it.unimi.dsi.fastutil.bytes
Class Byte2DoubleLinkedOpenHashMap

java.lang.Object
  it.unimi.dsi.fastutil.bytes.AbstractByte2DoubleFunction
      it.unimi.dsi.fastutil.bytes.AbstractByte2DoubleMap
          it.unimi.dsi.fastutil.bytes.AbstractByte2DoubleSortedMap
              it.unimi.dsi.fastutil.bytes.Byte2DoubleLinkedOpenHashMap

All Implemented Interfaces:

Byte2DoubleFunction, Byte2DoubleMap, Byte2DoubleSortedMap, Function<Byte,Double>, Hash, Serializable, Cloneable, Map<Byte,Double>, SortedMap<Byte,Double>

public class Byte2DoubleLinkedOpenHashMap
extends AbstractByte2DoubleSortedMap
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 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.

The enlargement speed is controlled by the growth factor, a positive number. If the growth factor is p, then the table is enlarged each time roughly by a factor 2^p/16. By default, p is Hash.DEFAULT_GROWTH_FACTOR, which means that the table is doubled at each enlargement, but one can easily set more or less aggressive policies by calling growthFactor(int) (note that the growth factor is not serialized: deserialized tables gets the default growth factor).

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 AbstractByte2DoubleSortedMap.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.

The iterators provided by the views of this class using are type-specific list iterators. However, creation of an iterator using a starting point is going to be very expensive, as the chosen starting point must be linearly searched for, unless it is AbstractByte2DoubleSortedMap.lastKey(), in which case the iterator is created in constant time.

Note that deletions in a linked table require scanning the list until the element to be removed is found. The only exceptions are the first element, the last element, and deletions performed using an iterator.

See Also:

Hash, HashCommon, Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class it.unimi.dsi.fastutil.bytes.AbstractByte2DoubleMap

AbstractByte2DoubleMap.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.bytes.Byte2DoubleSortedMap

Byte2DoubleSortedMap.FastSortedEntrySet

Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.bytes.Byte2DoubleMap

Byte2DoubleMap.Entry, Byte2DoubleMap.FastEntrySet

Field Summary

static long

serialVersionUID

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

Byte2DoubleLinkedOpenHashMap()
Creates a new hash map with Hash.DEFAULT_INITIAL_SIZE entries and Hash.DEFAULT_LOAD_FACTOR as load factor.

Byte2DoubleLinkedOpenHashMap(byte[] k, double[] v)
Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor using the elements of two parallel arrays.

Byte2DoubleLinkedOpenHashMap(byte[] k, double[] v, float f)
Creates a new hash map using the elements of two parallel arrays.

Byte2DoubleLinkedOpenHashMap(Byte2DoubleMap m)
Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given type-specific one.

Byte2DoubleLinkedOpenHashMap(Byte2DoubleMap m, float f)
Creates a new hash map copying a given type-specific one.

Byte2DoubleLinkedOpenHashMap(int n)
Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor.

Byte2DoubleLinkedOpenHashMap(int n, float f)
Creates a new hash map.

Byte2DoubleLinkedOpenHashMap(Map<? extends Byte,? extends Double> m)
Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given one.

Byte2DoubleLinkedOpenHashMap(Map<? extends Byte,? extends Double> m, float f)
Creates a new hash map copying a given one.

Method Summary

Byte2DoubleSortedMap.FastSortedEntrySet	byte2DoubleEntrySet() Returns a type-specific set view of the mappings contained in this map.
void	clear() Removes all associations from this function (optional operation).
Object	clone() Returns a deep copy of this map.
ByteComparator	comparator() Returns the comparator associated with this sorted set, or null if it uses its keys' natural ordering.
boolean	containsKey(byte k) Checks whether the given value is contained in AbstractByte2DoubleMap.keySet().
boolean	containsValue(double v) Checks whether the given value is contained in AbstractByte2DoubleMap.values().
byte	firstByteKey() Returns the first key of this map in iteration order.
double	get(byte k) Returns the value to which the given key is mapped.
Double	get(Byte ok)
int	growthFactor() Gets the growth factor.
void	growthFactor(int growthFactor) Sets the growth factor.
int	hashCode() Returns a hash code for this map.
Byte2DoubleSortedMap	headMap(byte to) Returns a view of the portion of this sorted map whose keys are strictly less than toKey.
boolean	isEmpty()
ByteSortedSet	keySet() Returns a type-specific-sorted-set view of the keys of this map.
byte	lastByteKey() Returns the last key of this map in iteration order.
double	put(byte k, double v) Adds a pair to the map.
Double	put(Byte ok, Double ov) Delegates to the corresponding type-specific method, taking care of returning null on a missing key.
boolean	rehash() Rehashes this map without changing the table size.
double	remove(byte k) Removes the mapping with the given key.
Double	remove(Object ok) Delegates to the corresponding type-specific method, taking care of returning null on a missing key.
int	size() Returns the intended number of keys in this function, or -1 if no such number exists.
Byte2DoubleSortedMap	subMap(byte from, byte to) Returns a view of the portion of this sorted map whose keys range from fromKey, inclusive, to toKey, exclusive.
Byte2DoubleSortedMap	tailMap(byte 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.
DoubleCollection	values() Returns a type-specific collection view of the values contained in this map.

