Reference2ShortOpenHashMap (fastutil 6.4.1 API)

java.lang.Object
- it.unimi.dsi.fastutil.objects.AbstractReference2ShortFunction<K>
- - it.unimi.dsi.fastutil.objects.AbstractReference2ShortMap<K>
  - - it.unimi.dsi.fastutil.objects.Reference2ShortOpenHashMap<K>

All Implemented Interfaces:

Function<K,Short>, Hash, Reference2ShortFunction<K>, Reference2ShortMap<K>, Serializable, Cloneable, Map<K,Short>
```
public class Reference2ShortOpenHashMap<K>
extends AbstractReference2ShortMap<K>
implements Serializable, Cloneable, Hash
```
A type-specific hash map 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.
Warning: The implementation of this class has significantly changed in fastutil 6.1.0. Please read the comments about this issue in the section “Faster Hash Tables” of the overview.

See Also:
Hash, HashCommon, Serialized Form

Nested Class Summary
- Nested classes/interfaces inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2ShortMap
  AbstractReference2ShortMap.BasicEntry<K>
- Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.Hash
  Hash.Strategy<K>
- Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.objects.Reference2ShortMap
  Reference2ShortMap.Entry<K>, Reference2ShortMap.FastEntrySet<K>

Field Summary

Fields
Modifier and Type	Field and Description
`protected Reference2ShortMap.FastEntrySet<K>`	`entries` Cached set of entries.
`protected float`	`f` The acceptable load factor.
`protected K[]`	`key` The array of keys.
`protected ReferenceSet<K>`	`keys` Cached set of keys.
`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 short[]`	`value` The array of values.
`protected ShortCollection`	`values` Cached collection of values.

Fields inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2ShortFunction
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
`Reference2ShortOpenHashMap()` Creates a new hash map with initial expected `Hash.DEFAULT_INITIAL_SIZE` entries and `Hash.DEFAULT_LOAD_FACTOR` as load factor.
`Reference2ShortOpenHashMap(int expected)` Creates a new hash map with `Hash.DEFAULT_LOAD_FACTOR` as load factor.
`Reference2ShortOpenHashMap(int expected, float f)` Creates a new hash map.
`Reference2ShortOpenHashMap(K[] k, short[] v)` Creates a new hash map with `Hash.DEFAULT_LOAD_FACTOR` as load factor using the elements of two parallel arrays.
`Reference2ShortOpenHashMap(K[] k, short[] v, float f)` Creates a new hash map using the elements of two parallel arrays.
`Reference2ShortOpenHashMap(Map<? extends K,? extends Short> m)` Creates a new hash map with `Hash.DEFAULT_LOAD_FACTOR` as load factor copying a given one.
`Reference2ShortOpenHashMap(Map<? extends K,? extends Short> m, float f)` Creates a new hash map copying a given one.
`Reference2ShortOpenHashMap(Reference2ShortMap<K> m)` Creates a new hash map with `Hash.DEFAULT_LOAD_FACTOR` as load factor copying a given type-specific one.
`Reference2ShortOpenHashMap(Reference2ShortMap<K> m, float f)` Creates a new hash map copying a given type-specific one.

Method Summary

Methods
Modifier and Type	Method and Description
`short`	`add(K k, short incr)` Adds an increment to value currently associated with a key.
`void`	`clear()` Removes all associations from this function (optional operation).
`Reference2ShortOpenHashMap<K>`	`clone()` Returns a deep copy of this map.
`boolean`	`containsKey(Object k)` Checks whether the given value is contained in `AbstractReference2ShortMap.keySet()`.
`boolean`	`containsValue(short v)` Checks whether the given value is contained in `AbstractReference2ShortMap.values()`.
`short`	`getShort(Object k)` Returns the value to which the given key is mapped.
`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.
`boolean`	`isEmpty()`
`ReferenceSet<K>`	`keySet()` Returns a type-specific-set view of the keys of this map.
`short`	`put(K k, short v)` Adds a pair to the map.
`Short`	`put(K ok, Short ov)` Delegates to the corresponding type-specific method, taking care of returning `null` on a missing key.
`Reference2ShortMap.FastEntrySet<K>`	`reference2ShortEntrySet()` Returns a type-specific set view of the mappings contained in this map.
`boolean`	`rehash()` Deprecated. A no-op.
`protected void`	`rehash(int newN)` Resizes the map.
`Short`	`remove(Object ok)` Delegates to the corresponding type-specific method, taking care of returning `null` on a missing key.
`short`	`removeShort(Object k)` Removes the mapping with the given key.
`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.
`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.
`ShortCollection`	`values()` Returns a type-specific-set view of the values of this map.

