it.unimi.dsi.fastutil.ints

Class Int2ObjectLinkedOpenHashMap<V>

java.lang.Object

it.unimi.dsi.fastutil.ints.AbstractInt2ObjectFunction<V>

it.unimi.dsi.fastutil.ints.AbstractInt2ObjectMap<V>

it.unimi.dsi.fastutil.ints.AbstractInt2ObjectSortedMap<V>

it.unimi.dsi.fastutil.ints.Int2ObjectLinkedOpenHashMap<V>

All Implemented Interfaces:

Function<Integer,V>, Hash, Int2ObjectFunction<V>, Int2ObjectMap<V>, Int2ObjectSortedMap<V>, Serializable, Cloneable, Map<Integer,V>, SortedMap<Integer,V>

public class Int2ObjectLinkedOpenHashMap<V>
extends AbstractInt2ObjectSortedMap<V>
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 AbstractInt2ObjectSortedMap.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.ints.AbstractInt2ObjectSortedMap

AbstractInt2ObjectSortedMap.KeySetIterator<V>, AbstractInt2ObjectSortedMap.ValuesCollection, AbstractInt2ObjectSortedMap.ValuesIterator<V>

Nested classes/interfaces inherited from class it.unimi.dsi.fastutil.ints.AbstractInt2ObjectMap

AbstractInt2ObjectMap.BasicEntry<V>

Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.Hash

Hash.Strategy<K>

Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.ints.Int2ObjectSortedMap

Int2ObjectSortedMap.FastSortedEntrySet<V>

Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.ints.Int2ObjectMap

Int2ObjectMap.Entry<V>, Int2ObjectMap.FastEntrySet<V>

Field Summary

Fields

Modifier and Type	Field and Description
protected Int2ObjectSortedMap.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 int[]	key The array of keys.
protected IntSortedSet	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 V[]	value The array of values.
protected ObjectCollection<V>	values Cached collection of values.

Fields inherited from class it.unimi.dsi.fastutil.ints.AbstractInt2ObjectFunction

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

Constructors

Constructor and Description
Int2ObjectLinkedOpenHashMap() Creates a new hash map with initial expected Hash.DEFAULT_INITIAL_SIZE entries and Hash.DEFAULT_LOAD_FACTOR as load factor.
Int2ObjectLinkedOpenHashMap(int expected) Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor.
Int2ObjectLinkedOpenHashMap(int[] k, V[] v) Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor using the elements of two parallel arrays.
Int2ObjectLinkedOpenHashMap(int[] k, V[] v, float f) Creates a new hash map using the elements of two parallel arrays.
Int2ObjectLinkedOpenHashMap(Int2ObjectMap<V> m) Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given type-specific one.
Int2ObjectLinkedOpenHashMap(Int2ObjectMap<V> m, float f) Creates a new hash map copying a given type-specific one.
Int2ObjectLinkedOpenHashMap(int expected, float f) Creates a new hash map.
Int2ObjectLinkedOpenHashMap(Map<? extends Integer,? extends V> m) Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given one.
Int2ObjectLinkedOpenHashMap(Map<? extends Integer,? extends V> m, float f) Creates a new hash map copying a given one.

Method Summary

Methods

Modifier and Type	Method and Description
void	clear() Removes all associations from this function (optional operation).
Int2ObjectLinkedOpenHashMap<V>	clone() Returns a deep copy of this map.
IntComparator	comparator() Returns the comparator associated with this sorted set, or null if it uses its keys' natural ordering.
boolean	containsKey(int k) Checks whether the given value is contained in AbstractInt2ObjectMap.keySet().
boolean	containsValue(Object v) Checks whether the given value is contained in AbstractInt2ObjectMap.values().
int	firstIntKey() 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(int k) Returns the value to which the given key is mapped.
V	get(Integer ok)
V	getAndMoveToFirst(int 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(int 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.
Int2ObjectSortedMap<V>	headMap(int to) Returns a view of the portion of this sorted map whose keys are strictly less than toKey.
Int2ObjectSortedMap.FastSortedEntrySet<V>	int2ObjectEntrySet() Returns a type-specific sorted-set view of the mappings contained in this map.
boolean	isEmpty()
IntSortedSet	keySet() Returns a type-specific-sorted-set view of the keys of this map.
int	lastIntKey() Returns the last key of this map in iteration order.
V	put(Integer ok, V ov) Delegates to the corresponding type-specific method, taking care of returning null on a missing key.
V	put(int k, V v) Adds a pair to the map.
V	putAndMoveToFirst(int 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(int 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.
boolean	rehash() Deprecated. A no-op.
protected void	rehash(int newN) Resizes the map.
V	remove(int k) Removes the mapping with the given key.
V	remove(Object ok) Delegates to the corresponding type-specific method, taking care of returning null on a missing key.
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.
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.
Int2ObjectSortedMap<V>	subMap(int from, int to) Returns a view of the portion of this sorted map whose keys range from fromKey, inclusive, to toKey, exclusive.
Int2ObjectSortedMap<V>	tailMap(int 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.
ObjectCollection<V>	values() Returns a type-specific collection view of the values contained in this map.