Methods inherited from class it.unimi.dsi.fastutil.bytes.AbstractByte2DoubleSortedMap

entrySet, firstKey, headMap, lastKey, subMap, tailMap

Methods inherited from class it.unimi.dsi.fastutil.bytes.AbstractByte2DoubleMap

containsValue, equals, putAll, toString

Methods inherited from class it.unimi.dsi.fastutil.bytes.AbstractByte2DoubleFunction

containsKey, defaultReturnValue, defaultReturnValue, get

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface it.unimi.dsi.fastutil.bytes.Byte2DoubleFunction

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

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

Constructor Detail

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap(int n,
                                    float f)

Creates a new hash map. The actual table size is the least available prime greater than n/f.

Parameters:

n - the expected number of elements in the hash map.

f - the load factor.

See Also:

Hash.PRIMES

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap(int n)

Creates a new hash map with Hash.DEFAULT_LOAD_FACTOR as load factor.

Parameters:

n - the expected number of elements in the hash map.

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap()

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

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap(Map<? extends Byte,? extends Double> 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.

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap(Map<? extends Byte,? extends Double> 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.

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap(Byte2DoubleMap 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.

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap(Byte2DoubleMap 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.

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap(byte[] k,
                                    double[] 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.

Byte2DoubleLinkedOpenHashMap

public Byte2DoubleLinkedOpenHashMap(byte[] k,
                                    double[] 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

growthFactor

public void growthFactor(int growthFactor)

Sets the growth factor. Subsequent enlargements will increase the table size roughly by a multiplicative factor of 2^p/16.

Parameters:

growthFactor - the new growth factor; it must be positive.

growthFactor

public int growthFactor()

Gets the growth factor.

Returns:

the growth factor of this set.

See Also:

growthFactor(int)

put

public double put(byte k,
                  double v)

Description copied from interface: Byte2DoubleFunction

Adds a pair to the map.

Specified by:

put in interface Byte2DoubleFunction

Overrides:

put in class AbstractByte2DoubleFunction

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 Double put(Byte ok,
                  Double ov)

Description copied from class: AbstractByte2DoubleFunction

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<Byte,Double>

Specified by:

put in interface Map<Byte,Double>

Overrides:

put in class AbstractByte2DoubleFunction

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)

containsValue

public boolean containsValue(double v)

Description copied from class: AbstractByte2DoubleMap

Checks whether the given value is contained in AbstractByte2DoubleMap.values().

Specified by:

containsValue in interface Byte2DoubleMap

Overrides:

containsValue in class AbstractByte2DoubleMap

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<Byte,Double>

Specified by:

clear in interface Map<Byte,Double>

Overrides:

clear in class AbstractByte2DoubleFunction

See Also:

Map.clear()

firstByteKey

public byte firstByteKey()

Returns the first key of this map in iteration order.

Specified by:

firstByteKey in interface Byte2DoubleSortedMap

Returns:

the first key in iteration order.

See Also:

SortedMap.firstKey()

lastByteKey

public byte lastByteKey()

Returns the last key of this map in iteration order.

Specified by:

lastByteKey in interface Byte2DoubleSortedMap

Returns:

the last key in iteration order.

