it.unimi.dsi.fastutil.chars
Class Char2LongLinkedOpenHashMap

java.lang.Object
  extended by it.unimi.dsi.fastutil.chars.AbstractChar2LongFunction
      extended by it.unimi.dsi.fastutil.chars.AbstractChar2LongMap
          extended by it.unimi.dsi.fastutil.chars.AbstractChar2LongSortedMap
              extended by it.unimi.dsi.fastutil.chars.Char2LongLinkedOpenHashMap
All Implemented Interfaces:
Char2LongFunction, Char2LongMap, Char2LongSortedMap, Function<Character,Long>, Hash, Serializable, Cloneable, Map<Character,Long>, SortedMap<Character,Long>

public class Char2LongLinkedOpenHashMap
extends AbstractChar2LongSortedMap
implements Serializable, Cloneable, Hash

A type-specific linked hash map with with a fast, small-footprint implementation.

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.

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 set 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 AbstractChar2LongSortedMap.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 set, 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:
Hash, HashCommon, Serialized Form

Nested Class Summary
 
Nested classes/interfaces inherited from class it.unimi.dsi.fastutil.chars.AbstractChar2LongSortedMap
AbstractChar2LongSortedMap.KeySetIterator, AbstractChar2LongSortedMap.ValuesCollection, AbstractChar2LongSortedMap.ValuesIterator
 
Nested classes/interfaces inherited from class it.unimi.dsi.fastutil.chars.AbstractChar2LongMap
AbstractChar2LongMap.BasicEntry
 
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.Hash
Hash.Strategy<K>
 
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.chars.Char2LongSortedMap
Char2LongSortedMap.FastSortedEntrySet
 
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.chars.Char2LongMap
Char2LongMap.Entry, Char2LongMap.FastEntrySet
 
Field Summary
protected  Char2LongSortedMap.FastSortedEntrySet 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  char[] key
          The array of keys.
protected  CharSortedSet 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 n
          The current table size.
static long serialVersionUID
           
protected  int size
          Number of entries in the set.
protected  boolean[] used
          The array telling whether a position is used.
protected  long[] value
          The array of values.
protected  LongCollection values
          Cached collection of values.
 
Fields inherited from class it.unimi.dsi.fastutil.chars.AbstractChar2LongFunction
defRetValue
 
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
 
Constructor Summary
Char2LongLinkedOpenHashMap()
          Creates a new hash map with initial expected Hash.DEFAULT_INITIAL_SIZE entries and Hash.DEFAULT_LOAD_FACTOR as load factor.
Char2LongLinkedOpenHashMap(char[] k, long[] v)
          Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor using the elements of two parallel arrays.
Char2LongLinkedOpenHashMap(char[] k, long[] v, float f)
          Creates a new hash map using the elements of two parallel arrays.
Char2LongLinkedOpenHashMap(Char2LongMap m)
          Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given type-specific one.
Char2LongLinkedOpenHashMap(Char2LongMap m, float f)
          Creates a new hash map copying a given type-specific one.
Char2LongLinkedOpenHashMap(int expected)
          Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor.
Char2LongLinkedOpenHashMap(int expected, float f)
          Creates a new hash map.
Char2LongLinkedOpenHashMap(Map<? extends Character,? extends Long> m)
          Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given one.
Char2LongLinkedOpenHashMap(Map<? extends Character,? extends Long> m, float f)
          Creates a new hash map copying a given one.
 
Method Summary
 long add(char k, long incr)
          Adds an increment to value currently associated with a key.
 Char2LongSortedMap.FastSortedEntrySet char2LongEntrySet()
          Returns a type-specific sorted-set view of the mappings contained in this map.
 void clear()
          Removes all associations from this function (optional operation).
 Char2LongLinkedOpenHashMap clone()
          Returns a deep copy of this map.
 CharComparator comparator()
          Returns the comparator associated with this sorted set, or null if it uses its keys' natural ordering.
 boolean containsKey(char k)
          Checks whether the given value is contained in AbstractChar2LongMap.keySet().
 boolean containsValue(long v)
          Checks whether the given value is contained in AbstractChar2LongMap.values().
 char firstCharKey()
          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.
 long get(char k)
          Returns the value to which the given key is mapped.
 Long get(Character ok)
           
 long getAndMoveToFirst(char 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.
 long getAndMoveToLast(char 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.
 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.
 Char2LongSortedMap headMap(char to)
          Returns a view of the portion of this sorted map whose keys are strictly less than toKey.
 boolean isEmpty()
           