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2ShortMap
containsValue, entrySet, equals, putAll, toString

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2ShortFunction
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.objects.Reference2ShortFunction
defaultReturnValue, defaultReturnValue

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

Methods inherited from interface java.util.Map
get

- Field Detail
  - serialVersionUID
```
public static final long serialVersionUID
```
    See Also:
    Constant Field Values
  - key
```
protected transient K[] key
```
    The array of keys.
  - value
```
protected transient short[] 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 Reference2ShortMap.FastEntrySet<K> entries
```
    Cached set of entries.
  - keys
```
protected transient volatile ReferenceSet<K> keys
```
    Cached set of keys.
  - values
```
protected transient volatile ShortCollection values
```
    Cached collection of values.
- Constructor Detail
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap(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.
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap(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.
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap()
```
    Creates a new hash map with initial expected Hash.DEFAULT_INITIAL_SIZE entries and Hash.DEFAULT_LOAD_FACTOR as load factor.
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap(Map<? extends K,? extends Short> 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.
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap(Map<? extends K,? extends Short> 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.
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap(Reference2ShortMap<K> 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.
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap(Reference2ShortMap<K> 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.
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap(K[] k,
                          short[] 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.
  - Reference2ShortOpenHashMap
```
public Reference2ShortOpenHashMap(K[] k,
                          short[] 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 short put(K k,
        short v)
```
    Description copied from interface: Reference2ShortFunction
    
    Adds a pair to the map.
    
    Specified by:
    
    put in interface Reference2ShortFunction<K>
    
    Overrides:
    
    put in class AbstractReference2ShortFunction<K>
    
    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 Short put(K ok,
        Short ov)
```
    Description copied from class: AbstractReference2ShortFunction
    
    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<K,Short>
    
    Specified by:
    
    put in interface Map<K,Short>
    
    Overrides:
    
    put in class AbstractReference2ShortFunction<K>
    
    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 short add(K k,
        short 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.
  - removeShort
```
public short removeShort(Object k)
```
    Description copied from interface: Reference2ShortFunction
    
    Removes the mapping with the given key.
    
    Specified by:
    
    removeShort in interface Reference2ShortFunction<K>
    
    Overrides:
    
    removeShort in class AbstractReference2ShortFunction<K>
    
    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 Short remove(Object ok)
```
    Description copied from class: AbstractReference2ShortFunction
    
    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<K,Short>
    
    Specified by:
    
    remove in interface Map<K,Short>
    
    Overrides:
    
    remove in class AbstractReference2ShortFunction<K>
    
    Returns:
    the old value, or null if no value was present for the given key.
    See Also:
    Map.remove(Object)
  - getShort
```
public short getShort(Object k)
```
    Description copied from interface: Reference2ShortFunction
    
    Returns the value to which the given key is mapped.
    
    Specified by:
    
    getShort in interface Reference2ShortFunction<K>
    
    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(Object k)
```
    Description copied from class: AbstractReference2ShortMap
    
    Checks whether the given value is contained in AbstractReference2ShortMap.keySet().
    
    Specified by:
    
    containsKey in interface Function<K,Short>
    
    Specified by:
    
    containsKey in interface Map<K,Short>
    
    Overrides:
    
    containsKey in class AbstractReference2ShortMap<K>
    
    Parameters:
    k - the key.
    
