Map<java.lang.Character,V>Map.clear()public int size()
Char2ReferenceMapInteger.MAX_VALUE elements, returns
Integer.MAX_VALUE.size in interface Char2ReferenceMap<V>size in interface java.util.Map<java.lang.Character,V>Size64public boolean isEmpty()
isEmpty in interface java.util.Map<java.lang.Character,V>isEmpty in class AbstractChar2ReferenceMap<V>public Char2ReferenceMap.FastEntrySet<V> char2ReferenceEntrySet()
Char2ReferenceMap
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).
char2ReferenceEntrySet in interface Char2ReferenceMap<V>Map.entrySet()public CharSet keySet()
AbstractChar2ReferenceMap
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 Char2ReferenceMap<V>keySet in interface java.util.Map<java.lang.Character,V>keySet in class AbstractChar2ReferenceMap<V>Map.keySet()public ReferenceCollection<V> values()
AbstractChar2ReferenceMap
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 Char2ReferenceMap<V>values in interface java.util.Map<java.lang.Character,V>values in class AbstractChar2ReferenceMap<V>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 Char2ReferenceOpenHashMap<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.
clone in class java.lang.Objectpublic 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.Character,V>hashCode in class AbstractChar2ReferenceMap<V>