Methods inherited from class it.unimi.dsi.fastutil.ints.AbstractInt2ObjectSortedMap

entrySet, firstKey, headMap, lastKey, subMap, tailMap

Methods inherited from class it.unimi.dsi.fastutil.ints.AbstractInt2ObjectMap

equals, putAll, toString

Methods inherited from class it.unimi.dsi.fastutil.ints.AbstractInt2ObjectFunction

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.ints.Int2ObjectFunction

defaultReturnValue, defaultReturnValue

Methods inherited from interface it.unimi.dsi.fastutil.Function

containsKey, get

Methods inherited from interface java.util.Map

containsKey, equals, get, putAll

Field Detail

serialVersionUID

public static final long serialVersionUID

See Also:

Constant Field Values

key

protected transient int[] key

The array of keys.

value

protected transient V[] 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 Int2ObjectSortedMap.FastSortedEntrySet<V> entries

Cached set of entries.

keys

protected transient volatile IntSortedSet keys

Cached set of keys.

values

protected transient volatile ObjectCollection<V> 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

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap(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.

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap(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.

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap()

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

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap(Map<? extends Integer,? extends V> 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.

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap(Map<? extends Integer,? extends V> 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.

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap(Int2ObjectMap<V> 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.

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap(Int2ObjectMap<V> 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.

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap(int[] k,
                           V[] 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.

Int2ObjectLinkedOpenHashMap

public Int2ObjectLinkedOpenHashMap(int[] k,
                           V[] 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 V put(int k,
    V v)

Description copied from interface: Int2ObjectFunction

Adds a pair to the map.

Specified by:

put in interface Int2ObjectFunction<V>

Overrides:

put in class AbstractInt2ObjectFunction<V>

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 V put(Integer ok,
    V ov)

Description copied from class: AbstractInt2ObjectFunction

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<Integer,V>

Specified by:

put in interface Map<Integer,V>

Overrides:

put in class AbstractInt2ObjectFunction<V>

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)

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 V remove(int k)

Description copied from interface: Int2ObjectFunction

Removes the mapping with the given key.

Specified by:

remove in interface Int2ObjectFunction<V>

Overrides:

remove in class AbstractInt2ObjectFunction<V>

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 V remove(Object ok)

Description copied from class: AbstractInt2ObjectFunction

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<Integer,V>

Specified by:

remove in interface Map<Integer,V>

Overrides:

remove in class AbstractInt2ObjectFunction<V>

Returns:

the old value, or null if no value was present for the given key.

See Also:

Map.remove(Object)

removeFirst

public V removeFirst()

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.

removeLast

public V removeLast()

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 V getAndMoveToFirst(int 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 V getAndMoveToLast(int 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 V putAndMoveToFirst(int 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.

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 V putAndMoveToLast(int 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.

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 V get(Integer ok)

get

public V get(int k)

Description copied from interface: Int2ObjectFunction

Returns the value to which the given key is mapped.

Specified by:

get in interface Int2ObjectFunction<V>

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(int k)

Description copied from class: AbstractInt2ObjectMap

Checks whether the given value is contained in AbstractInt2ObjectMap.keySet().

Specified by:

containsKey in interface Int2ObjectFunction<V>

Overrides:

containsKey in class AbstractInt2ObjectMap<V>

See Also:

Function.containsKey(Object)

containsValue

public boolean containsValue(Object v)

Description copied from class: AbstractInt2ObjectMap

Checks whether the given value is contained in AbstractInt2ObjectMap.values().

