public class Long2ReferenceLinkedOpenHashMap<V> extends AbstractLong2ReferenceSortedMap<V> implements Serializable, 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.
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.
Hash,
HashCommon,
Serialized FormAbstractLong2ReferenceSortedMap.KeySetIterator<V>, AbstractLong2ReferenceSortedMap.ValuesCollection, AbstractLong2ReferenceSortedMap.ValuesIterator<V>AbstractLong2ReferenceMap.BasicEntry<V>, AbstractLong2ReferenceMap.BasicEntrySet<V>Hash.Strategy<K>Long2ReferenceSortedMap.FastSortedEntrySet<V>Long2ReferenceMap.Entry<V>, Long2ReferenceMap.FastEntrySet<V>| Modifier and Type | Field and Description |
|---|---|
protected boolean |
containsNullKey
Whether this map contains the key zero.
|
protected Long2ReferenceSortedMap.FastSortedEntrySet<V> |
entries
Cached set of entries.
|
protected float |
f
The acceptable load factor.
|
protected int |
first
The index of the first entry in iteration order.
|
protected long[] |
key
The array of keys.
|
protected LongSortedSet |
keys
Cached set of keys.
|
protected int |
last
The index of the last entry in iteration order.
|
protected long[] |
link
For each entry, the next and the previous entry in iteration order,
stored as
((prev & 0xFFFFFFFFL) << 32) | (next & 0xFFFFFFFFL). |
protected int |
mask
The mask for wrapping a position counter.
|
protected int |
maxFill
Threshold after which we rehash.
|
protected int |
minN
We never resize below this threshold, which is the construction-time {#n}.
|
protected int |
n
The current table size.
|
protected int |
size
Number of entries in the set (including the key zero, if present).
|
protected V[] |
value
The array of values.
|
protected ReferenceCollection<V> |
values
Cached collection of values.
|
defRetValueDEFAULT_GROWTH_FACTOR, DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR, FAST_LOAD_FACTOR, FREE, OCCUPIED, PRIMES, REMOVED, VERY_FAST_LOAD_FACTOR| Constructor and Description |
|---|
Long2ReferenceLinkedOpenHashMap()
Creates a new hash map with initial expected
Hash.DEFAULT_INITIAL_SIZE entries
and Hash.DEFAULT_LOAD_FACTOR as load factor. |
Long2ReferenceLinkedOpenHashMap(int expected)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor. |
Long2ReferenceLinkedOpenHashMap(int expected,
float f)
Creates a new hash map.
|
Long2ReferenceLinkedOpenHashMap(long[] k,
V[] v)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor using the elements of two parallel arrays. |
Long2ReferenceLinkedOpenHashMap(long[] k,
V[] v,
float f)
Creates a new hash map using the elements of two parallel arrays.
|
Long2ReferenceLinkedOpenHashMap(Long2ReferenceMap<V> m)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor copying a given type-specific one. |
Long2ReferenceLinkedOpenHashMap(Long2ReferenceMap<V> m,
float f)
Creates a new hash map copying a given type-specific one.
|
Long2ReferenceLinkedOpenHashMap(Map<? extends Long,? extends V> m)
Creates a new hash map with
Hash.DEFAULT_LOAD_FACTOR as load factor copying a given one. |
Long2ReferenceLinkedOpenHashMap(Map<? extends Long,? extends V> m,
float f)
Creates a new hash map copying a given one.
|
| Modifier and Type | Method and Description |
|---|---|
void |
clear()
Removes all of the mappings from this map (optional operation).
|
Long2ReferenceLinkedOpenHashMap<V> |
clone()
Returns a deep copy of this map.
|
LongComparator |
comparator()
Returns the comparator associated with this sorted set, or null if it uses its keys' natural ordering.
|
V |
compute(long k,
BiFunction<? super Long,? 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(long k,
LongFunction<? 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(long k,
BiFunction<? super Long,? 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(long k)
Returns true if this function contains a mapping for the specified key.
|
boolean |
containsValue(Object v) |
long |
firstLongKey()
Returns the first key of this map in iteration order.
|
protected void |
fixPointers(int i)
Modifies the
link vector so that the given entry is removed. |
protected void |
fixPointers(int s,
int d)
Modifies the
link vector for a shift from s to d. |
V |
get(long k)
Returns the value to which the given key is mapped.
|
V |
getAndMoveToFirst(long 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.
|
V |
getAndMoveToLast(long 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.
|
V |
getOrDefault(long 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.
|
Long2ReferenceSortedMap<V> |
headMap(long to)
Returns a view of the portion of this sorted map whose keys are strictly less than
toKey. |
boolean |
isEmpty() |
LongSortedSet |
keySet()
Returns a type-specific-set view of the keys of this map.