 CharSortedSet keySet()
          Returns a type-specific-sorted-set view of the keys of this map.
 char lastCharKey()
          Returns the last key of this map in iteration order.
 Long put(Character ok, Long ov)
          Delegates to the corresponding type-specific method, taking care of returning null on a missing key.
 long put(char k, long v)
          Adds a pair to the map.
 long putAndMoveToFirst(char k, long v)
          Adds a pair to the map; if the key is already present, it is moved to the first position of the iteration order.
 long putAndMoveToLast(char k, long v)
          Adds a pair to the map; if the key is already present, it is moved to the last position of the iteration order.
 boolean rehash()
          Deprecated. A no-op.
protected  void rehash(int newN)
          Resizes the map.
 long remove(char k)
          Removes the mapping with the given key.
 Long remove(Object ok)
          Delegates to the corresponding type-specific method, taking care of returning null on a missing key.
 long removeFirstLong()
          Removes the mapping associated with the first key in iteration order.
 long removeLastLong()
          Removes the mapping associated with the last key in iteration order.
protected  int 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 intended number of keys in this function, or -1 if no such number exists.
 Char2LongSortedMap subMap(char from, char to)
          Returns a view of the portion of this sorted map whose keys range from fromKey, inclusive, to toKey, exclusive.
 Char2LongSortedMap tailMap(char 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.
 LongCollection values()
          Returns a type-specific collection view of the values contained in this map.
 
Methods inherited from class it.unimi.dsi.fastutil.chars.AbstractChar2LongSortedMap
entrySet, firstKey, headMap, lastKey, subMap, tailMap
 
Methods inherited from class it.unimi.dsi.fastutil.chars.AbstractChar2LongMap
containsValue, equals, putAll, toString
 
Methods inherited from class it.unimi.dsi.fastutil.chars.AbstractChar2LongFunction
containsKey, defaultReturnValue, defaultReturnValue, get
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface it.unimi.dsi.fastutil.chars.Char2LongFunction
defaultReturnValue, defaultReturnValue
 
Methods inherited from interface it.unimi.dsi.fastutil.Function
containsKey, get
 
Methods inherited from interface java.util.Map
containsKey, containsValue, equals, get, putAll
 

Field Detail

serialVersionUID

public static final long serialVersionUID
See Also:
Constant Field Values

key

protected transient char[] key
The array of keys.


value

protected transient long[] value
The array of values.


used

protected transient boolean[] used
The array telling whether a position is used.


f

protected final float f
The acceptable load factor.


n

protected transient int n
The current table size.


maxFill

protected transient int maxFill
Threshold after which we rehash. It must be the table size times f.


mask

protected transient int mask
The mask for wrapping a position counter.


size

protected int size
Number of entries in the set.


entries

protected transient volatile Char2LongSortedMap.FastSortedEntrySet entries
Cached set of entries.


keys

protected transient volatile CharSortedSet keys
Cached set of keys.


values

protected transient volatile LongCollection values
Cached collection of values.


first

protected transient int first
The index of the first entry in iteration order. It is valid iff size is nonzero; otherwise, it contains -1.


last

protected transient int last
The index of the last entry in iteration order. It is valid iff size is nonzero; otherwise, it contains -1.


link

protected transient long[] link
For each entry, the next and the previous entry in iteration order, stored as ((prev & 0xFFFFFFFFL) << 32) | (next & 0xFFFFFFFFL). The first entry contains predecessor -1, and the last entry contains successor -1.

Constructor Detail

Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap(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 set.
f - the load factor.

Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap(int expected)
Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor.

Parameters:
expected - the expected number of elements in the hash map.

Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap()
Creates a new hash map with initial expected Hash.DEFAULT_INITIAL_SIZE entries and Hash.DEFAULT_LOAD_FACTOR as load factor.


Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap(Map<? extends Character,? extends Long> m,
                                  float f)
Creates a new hash map copying a given one.

Parameters:
m - a Map to be copied into the new hash map.
f - the load factor.

Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap(Map<? extends Character,? extends Long> m)
Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given one.

Parameters:
m - a Map to be copied into the new hash map.

Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap(Char2LongMap m,
                                  float f)
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.

Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap(Char2LongMap m)
Creates a new hash map with Hash.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.

Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap(char[] k,
                                  long[] 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 - if k and v have different lengths.

Char2LongLinkedOpenHashMap

public Char2LongLinkedOpenHashMap(char[] k,
                                  long[] v)
Creates a new hash map with Hash.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 - if k and v have different lengths.
Method Detail

put

public long put(char k,
                long v)
Description copied from interface: Char2LongFunction
Adds a pair to the map.