    Returns:
    true if this function associates a value to key.
    See Also:
    Map.containsKey(Object)
  - containsValue
```
public boolean containsValue(short v)
```
    Description copied from class: AbstractReference2ShortMap
    
    Checks whether the given value is contained in AbstractReference2ShortMap.values().
    
    Specified by:
    
    containsValue in interface Reference2ShortMap<K>
    
    Overrides:
    
    containsValue in class AbstractReference2ShortMap<K>
    
    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<K,Short>
    
    Specified by:
    
    clear in interface Map<K,Short>
    
    Overrides:
    
    clear in class AbstractReference2ShortFunction<K>
    
    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<K,Short>
    
    Specified by:
    
    size in interface Map<K,Short>
    
    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<K,Short>
    
    Overrides:
    
    isEmpty in class AbstractReference2ShortMap<K>
  - 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)
  - reference2ShortEntrySet
```
public Reference2ShortMap.FastEntrySet<K> reference2ShortEntrySet()
```
    Description copied from interface: Reference2ShortMap
    
    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 Reference2ShortMap.entrySet() so that it returns an ObjectSet of objects of type Map.Entry (the latter makes it possible to access keys and values with type-specific methods).
    
    Specified by:
    
    reference2ShortEntrySet in interface Reference2ShortMap<K>
    
    Returns:
    a type-specific set view of the mappings contained in this map.
    See Also:
    Reference2ShortMap.entrySet()
  - keySet
```
public ReferenceSet<K> keySet()
```
    Description copied from class: AbstractReference2ShortMap
    
    Returns a type-specific-set view of the keys of this map.
    The view is backed by the set returned by AbstractReference2ShortMap.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 Reference2ShortMap<K>
    
    Specified by:
    
    keySet in interface Map<K,Short>
    
    Overrides:
    
    keySet in class AbstractReference2ShortMap<K>
    
    Returns:
    a set view of the keys of this map; it may be safely cast to a type-specific interface.
    See Also:
    Map.keySet()
  - values
```
public ShortCollection values()
```
    Description copied from class: AbstractReference2ShortMap
    
    Returns a type-specific-set view of the values of this map.
    The view is backed by the set returned by AbstractReference2ShortMap.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 Reference2ShortMap<K>
    
    Specified by:
    
    values in interface Map<K,Short>
    
    Overrides:
    
    values in class AbstractReference2ShortMap<K>
    
    Returns:
    a set view of the values of this map; it may be safely cast to a type-specific interface.
    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 Reference2ShortOpenHashMap<K> 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<K,Short>
    
    Overrides:
    
    hashCode in class AbstractReference2ShortMap<K>
    
    Returns:
    a hash code for this map.

Class Reference2ShortOpenHashMap<K>

Nested Class Summary

Nested classes/interfaces inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2ShortMap

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

Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.objects.Reference2ShortMap

Field Summary

Fields inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2ShortFunction

Fields inherited from interface it.unimi.dsi.fastutil.Hash

Constructor Summary

Method Summary

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2ShortMap

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2ShortFunction

Methods inherited from class java.lang.Object

Methods inherited from interface it.unimi.dsi.fastutil.objects.Reference2ShortFunction

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

Methods inherited from interface java.util.Map

Field Detail

serialVersionUID

key

value

used

f

n

maxFill

mask

size

entries

keys

values

Constructor Detail

Reference2ShortOpenHashMap

Reference2ShortOpenHashMap

Reference2ShortOpenHashMap

Reference2ShortOpenHashMap

Reference2ShortOpenHashMap

Reference2ShortOpenHashMap

Reference2ShortOpenHashMap

Reference2ShortOpenHashMap

Reference2ShortOpenHashMap

Method Detail

put

put

add

shiftKeys

removeShort

remove

getShort

containsKey

containsValue

clear

size

isEmpty

growthFactor

growthFactor

reference2ShortEntrySet

keySet

values

rehash

trim

trim

rehash

clone

hashCode