|
long |
lastLongKey()
Returns the last key of this map in iteration order.
|
Long2ReferenceSortedMap.FastSortedEntrySet<V> |
long2ReferenceEntrySet()
Returns a type-specific sorted-set view of the mappings contained in this map.
|
V |
merge(long k,
V v,
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(long k,
V v)
Adds a pair to the map (optional operation).
|
void |
putAll(Map<? extends Long,? extends V> m) |
V |
putAndMoveToFirst(long k,
V v)
Adds a pair to the map; if the key is already present, it is moved to the first position of the iteration order.
|
V |
putAndMoveToLast(long k,
V v)
Adds a pair to the map; if the key is already present, it is moved to the last position of the iteration order.
|
V |
putIfAbsent(long 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.
|
protected void |
rehash(int newN)
Rehashes the map.
|
V |
remove(long k)
Removes the mapping with the given key (optional operation).
|
boolean |
remove(long k,
Object v)
Removes the entry for the specified key only if it is currently mapped to the specified value.
|
V |
removeFirst()
Removes the mapping associated with the first key in iteration order.
|
V |
removeLast()
Removes the mapping associated with the last key in iteration order.
|
V |
replace(long k,
V v)
Replaces the entry for the specified key only if it is currently mapped to some value.
|
boolean |
replace(long k,
V oldValue,
V v)
Replaces the entry for the specified key only if currently mapped to the specified value.
|
protected void |
shiftKeys(int pos)
Shifts left entries with the specified hash code, starting at the specified position,
and empties the resulting free entry.
|
int |
size()
Returns the number of key/value mappings in this map.
|
Long2ReferenceSortedMap<V> |
subMap(long from,
long to)
Returns a view of the portion of this sorted map whose keys range from
fromKey, inclusive, to toKey, exclusive. |
Long2ReferenceSortedMap<V> |
tailMap(long from)
Returns a view of the portion of this sorted map whose keys are greater than or equal to
fromKey. |
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, defaultReturnValuefinalize, getClass, notify, notifyAll, wait, wait, waitentrySet, firstKey, headMap, lastKey, subMap, tailMapcompute, computeIfAbsent, computeIfAbsentPartial, computeIfPresent, containsKey, defaultReturnValue, defaultReturnValue, get, getOrDefault, merge, put, putIfAbsent, remove, remove, replace, replaceapplyequals, forEach, replaceAllprotected transient long[] key
protected transient V[] value
protected transient int mask
protected transient boolean containsNullKey
protected transient int first
size is nonzero; otherwise, it contains -1.protected transient int last
size is nonzero; otherwise, it contains -1.protected transient long[] link
((prev & 0xFFFFFFFFL) << 32) | (next & 0xFFFFFFFFL).
The first entry contains predecessor -1, and the last entry
contains successor -1.protected transient int n
protected transient int maxFill
f.protected final transient int minN
protected int size
protected final float f
protected transient Long2ReferenceSortedMap.FastSortedEntrySet<V> entries
protected transient LongSortedSet keys
protected transient ReferenceCollection<V> values
public Long2ReferenceLinkedOpenHashMap(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 Long2ReferenceLinkedOpenHashMap(int expected)
Hash.DEFAULT_LOAD_FACTOR as load factor.expected - the expected number of elements in the hash map.public Long2ReferenceLinkedOpenHashMap()
Hash.DEFAULT_INITIAL_SIZE entries
and Hash.DEFAULT_LOAD_FACTOR as load factor.public Long2ReferenceLinkedOpenHashMap(Map<? extends Long,? extends V> m, float f)
m - a Map to be copied into the new hash map.f - the load factor.public Long2ReferenceLinkedOpenHashMap(Map<? extends Long,? 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 Long2ReferenceLinkedOpenHashMap(Long2ReferenceMap<V> m, float f)
m - a type-specific map to be copied into the new hash map.f - the load factor.public Long2ReferenceLinkedOpenHashMap(Long2ReferenceMap<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 Long2ReferenceLinkedOpenHashMap(long[] 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.IllegalArgumentException - if k and v have different lengths.public Long2ReferenceLinkedOpenHashMap(long[] 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.IllegalArgumentException - if k and v have different lengths.public void putAll(Map<? extends Long,? extends V> m)
AbstractLong2ReferenceMappublic V put(long k, V v)
Long2ReferenceFunctionput in interface Long2ReferenceFunction<V>k - the key.v - the value.Function.put(Object,Object)protected final void shiftKeys(int pos)
pos - a starting position.public V remove(long k)
Long2ReferenceFunctionremove in interface Long2ReferenceFunction<V>k - the key.Function.remove(Object)public V removeFirst()
NoSuchElementException - is this map is empty.public V removeLast()
NoSuchElementException - is this map is empty.public V getAndMoveToFirst(long k)
k - the key.public V getAndMoveToLast(long k)
k - the key.public V putAndMoveToFirst(long k, V v)