Specified by:
put in interface Char2LongFunction
Overrides:
put in class AbstractChar2LongFunction
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:
Function.put(Object,Object)

put

public Long put(Character ok,
                Long ov)
Description copied from class: AbstractChar2LongFunction
Delegates to the corresponding type-specific method, taking care of returning 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.

Specified by:
put in interface Function<Character,Long>
Specified by:
put in interface Map<Character,Long>
Overrides:
put in class AbstractChar2LongFunction
Parameters:
ok - the key.
ov - the value.
Returns:
the old value, or null if no value was present for the given key.
See Also:
Map.put(Object,Object)

add

public long add(char k,
                long 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.

shiftKeys

protected final int shiftKeys(int pos)
Shifts left entries with the specified hash code, starting at the specified position, and empties the resulting free entry.

Parameters:
pos - a starting position.
Returns:
the position cleared by the shifting process.

remove

public long remove(char k)
Description copied from interface: Char2LongFunction
Removes the mapping with the given key.

Specified by:
remove in interface Char2LongFunction
Overrides:
remove in class AbstractChar2LongFunction
Returns:
the old value, or the default return value if no value was present for the given key.
See Also:
Function.remove(Object)

remove

public Long remove(Object ok)
Description copied from class: AbstractChar2LongFunction
Delegates to the corresponding type-specific method, taking care of returning 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.

Specified by:
remove in interface Function<Character,Long>
Specified by:
remove in interface Map<Character,Long>
Overrides:
remove in class AbstractChar2LongFunction
Returns:
the old value, or null if no value was present for the given key.
See Also:
Map.remove(Object)

removeFirstLong

public long removeFirstLong()
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.

removeLastLong

public long removeLastLong()
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.

getAndMoveToFirst

public long getAndMoveToFirst(char 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.

getAndMoveToLast

public long getAndMoveToLast(char 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.

putAndMoveToFirst

public long putAndMoveToFirst(char k,
                              long 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.

putAndMoveToLast

public long putAndMoveToLast(char k,
                             long 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.

get

public Long get(Character ok)

get

public long get(char k)
Description copied from interface: Char2LongFunction
Returns the value to which the given key is mapped.

Specified by:
get in interface Char2LongFunction
Parameters:
k - the key.
Returns:
the corresponding value, or the default return value if no value was present for the given key.
See Also:
Function.get(Object)

containsKey

public boolean containsKey(char k)
Description copied from class: AbstractChar2LongMap
Checks whether the given value is contained in AbstractChar2LongMap.keySet().

Specified by:
containsKey in interface Char2LongFunction
Overrides:
containsKey in class AbstractChar2LongMap
See Also:
Function.containsKey(Object)

containsValue

public boolean containsValue(long v)
Description copied from class: AbstractChar2LongMap
Checks whether the given value is contained in AbstractChar2LongMap.values().

Specified by:
containsValue in interface Char2LongMap
Overrides:
containsValue in class AbstractChar2LongMap
See Also:
Map.containsValue(Object)

clear

public void clear()
Description copied from interface: Function
Removes all associations from this function (optional operation).

Specified by:
clear in interface Function<Character,Long>
Specified by:
clear in interface Map<Character,Long>
Overrides:
clear in class AbstractChar2LongFunction
See Also:
Map.clear()

size

public int size()
Description copied from interface: Function
Returns the intended number of keys in this function, or -1 if no such number exists.

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.

Specified by:
size in interface Function<Character,Long>
Specified by:
size in interface Map<Character,Long>
Returns:
the intended number of keys in this function, or -1 if that number is not available.

isEmpty

public boolean isEmpty()
Specified by:
isEmpty in interface Map<Character,Long>
Overrides:
isEmpty in class AbstractChar2LongMap

growthFactor

@Deprecated
public void growthFactor(int growthFactor)
Deprecated. Since fastutil 6.1.0, hash tables are doubled when they are too full.

A no-op for backward compatibility.

Parameters:
growthFactor - unused.

growthFactor

@Deprecated
public int growthFactor()
Deprecated. Since fastutil 6.1.0, hash tables are doubled when they are too full.

Gets the growth factor (2).

Returns:
the growth factor of this set, which is fixed (2).
See Also:
growthFactor(int)

fixPointers

protected void fixPointers(int i)
Modifies the link vector so that the given entry is removed.

If the given entry is the first or the last one, this method will complete in constant time; otherwise, it will have to search for the given entry.

