Package it.unimi.dsi.fastutil.objects

Class AbstractObject2ObjectMap<K,V>

java.lang.Object

it.unimi.dsi.fastutil.objects.AbstractObject2ObjectFunction<K,V>

it.unimi.dsi.fastutil.objects.AbstractObject2ObjectMap<K,V>

All Implemented Interfaces:

Function<K,V>, Object2ObjectFunction<K,V>, Object2ObjectMap<K,V>, Serializable, Function<K,V>, Map<K,V>

Direct Known Subclasses:

AbstractObject2ObjectSortedMap, Object2ObjectArrayMap, Object2ObjectOpenCustomHashMap, Object2ObjectOpenHashMap

public abstract class AbstractObject2ObjectMap<K,V>
extends AbstractObject2ObjectFunction<K,V>
implements Object2ObjectMap<K,V>, Serializable

An abstract class providing basic methods for maps implementing a type-specific interface.

Optional operations just throw an UnsupportedOperationException. Generic versions of accessors delegate to the corresponding type-specific counterparts following the interface rules (they take care of returning null on a missing key).

As a further help, this class provides a BasicEntry inner class that implements a type-specific version of Map.Entry; it is particularly useful for those classes that do not implement their own entries (e.g., most immutable maps).

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AbstractObject2ObjectMap.BasicEntry<K,V>	This class provides a basic but complete type-specific entry class for all those maps implementations that do not have entries on their own (e.g., most immutable maps).
static class	AbstractObject2ObjectMap.BasicEntrySet<K,V>	This class provides a basic implementation for an Entry set which forwards some queries to the map.

Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.objects.Object2ObjectMap

Object2ObjectMap.Entry<K,V>, Object2ObjectMap.FastEntrySet<K,V>

Method Summary

Modifier and Type	Method	Description
boolean	containsKey(Object k)	Returns true if this function contains a mapping for the specified key.
boolean	containsValue(Object v)
boolean	equals(Object o)
int	hashCode()	Returns a hash code for this map.
boolean	isEmpty()
ObjectSet<K>	keySet()	Returns a type-specific-set view of the keys of this map.
void	putAll(Map<? extends K,? extends V> m)
String	toString()
ObjectCollection<V>	values()	Returns a type-specific-set view of the values of this map.

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractObject2ObjectFunction

defaultReturnValue, defaultReturnValue

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

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

apply

Methods inherited from interface java.util.function.Function

andThen, compose

Methods inherited from interface java.util.Map

computeIfAbsent, get, replaceAll

Methods inherited from interface it.unimi.dsi.fastutil.objects.Object2ObjectFunction

andThenByte, andThenChar, andThenDouble, andThenFloat, andThenInt, andThenLong, andThenObject, andThenReference, andThenShort, composeByte, composeChar, composeDouble, composeFloat, composeInt, composeLong, composeObject, composeReference, composeShort, get

Methods inherited from interface it.unimi.dsi.fastutil.objects.Object2ObjectMap

clear, compute, computeIfAbsent, computeIfPresent, computeObjectIfAbsentPartial, defaultReturnValue, defaultReturnValue, entrySet, forEach, getOrDefault, merge, object2ObjectEntrySet, put, putIfAbsent, remove, remove, replace, replace, size

Method Details

containsKey

public boolean containsKey(Object k)

Returns true if this function contains a mapping for the specified key.

Specified by:

containsKey in interface Function<K,V>

Specified by:

containsKey in interface Map<K,V>

Specified by:

containsKey in interface Object2ObjectMap<K,V>

Parameters:

k - the key.

Returns:

true if this function associates a value to key.

See Also:

• Map.containsKey(Object)

Implementation Specification:

This implementation does a linear search over the entry set, finding an entry that has the key specified.

If you override keySet(), you should probably override this method too to take advantage of the (presumably) faster key membership test your keySet() provides.

If you override this method but not keySet(), then the returned key set will take advantage of this method.

containsValue

public boolean containsValue(Object v)

Specified by:

containsValue in interface Map<K,V>

Implementation Specification:

This implementation does a linear search over the entry set, finding an entry that has the value specified.

If you override values(), you should probably override this method too to take advantage of the (presumably) faster value membership test your values() provides.

If you override this method but not values(), then the returned values collection will take advantage of this method.

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<K,V>

keySet

public ObjectSet<K> keySet()

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

The view is backed by the set returned by Map.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 Map<K,V>

Specified by:

keySet in interface Object2ObjectMap<K,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 ObjectCollection<V> values()

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

The view is backed by the set returned by Map.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 Map<K,V>

Specified by:

values in interface Object2ObjectMap<K,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()

putAll

public void putAll(Map<? extends K,? extends V> m)

Specified by:

putAll in interface Map<K,V>

hashCode

public int hashCode()

Returns a hash code for this map. The hash code of a map is computed by summing the hash codes of its entries.

Specified by:

hashCode in interface Map<K,V>

Overrides:

hashCode in class Object

Returns:

a hash code for this map.

equals

public boolean equals(Object o)

Specified by:

equals in interface Map<K,V>

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object