it.unimi.dsi.fastutil.bytes
Class Byte2ReferenceArrayMap<V>

java.lang.Object
  extended by it.unimi.dsi.fastutil.bytes.AbstractByte2ReferenceFunction<V>
      extended by it.unimi.dsi.fastutil.bytes.AbstractByte2ReferenceMap<V>
          extended by it.unimi.dsi.fastutil.bytes.Byte2ReferenceArrayMap<V>
All Implemented Interfaces:
Byte2ReferenceFunction<V>, Byte2ReferenceMap<V>, Function<Byte,V>, Serializable, Cloneable, Map<Byte,V>

public class Byte2ReferenceArrayMap<V>
extends AbstractByte2ReferenceMap<V>
implements Serializable, Cloneable

A simple, brute-force implementation of a map based on two parallel backing arrays.

The main purpose of this implementation is that of wrapping cleanly the brute-force approach to the storage of a very small number of pairs: just put them into two parallel arrays and scan linearly to find an item.

See Also:
Serialized Form

Nested Class Summary
 
Nested classes/interfaces inherited from class it.unimi.dsi.fastutil.bytes.AbstractByte2ReferenceMap
AbstractByte2ReferenceMap.BasicEntry<V>
 
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.bytes.Byte2ReferenceMap
Byte2ReferenceMap.Entry<V>, Byte2ReferenceMap.FastEntrySet<V>
 
Constructor Summary
Byte2ReferenceArrayMap()
          Creates a new empty array map.
Byte2ReferenceArrayMap(byte[] key, Object[] value)
          Creates a new empty array map with given key and value backing arrays.
Byte2ReferenceArrayMap(byte[] key, Object[] value, int size)
          Creates a new array map with given key and value backing arrays, using the given number of elements.
Byte2ReferenceArrayMap(Byte2ReferenceMap<V> m)
          Creates a new empty array map copying the entries of a given map.
Byte2ReferenceArrayMap(int capacity)
          Creates a new empty array map of given capacity.
Byte2ReferenceArrayMap(Map<? extends Byte,? extends V> m)
          Creates a new empty array map copying the entries of a given map.
 
Method Summary
 Byte2ReferenceMap.FastEntrySet<V> byte2ReferenceEntrySet()
          Returns a type-specific set view of the mappings contained in this map.
 void clear()
          Removes all associations from this function (optional operation).
 Byte2ReferenceArrayMap<V> clone()
          Returns a deep copy of this map.
 boolean containsKey(byte k)
          Checks whether the given value is contained in AbstractByte2ReferenceMap.keySet().
 boolean containsValue(Object v)
          Checks whether the given value is contained in AbstractByte2ReferenceMap.values().
 V get(byte k)
          Returns the value to which the given key is mapped.
 boolean isEmpty()
           
 ByteSet keySet()
          Returns a type-specific-set view of the keys of this map.
 V put(byte k, V v)
          Adds a pair to the map.
 V remove(byte k)
          Removes the mapping with the given key.
 int size()
          Returns the intended number of keys in this function, or -1 if no such number exists.
 ReferenceCollection<V> values()
          Returns a type-specific-set view of the values of this map.
 
Methods inherited from class it.unimi.dsi.fastutil.bytes.AbstractByte2ReferenceMap
entrySet, equals, hashCode, putAll, toString
 
Methods inherited from class it.unimi.dsi.fastutil.bytes.AbstractByte2ReferenceFunction
containsKey, defaultReturnValue, defaultReturnValue, get, put, remove
 
Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface it.unimi.dsi.fastutil.bytes.Byte2ReferenceFunction
defaultReturnValue, defaultReturnValue
 
Methods inherited from interface it.unimi.dsi.fastutil.Function
containsKey, get, put, remove
 
Methods inherited from interface java.util.Map
containsKey, get, put, remove
 

Constructor Detail

Byte2ReferenceArrayMap

public Byte2ReferenceArrayMap(byte[] key,
                              Object[] value)
Creates a new empty array map with given key and value backing arrays. The resulting map will have as many entries as the given arrays.

It is responsibility of the caller that the elements of key are distinct.

Parameters:
key - the key array.
value - the value array (it must have the same length as key).

Byte2ReferenceArrayMap

public Byte2ReferenceArrayMap()
Creates a new empty array map.