k - the key.v - the value.public V putAndMoveToLast(long k, V v)
k - the key.v - the value.public V get(long k)
Long2ReferenceFunctionget in interface Long2ReferenceFunction<V>k - the key.Function.get(Object)public boolean containsKey(long k)
Long2ReferenceMapcontainsKey in interface Long2ReferenceFunction<V>containsKey in interface Long2ReferenceMap<V>containsKey in class AbstractLong2ReferenceMap<V>k - the key.key.Map.containsKey(Object)public boolean containsValue(Object v)
containsValue in interface Map<Long,V>containsValue in class AbstractLong2ReferenceMap<V>public V getOrDefault(long k, V defaultValue)
defaultValue if this
map contains no mapping for the key.getOrDefault in interface Long2ReferenceMap<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(long k, V v)
putIfAbsent in interface Long2ReferenceMap<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(long k,
Object v)
remove in interface Long2ReferenceMap<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(long k,
V oldValue,
V v)
replace in interface Long2ReferenceMap<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(long k, V v)
replace in interface Long2ReferenceMap<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(long k, LongFunction<? 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 Long2ReferenceMap<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(long k, BiFunction<? super Long,? super V,? extends V> remappingFunction)
computeIfPresent in interface Long2ReferenceMap<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(long k, BiFunction<? super Long,? 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 Long2ReferenceMap<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(long k, V v, 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 Long2ReferenceMap<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()
Long2ReferenceMapclear in interface Long2ReferenceMap<V>clear in interface Map<Long,V>Map.clear()public int size()
Long2ReferenceMapInteger.MAX_VALUE elements, returns Integer.MAX_VALUE.public boolean isEmpty()
protected void fixPointers(int i)
link vector so that the given entry is removed.
This method will complete in constant time.i - the index of an entry.protected void fixPointers(int s,
int d)
link vector for a shift from s to d.
This method will complete in constant time.
s - the source position.d - the destination position.public long firstLongKey()
firstLongKey in interface Long2ReferenceSortedMap<V>SortedMap.firstKey()public long lastLongKey()
lastLongKey in interface Long2ReferenceSortedMap<V>SortedMap.lastKey()public Long2ReferenceSortedMap<V> tailMap(long from)
fromKey.
Note that this specification strengthens the one given in SortedMap.tailMap(Object).
This implementation just throws an UnsupportedOperationException.
tailMap in interface Long2ReferenceSortedMap<V>SortedMap.tailMap(Object)public Long2ReferenceSortedMap<V> headMap(long to)
toKey.
Note that this specification strengthens the one given in SortedMap.headMap(Object).
This implementation just throws an UnsupportedOperationException.
headMap in interface Long2ReferenceSortedMap<V>SortedMap.headMap(Object)public Long2ReferenceSortedMap<V> subMap(long from, long to)
fromKey, inclusive, to toKey, exclusive.
Note that this specification strengthens the one given in SortedMap.subMap(Object,Object).
This implementation just throws an UnsupportedOperationException.
subMap in interface Long2ReferenceSortedMap<V>SortedMap.subMap(Object,Object)public LongComparator comparator()
Note that this specification strengthens the one given in SortedMap.comparator().
This implementation just returns null.
comparator in interface Long2ReferenceSortedMap<V>comparator in interface SortedMap<Long,V>SortedMap.comparator()public Long2ReferenceSortedMap.FastSortedEntrySet<V> long2ReferenceEntrySet()
Long2ReferenceSortedMapNote that this specification strengthens the one given in the corresponding type-specific unsorted map.
long2ReferenceEntrySet in interface Long2ReferenceMap<V>long2ReferenceEntrySet in interface Long2ReferenceSortedMap<V>Long2ReferenceSortedMap.entrySet()public LongSortedSet keySet()
AbstractLong2ReferenceSortedMapThe 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.
keySet in interface Long2ReferenceMap<V>keySet in interface Long2ReferenceSortedMap<V>keySet in interface Map<Long,V>keySet in interface SortedMap<Long,V>keySet in class AbstractLong2ReferenceSortedMap<V>Map.keySet()public ReferenceCollection<V> values()
AbstractLong2ReferenceSortedMapThe 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.
values in interface Long2ReferenceMap<V>values in interface Long2ReferenceSortedMap<V>values in interface Map<Long,V>values in interface SortedMap<Long,V>values in class AbstractLong2ReferenceSortedMap<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()protected void rehash(int newN)
This method implements the basic rehashing strategy, and may be overridden 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 Long2ReferenceLinkedOpenHashMap<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.Copyright © 2020. All rights reserved.