Specified by:

containsValue in interface Map<Integer,V>

Overrides:

containsValue in class AbstractInt2ObjectMap<V>

clear

public void clear()

Description copied from interface: Function

Removes all associations from this function (optional operation).

Specified by:

clear in interface Function<Integer,V>

Specified by:

clear in interface Map<Integer,V>

Overrides:

clear in class AbstractInt2ObjectFunction<V>

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<Integer,V>

Specified by:

size in interface Map<Integer,V>

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<Integer,V>

Overrides:

isEmpty in class AbstractInt2ObjectMap<V>

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.

firstIntKey

public int firstIntKey()

Returns the first key of this map in iteration order.

Specified by:

firstIntKey in interface Int2ObjectSortedMap<V>

Returns:

the first key in iteration order.

See Also:

SortedMap.firstKey()

lastIntKey

public int lastIntKey()

Returns the last key of this map in iteration order.

Specified by:

lastIntKey in interface Int2ObjectSortedMap<V>

Returns:

the last key in iteration order.

See Also:

SortedMap.lastKey()

comparator

public IntComparator comparator()

Description copied from interface: Int2ObjectSortedMap

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 Int2ObjectSortedMap<V>

Specified by:

comparator in interface SortedMap<Integer,V>

See Also:

SortedMap.comparator()

tailMap

public Int2ObjectSortedMap<V> tailMap(int from)

Description copied from interface: Int2ObjectSortedMap

Returns a view of the portion of this sorted map whose keys are greater than or equal to fromKey.

Specified by:

tailMap in interface Int2ObjectSortedMap<V>

See Also:

SortedMap.tailMap(Object)

headMap

public Int2ObjectSortedMap<V> headMap(int to)

Description copied from interface: Int2ObjectSortedMap

Returns a view of the portion of this sorted map whose keys are strictly less than toKey.

Specified by:

headMap in interface Int2ObjectSortedMap<V>

See Also:

SortedMap.headMap(Object)

subMap

public Int2ObjectSortedMap<V> subMap(int from,
                            int to)

Description copied from interface: Int2ObjectSortedMap

Returns a view of the portion of this sorted map whose keys range from fromKey, inclusive, to toKey, exclusive.

Specified by:

subMap in interface Int2ObjectSortedMap<V>

See Also:

SortedMap.subMap(Object,Object)

int2ObjectEntrySet

public Int2ObjectSortedMap.FastSortedEntrySet<V> int2ObjectEntrySet()

Description copied from interface: Int2ObjectSortedMap

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:

int2ObjectEntrySet in interface Int2ObjectMap<V>

Specified by:

int2ObjectEntrySet in interface Int2ObjectSortedMap<V>

Returns:

a type-specific sorted-set view of the mappings contained in this map.

See Also:

Int2ObjectSortedMap.entrySet()

keySet

public IntSortedSet keySet()

Description copied from class: AbstractInt2ObjectSortedMap

Returns a type-specific-sorted-set view of the keys of this map.

The view is backed by the sorted set returned by AbstractInt2ObjectSortedMap.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 Int2ObjectMap<V>

Specified by:

keySet in interface Int2ObjectSortedMap<V>

Specified by:

keySet in interface Map<Integer,V>

Specified by:

keySet in interface SortedMap<Integer,V>

Overrides:

keySet in class AbstractInt2ObjectSortedMap<V>

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 ObjectCollection<V> values()

Description copied from class: AbstractInt2ObjectSortedMap

Returns a type-specific collection view of the values contained in this map.

The view is backed by the sorted set returned by AbstractInt2ObjectSortedMap.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 Int2ObjectMap<V>

Specified by:

values in interface Int2ObjectSortedMap<V>

Specified by:

values in interface Map<Integer,V>

Specified by:

values in interface SortedMap<Integer,V>

Overrides:

values in class AbstractInt2ObjectSortedMap<V>

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 Int2ObjectLinkedOpenHashMap<V> 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<Integer,V>

Overrides:

hashCode in class AbstractInt2ObjectMap<V>

Returns:

a hash code for this map.