Byte2ReferenceArrayMap

public Byte2ReferenceArrayMap(int capacity)
Creates a new empty array map of given capacity.

Parameters:
capacity - the initial capacity.

Byte2ReferenceArrayMap

public Byte2ReferenceArrayMap(Byte2ReferenceMap<V> m)
Creates a new empty array map copying the entries of a given map.

Parameters:
m - a map.

Byte2ReferenceArrayMap

public Byte2ReferenceArrayMap(Map<? extends Byte,? extends V> m)
Creates a new empty array map copying the entries of a given map.

Parameters:
m - a map.

Byte2ReferenceArrayMap

public Byte2ReferenceArrayMap(byte[] key,
                              Object[] value,
                              int size)
Creates a new array map with given key and value backing arrays, using the given number of elements.

It is responsibility of the caller that the first size elements of key are distinct.

Parameters:
key - the key array.
value - the value array (it must have the same length as key).
size - the number of valid elements in key and value.
Method Detail

byte2ReferenceEntrySet

public Byte2ReferenceMap.FastEntrySet<V> byte2ReferenceEntrySet()
Description copied from interface: Byte2ReferenceMap
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 Byte2ReferenceMap.entrySet() so that it returns an ObjectSet of objects of type Byte2ReferenceMap.Entry (the latter makes it possible to access keys and values with type-specific methods).

Specified by:
byte2ReferenceEntrySet in interface Byte2ReferenceMap<V>
Returns:
a type-specific set view of the mappings contained in this map.
See Also:
Byte2ReferenceMap.entrySet()

get

public V get(byte k)
Description copied from interface: Byte2ReferenceFunction
Returns the value to which the given key is mapped.

Specified by:
get in interface Byte2ReferenceFunction<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)

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

clear

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

Specified by:
clear in interface Function<Byte,V>
Specified by:
clear in interface Map<Byte,V>
Overrides:
clear in class AbstractByte2ReferenceFunction<V>
See Also:
Map.clear()

containsKey

public boolean containsKey(byte k)
Description copied from class: AbstractByte2ReferenceMap
Checks whether the given value is contained in AbstractByte2ReferenceMap.keySet().

Specified by:
containsKey in interface Byte2ReferenceFunction<V>
Overrides:
containsKey in class AbstractByte2ReferenceMap<V>
See Also:
Function.containsKey(Object)

containsValue

public boolean containsValue(Object v)
Description copied from class: AbstractByte2ReferenceMap
Checks whether the given value is contained in AbstractByte2ReferenceMap.values().

Specified by:
containsValue in interface Map<Byte,V>
Overrides:
containsValue in class AbstractByte2ReferenceMap<V>

isEmpty

public boolean isEmpty()
Specified by:
isEmpty in interface Map<Byte,V>
Overrides:
isEmpty in class AbstractByte2ReferenceMap<V>

put

public V put(byte k,
             V v)
Description copied from interface: Byte2ReferenceFunction
Adds a pair to the map.

Specified by:
put in interface Byte2ReferenceFunction<V>
Overrides:
put in class AbstractByte2ReferenceFunction<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)

remove

public V remove(byte k)
Description copied from interface: Byte2ReferenceFunction
Removes the mapping with the given key.

Specified by:
remove in interface Byte2ReferenceFunction<V>
Overrides:
remove in class AbstractByte2ReferenceFunction<V>
Returns:
the old value, or the default return value if no value was present for the given key.
See Also:
Function.remove(Object)

keySet

public ByteSet keySet()
Description copied from class: AbstractByte2ReferenceMap
Returns a type-specific-set view of the keys of this map.

The view is backed by the set returned by AbstractByte2ReferenceMap.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 Byte2ReferenceMap<V>
Specified by:
keySet in interface Map<Byte,V>
Overrides:
keySet in class AbstractByte2ReferenceMap<V>
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 ReferenceCollection<V> values()
Description copied from class: AbstractByte2ReferenceMap
Returns a type-specific-set view of the values of this map.

The view is backed by the set returned by AbstractByte2ReferenceMap.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 Byte2ReferenceMap<V>
Specified by:
values in interface Map<Byte,V>
Overrides:
values in class AbstractByte2ReferenceMap<V>
Returns:
a set view of the values of this map; it may be safely cast to a type-specific interface.
See Also:
Map.values()

clone

public Byte2ReferenceArrayMap<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.