it.unimi.dsi.fastutil.objects
Class Reference2LongArrayMap<K>

java.lang.Object
  extended by it.unimi.dsi.fastutil.objects.AbstractReference2LongFunction<K>
      extended by it.unimi.dsi.fastutil.objects.AbstractReference2LongMap<K>
          extended by it.unimi.dsi.fastutil.objects.Reference2LongArrayMap<K>
All Implemented Interfaces:
Function<K,java.lang.Long>, Reference2LongFunction<K>, Reference2LongMap<K>, java.io.Serializable, java.lang.Cloneable, java.util.Map<K,java.lang.Long>

public class Reference2LongArrayMap<K>
extends AbstractReference2LongMap<K>
implements java.io.Serializable, java.lang.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.objects.AbstractReference2LongMap
AbstractReference2LongMap.BasicEntry<K>
 
Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.objects.Reference2LongMap
Reference2LongMap.Entry<K>, Reference2LongMap.FastEntrySet<K>
 
Constructor Summary
Reference2LongArrayMap()
          Creates a new empty array map.
Reference2LongArrayMap(int capacity)
          Creates a new empty array map of given capacity.
Reference2LongArrayMap(java.util.Map<? extends K,? extends java.lang.Long> m)
          Creates a new empty array map copying the entries of a given map.
Reference2LongArrayMap(java.lang.Object[] key, long[] value)
          Creates a new empty array map with given key and value backing arrays.
Reference2LongArrayMap(java.lang.Object[] key, long[] value, int size)
          Creates a new array map with given key and value backing arrays, using the given number of elements.
Reference2LongArrayMap(Reference2LongMap<K> m)
          Creates a new empty array map copying the entries of a given map.
 
Method Summary
 void clear()
          Removes all associations from this function (optional operation).
 Reference2LongArrayMap<K> clone()
          Returns a deep copy of this map.
 boolean containsKey(java.lang.Object k)
          Checks whether the given value is contained in AbstractReference2LongMap.keySet().
 boolean containsValue(long v)
          Checks whether the given value is contained in AbstractReference2LongMap.values().
 long getLong(java.lang.Object k)
          Returns the value to which the given key is mapped.
 boolean isEmpty()
           
 ReferenceSet<K> keySet()
          Returns a type-specific-set view of the keys of this map.
 long put(K k, long v)
          Adds a pair to the map.
 Reference2LongMap.FastEntrySet<K> reference2LongEntrySet()
          Returns a type-specific set view of the mappings contained in this map.
 long removeLong(java.lang.Object 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.
 LongCollection values()
          Returns a type-specific-set view of the values of this map.
 
Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2LongMap
containsValue, entrySet, equals, hashCode, putAll, toString
 
Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2LongFunction
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.objects.Reference2LongFunction
defaultReturnValue, defaultReturnValue
 
Methods inherited from interface it.unimi.dsi.fastutil.Function
get, put, remove
 
Methods inherited from interface java.util.Map
get, put, remove
 

Constructor Detail

Reference2LongArrayMap

public Reference2LongArrayMap(java.lang.Object[] key,
                              long[] 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).

Reference2LongArrayMap

public Reference2LongArrayMap()
Creates a new empty array map.


Reference2LongArrayMap

public Reference2LongArrayMap(int capacity)
Creates a new empty array map of given capacity.

Parameters:
capacity - the initial capacity.

Reference2LongArrayMap

public Reference2LongArrayMap(Reference2LongMap<K> m)
Creates a new empty array map copying the entries of a given map.

Parameters:
m - a map.

Reference2LongArrayMap

public Reference2LongArrayMap(java.util.Map<? extends K,? extends java.lang.Long> m)
Creates a new empty array map copying the entries of a given map.

Parameters:
m - a map.

Reference2LongArrayMap

public Reference2LongArrayMap(java.lang.Object[] key,
                              long[] 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

reference2LongEntrySet

public Reference2LongMap.FastEntrySet<K> reference2LongEntrySet()
Description copied from interface: Reference2LongMap
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 Reference2LongMap.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:
reference2LongEntrySet in interface Reference2LongMap<K>
Returns:
a type-specific set view of the mappings contained in this map.
See Also:
Reference2LongMap.entrySet()

getLong

public long getLong(java.lang.Object k)
Description copied from interface: Reference2LongFunction
Returns the value to which the given key is mapped.

Specified by:
getLong in interface Reference2LongFunction<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)

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,java.lang.Long>
Specified by:
size in interface java.util.Map<K,java.lang.Long>
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<K,java.lang.Long>
Specified by:
clear in interface java.util.Map<K,java.lang.Long>
Overrides:
clear in class AbstractReference2LongFunction<K>
See Also:
Map.clear()

containsKey

public boolean containsKey(java.lang.Object k)
Description copied from class: AbstractReference2LongMap
Checks whether the given value is contained in AbstractReference2LongMap.keySet().

Specified by:
containsKey in interface Function<K,java.lang.Long>
Specified by:
containsKey in interface java.util.Map<K,java.lang.Long>
Overrides:
containsKey in class AbstractReference2LongMap<K>
Parameters:
k - the key.
Returns:
true if this function associates a value to key.
See Also:
Map.containsKey(Object)

containsValue

public boolean containsValue(long v)
Description copied from class: AbstractReference2LongMap
Checks whether the given value is contained in AbstractReference2LongMap.values().

Specified by:
containsValue in interface Reference2LongMap<K>
Overrides:
containsValue in class AbstractReference2LongMap<K>
See Also:
Map.containsValue(Object)

isEmpty

public boolean isEmpty()
Specified by:
isEmpty in interface java.util.Map<K,java.lang.Long>
Overrides:
isEmpty in class AbstractReference2LongMap<K>

put

public long put(K k,
                long v)
Description copied from interface: Reference2LongFunction
Adds a pair to the map.

Specified by:
put in interface Reference2LongFunction<K>
Overrides:
put in class AbstractReference2LongFunction<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)

removeLong

public long removeLong(java.lang.Object k)
Description copied from interface: Reference2LongFunction
Removes the mapping with the given key.

Specified by:
removeLong in interface Reference2LongFunction<K>
Overrides:
removeLong in class AbstractReference2LongFunction<K>
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 ReferenceSet<K> keySet()
Description copied from class: AbstractReference2LongMap
Returns a type-specific-set view of the keys of this map.

The view is backed by the set returned by AbstractReference2LongMap.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 Reference2LongMap<K>
Specified by:
keySet in interface java.util.Map<K,java.lang.Long>
Overrides:
keySet in class AbstractReference2LongMap<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 LongCollection values()
Description copied from class: AbstractReference2LongMap
Returns a type-specific-set view of the values of this map.

The view is backed by the set returned by AbstractReference2LongMap.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 Reference2LongMap<K>
Specified by:
values in interface java.util.Map<K,java.lang.Long>
Overrides:
values in class AbstractReference2LongMap<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()

clone

public Reference2LongArrayMap<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 java.lang.Object
Returns:
a deep copy of this map.