Parameters:
i - the index of an entry.

fixPointers

protected void fixPointers(int s,
                           int d)
Modifies the link vector for a shift from s to d.

If the given entry is the first or the last one, this method will complete in constant time; otherwise, it will have to search for the given entry.

Parameters:
s - the source position.
d - the destination position.

firstCharKey

public char firstCharKey()
Returns the first key of this map in iteration order.

Specified by:
firstCharKey in interface Char2LongSortedMap
Returns:
the first key in iteration order.
See Also:
SortedMap.firstKey()

lastCharKey

public char lastCharKey()
Returns the last key of this map in iteration order.

Specified by:
lastCharKey in interface Char2LongSortedMap
Returns:
the last key in iteration order.
See Also:
SortedMap.lastKey()

comparator

public CharComparator comparator()
Description copied from interface: Char2LongSortedMap
Returns the comparator associated with this sorted set, or null if it uses its keys' natural ordering.

Note that this specification strengthens the one given in SortedMap.comparator().

Specified by:
comparator in interface Char2LongSortedMap
Specified by:
comparator in interface SortedMap<Character,Long>
See Also:
SortedMap.comparator()

tailMap

public Char2LongSortedMap tailMap(char from)
Description copied from interface: Char2LongSortedMap
Returns a view of the portion of this sorted map whose keys are greater than or equal to fromKey.

Specified by:
tailMap in interface Char2LongSortedMap
See Also:
SortedMap.tailMap(Object)

headMap

public Char2LongSortedMap headMap(char to)
Description copied from interface: Char2LongSortedMap
Returns a view of the portion of this sorted map whose keys are strictly less than toKey.

Specified by:
headMap in interface Char2LongSortedMap
See Also:
SortedMap.headMap(Object)

subMap

public Char2LongSortedMap subMap(char from,
                                 char to)
Description copied from interface: Char2LongSortedMap
Returns a view of the portion of this sorted map whose keys range from fromKey, inclusive, to toKey, exclusive.

Specified by:
subMap in interface Char2LongSortedMap
See Also:
SortedMap.subMap(Object,Object)

char2LongEntrySet

public Char2LongSortedMap.FastSortedEntrySet char2LongEntrySet()
Description copied from interface: Char2LongSortedMap
Returns a type-specific sorted-set view of the mappings contained in this map. Note that this specification strengthens the one given in the corresponding type-specific unsorted map.

Specified by:
char2LongEntrySet in interface Char2LongMap
Specified by:
char2LongEntrySet in interface Char2LongSortedMap
Returns:
a type-specific sorted-set view of the mappings contained in this map.
See Also:
Char2LongSortedMap.entrySet()

keySet

public CharSortedSet keySet()
Description copied from class: AbstractChar2LongSortedMap
Returns a type-specific-sorted-set view of the keys of this map.

The view is backed by the sorted set returned by AbstractChar2LongSortedMap.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 interface Char2LongMap
Specified by:
keySet in interface Char2LongSortedMap
Specified by:
keySet in interface Map<Character,Long>
Specified by:
keySet in interface SortedMap<Character,Long>
Overrides:
keySet in class AbstractChar2LongSortedMap
Returns:
a sorted set view of the keys of this map; it may be safely cast to a type-specific interface.
See Also:
Map.keySet()

values

public LongCollection values()
Description copied from class: AbstractChar2LongSortedMap
Returns a type-specific collection view of the values contained in this map.

The view is backed by the sorted set returned by AbstractChar2LongSortedMap.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 interface Char2LongMap
Specified by:
values in interface Char2LongSortedMap
Specified by:
values in interface Map<Character,Long>
Specified by:
values in interface SortedMap<Character,Long>
Overrides:
values in class AbstractChar2LongSortedMap
Returns:
a type-specific collection view of the values contained in this map.
See Also:
Map.values()

rehash

@Deprecated
public boolean rehash()
Deprecated. A no-op.

A no-op for backward compatibility. The kind of tables implemented by this class never need rehashing.

If you need to reduce the table size to fit exactly this set, use trim().

Returns:
true.
See Also:
trim()

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(int)

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,size()) 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.

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:
trim()

rehash

protected void rehash(int newN)
Resizes the map.

This method implements the basic rehashing strategy, and may be overriden 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.

Parameters:
newN - the new size

clone

public Char2LongLinkedOpenHashMap 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.

Overrides:
clone in class Object
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. Since 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.

Specified by:
hashCode in interface Map<Character,Long>
Overrides:
hashCode in class AbstractChar2LongMap
Returns:
a hash code for this map.


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