See Also:

SortedMap.lastKey()

comparator

public ByteComparator comparator()

Description copied from interface: Byte2DoubleSortedMap

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 Byte2DoubleSortedMap

Specified by:

comparator in interface SortedMap<Byte,Double>

See Also:

SortedMap.comparator()

tailMap

public Byte2DoubleSortedMap tailMap(byte from)

Description copied from interface: Byte2DoubleSortedMap

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

Specified by:

tailMap in interface Byte2DoubleSortedMap

See Also:

SortedMap.tailMap(Object)

headMap

public Byte2DoubleSortedMap headMap(byte to)

Description copied from interface: Byte2DoubleSortedMap

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

Specified by:

headMap in interface Byte2DoubleSortedMap

See Also:

SortedMap.headMap(Object)

subMap

public Byte2DoubleSortedMap subMap(byte from,
                                   byte to)

Description copied from interface: Byte2DoubleSortedMap

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

Specified by:

subMap in interface Byte2DoubleSortedMap

See Also:

SortedMap.subMap(Object,Object)

containsKey

public boolean containsKey(byte k)

Description copied from class: AbstractByte2DoubleMap

Checks whether the given value is contained in AbstractByte2DoubleMap.keySet().

Specified by:

containsKey in interface Byte2DoubleFunction

Overrides:

containsKey in class AbstractByte2DoubleMap

See Also:

Function.containsKey(Object)

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<Byte,Double>

Specified by:

size in interface Map<Byte,Double>

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<Byte,Double>

Overrides:

isEmpty in class AbstractByte2DoubleMap

get

public double get(byte k)

Description copied from interface: Byte2DoubleFunction

Returns the value to which the given key is mapped.

Specified by:

get in interface Byte2DoubleFunction

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)

remove

public double remove(byte k)

Description copied from interface: Byte2DoubleFunction

Removes the mapping with the given key.

Specified by:

remove in interface Byte2DoubleFunction

Overrides:

remove in class AbstractByte2DoubleFunction

Returns:

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

See Also:

Function.remove(Object)

get

public Double get(Byte ok)

remove

public Double remove(Object ok)

Description copied from class: AbstractByte2DoubleFunction

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<Byte,Double>

Specified by:

remove in interface Map<Byte,Double>

Overrides:

remove in class AbstractByte2DoubleFunction

Returns:

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

See Also:

Map.remove(Object)

byte2DoubleEntrySet

public Byte2DoubleSortedMap.FastSortedEntrySet byte2DoubleEntrySet()

Description copied from interface: Byte2DoubleMap

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

This method is necessary because there is no inheritance along type parameters: it is thus impossible to strengthen Byte2DoubleMap.entrySet() so that it returns an ObjectSet of objects of type Byte2DoubleMap.Entry (the latter makes it possible to access keys and values with type-specific methods).

Specified by:

byte2DoubleEntrySet in interface Byte2DoubleMap

Specified by:

byte2DoubleEntrySet in interface Byte2DoubleSortedMap

Returns:

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

See Also:

Byte2DoubleMap.entrySet()

keySet

public ByteSortedSet keySet()

Description copied from class: AbstractByte2DoubleSortedMap

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

The view is backed by the sorted set returned by AbstractByte2DoubleSortedMap.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 Byte2DoubleMap

Specified by:

keySet in interface Byte2DoubleSortedMap

Specified by:

keySet in interface Map<Byte,Double>

Overrides:

keySet in class AbstractByte2DoubleSortedMap

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 DoubleCollection values()

Description copied from class: AbstractByte2DoubleSortedMap

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

The view is backed by the sorted set returned by AbstractByte2DoubleSortedMap.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 Byte2DoubleMap

Specified by:

values in interface Byte2DoubleSortedMap

Specified by:

values in interface Map<Byte,Double>

Overrides:

values in class AbstractByte2DoubleSortedMap

Returns:

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

See Also:

Map.values()

rehash

public boolean rehash()

Rehashes this map without changing the table size.

This method should be called when the map underwent numerous deletions and insertions. In this case, free entries become rare, and unsuccessful searches require probing all entries. For reasonable load factors this method is linear in the number of entries. You will need as much additional free memory as that occupied by the table.

If you need to reduce the table siza to fit exactly this map, you must use trim().

Returns:

true if there was enough memory to rehash the map, false otherwise.

See Also:

trim()

trim

public boolean trim()

Rehashes the map, making the table as small as possible.

This method rehashes to the smallest size satisfying the load factor. It can be used when the map will not be changed anymore, so to optimize access speed (by collecting deleted entries) and size.

If the table size is already the minimum possible, this method does nothing. If you want to guarantee rehashing, use rehash().

Returns:

true if there was enough memory to trim the map.

See Also:

trim(int), rehash()

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()

clone

public Object 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<Byte,Double>

Overrides:

hashCode in class AbstractByte2DoubleMap

Returns:

a hash code for this map.