com.fr.stable.collections.map

类 LongMap<V>

java.lang.Object

com.fr.stable.collections.map.LongMap<V>

所有已实现的接口:

java.lang.Iterable<LongMap.Entry<V>>

public class LongMap<V>
extends java.lang.Object
implements java.lang.Iterable<LongMap.Entry<V>>

An unordered map that uses long keys. This implementation is a cuckoo hash map using 3 hashes, random walking, and a small stash for problematic keys. Null values are allowed. No allocation is done except when growing the table size.

This map performs very fast get, containsKey, and remove (typically O(1), worst case O(log(n))). Put may be a bit slower, depending on hash collisions. Load factors greater than 0.91 greatly increase the chances the map will have to rehash to the next higher POT size.

作者:

Nathan Sweet

嵌套类概要

嵌套类

限定符和类型	类和说明
static class	LongMap.Entries<V>
static class	LongMap.Entry<V>
static class	LongMap.Keys
static class	LongMap.Values<V>

字段概要

字段

限定符和类型	字段和说明
int	size

构造器概要

构造器

构造器和说明
LongMap() Creates a new map with an initial capacity of 51 and a load factor of 0.8.
LongMap(int initialCapacity) Creates a new map with a load factor of 0.8.
LongMap(int initialCapacity, float loadFactor) Creates a new map with the specified initial capacity and load factor.
LongMap(LongMap<? extends V> map) Creates a new map identical to the specified map.

方法概要

方法

限定符和类型	方法和说明
void	clear()
void	clear(int maximumCapacity) Clears the map and reduces the size of the backing arrays to be the specified capacity if they are larger.
boolean	containsKey(long key)
boolean	containsValue(java.lang.Object value, boolean identity) Returns true if the specified value is in the map.
void	ensureCapacity(int additionalCapacity) Increases the size of the backing array to accommodate the specified number of additional items.
LongMap.Entries<V>	entries() Returns an iterator for the entries in the map.
boolean	equals(java.lang.Object obj)
long	findKey(java.lang.Object value, boolean identity, long notFound) Returns the key for the specified value, or notFound if it is not in the map.
V	get(long key)
V	get(long key, V defaultValue)
int	hashCode()
java.util.Iterator<LongMap.Entry<V>>	iterator()
LongMap.Keys	keys() Returns an iterator for the keys in the map.
V	put(long key, V value)
void	putAll(LongMap<V> map)
V	remove(long key)
void	shrink(int maximumCapacity) Reduces the size of the backing arrays to be the specified capacity or less.
java.lang.String	toString()
LongMap.Values<V>	values() Returns an iterator for the values in the map.

从类继承的方法 java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

字段详细资料

size

public int size

构造器详细资料

LongMap

public LongMap()

Creates a new map with an initial capacity of 51 and a load factor of 0.8.

LongMap

public LongMap(int initialCapacity)

Creates a new map with a load factor of 0.8.

参数:

initialCapacity - If not a power of two, it is increased to the next nearest power of two.

LongMap

public LongMap(int initialCapacity,
       float loadFactor)

Creates a new map with the specified initial capacity and load factor. This map will hold initialCapacity items before growing the backing table.

参数:

initialCapacity - If not a power of two, it is increased to the next nearest power of two.

LongMap

public LongMap(LongMap<? extends V> map)

Creates a new map identical to the specified map.

方法详细资料

put

public V put(long key,
    V value)

putAll

public void putAll(LongMap<V> map)

get

public V get(long key)

get

public V get(long key,
    V defaultValue)

remove

public V remove(long key)

shrink

public void shrink(int maximumCapacity)

Reduces the size of the backing arrays to be the specified capacity or less. If the capacity is already less, nothing is done. If the map contains more items than the specified capacity, the next highest power of two capacity is used instead.

clear

public void clear(int maximumCapacity)

Clears the map and reduces the size of the backing arrays to be the specified capacity if they are larger.

clear

public void clear()

containsValue

public boolean containsValue(java.lang.Object value,
                    boolean identity)

Returns true if the specified value is in the map. Note this traverses the entire map and compares every value, which may be an expensive operation.

containsKey

public boolean containsKey(long key)

findKey

public long findKey(java.lang.Object value,
           boolean identity,
           long notFound)

Returns the key for the specified value, or notFound if it is not in the map. Note this traverses the entire map and compares every value, which may be an expensive operation.

参数:

identity - If true, uses == to compare the specified value with values in the map. If false, uses equals(Object).

ensureCapacity

public void ensureCapacity(int additionalCapacity)

Increases the size of the backing array to accommodate the specified number of additional items. Useful before adding many items to avoid multiple backing array resizes.

hashCode

public int hashCode()

覆盖:

hashCode 在类中 java.lang.Object

equals

public boolean equals(java.lang.Object obj)

覆盖:

equals 在类中 java.lang.Object

toString

public java.lang.String toString()

覆盖:

toString 在类中 java.lang.Object

iterator

public java.util.Iterator<LongMap.Entry<V>> iterator()

指定者:

iterator 在接口中 java.lang.Iterable<LongMap.Entry<V>>

entries

public LongMap.Entries<V> entries()

Returns an iterator for the entries in the map. Remove is supported. Note that the same iterator instance is returned each time this method is called. Use the LongMap.Entries constructor for nested or multithreaded iteration.

values

public LongMap.Values<V> values()

Returns an iterator for the values in the map. Remove is supported. Note that the same iterator instance is returned each time this method is called. Use the LongMap.Entries constructor for nested or multithreaded iteration.

keys

public LongMap.Keys keys()

Returns an iterator for the keys in the map. Remove is supported. Note that the same iterator instance is returned each time this method is called. Use the LongMap.Entries constructor for nested or multithreaded iteration.