org.cojen.util
Class IntHashMap<V>

java.lang.Object
  java.util.AbstractMap<Integer,V>
      org.cojen.util.IntHashMap<V>

All Implemented Interfaces:

Serializable, Cloneable, Map<Integer,V>

public class IntHashMap<V>
extends AbstractMap<Integer,V>
implements Map<Integer,V>, Cloneable, Serializable

A Map that accepts int or Integer keys only. This class is not thread-safe.

Author:

Brian S O'Neill

See Also:

Serialized Form

Constructor Summary

IntHashMap()
Constructs a new, empty map with a default capacity and load factor, which is 0.75.

IntHashMap(int initialCapacity)
Constructs a new, empty map with the specified initial capacity and default load factor, which is 0.75.

IntHashMap(int initialCapacity, float loadFactor)
Constructs a new, empty map with the specified initial capacity and the specified load factor.

IntHashMap(Map<? extends Integer,? extends V> t)
Constructs a new map with the same mappings as the given map.

Method Summary

void	clear() Removes all mappings from this map.
Object	clone() Returns a shallow copy of this IntHashMap instance: the keys and values themselves are not cloned.
boolean	containsKey(int key) Returns true if this map contains a mapping for the specified key.
boolean	containsKey(Integer key) Returns true if this map contains a mapping for the specified key.
boolean	containsValue(Object value) Returns true if this map maps one or more keys to the specified value.
Set<Map.Entry<Integer,V>>	entrySet() Returns a collection view of the mappings contained in this map.
V	get(int key) Returns the value to which this map maps the specified key.
V	get(Integer key) Returns the value to which this map maps the specified key.
boolean	isEmpty() Returns true if this map contains no key-value mappings.
Set<Integer>	keySet() Returns a set view of the keys contained in this map.
V	put(Integer key, V value) Associates the specified value with the specified key in this map.
V	put(int key, V value) Associates the specified value with the specified key in this map.
V	remove(int key) Removes the mapping for this key from this map if present.
V	remove(Integer key) Removes the mapping for this key from this map if present.
int	size() Returns the number of key-value mappings in this map.
Collection<V>	values() Returns a collection view of the values contained in this map.

Methods inherited from class java.util.AbstractMap

containsKey, equals, get, hashCode, putAll, remove, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

containsKey, equals, get, hashCode, putAll, remove

Constructor Detail

IntHashMap

public IntHashMap(int initialCapacity,
                  float loadFactor)

Constructs a new, empty map with the specified initial capacity and the specified load factor.

Parameters:

initialCapacity - the initial capacity of the IntHashMap.

loadFactor - the load factor of the IntHashMap

Throws:

IllegalArgumentException - if the initial capacity is less than zero, or if the load factor is nonpositive.

IntHashMap

public IntHashMap(int initialCapacity)

Constructs a new, empty map with the specified initial capacity and default load factor, which is 0.75.

Parameters:

initialCapacity - the initial capacity of the IntHashMap.

Throws:

IllegalArgumentException - if the initial capacity is less than zero.

IntHashMap

public IntHashMap()

Constructs a new, empty map with a default capacity and load factor, which is 0.75.

IntHashMap

public IntHashMap(Map<? extends Integer,? extends V> t)

Constructs a new map with the same mappings as the given map. The map is created with a capacity of twice the number of mappings in the given map or 11 (whichever is greater), and a default load factor, which is 0.75.

Method Detail

size

public int size()

Returns the number of key-value mappings in this map.

Specified by:

size in interface Map<Integer,V>

Overrides:

size in class AbstractMap<Integer,V>

Returns:

the number of key-value mappings in this map.

isEmpty

public boolean isEmpty()

Returns true if this map contains no key-value mappings.

Specified by:

isEmpty in interface Map<Integer,V>

Overrides:

isEmpty in class AbstractMap<Integer,V>

Returns:

true if this map contains no key-value mappings.

containsValue

public boolean containsValue(Object value)

Returns true if this map maps one or more keys to the specified value.

Specified by:

containsValue in interface Map<Integer,V>

Overrides:

containsValue in class AbstractMap<Integer,V>

Parameters:

value - value whose presence in this map is to be tested.

Returns:

true if this map maps one or more keys to the specified value.

containsKey

public boolean containsKey(Integer key)

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

Parameters:

key - key whose presence in this Map is to be tested.

Returns:

true if this map contains a mapping for the specified key.

containsKey

public boolean containsKey(int key)

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

Parameters:

key - key whose presence in this Map is to be tested.

Returns:

true if this map contains a mapping for the specified key.

get

public V get(Integer key)

Returns the value to which this map maps the specified key. Returns null if the map contains no mapping for this key. A return value of null does not necessarily indicate that the map contains no mapping for the key; it's also possible that the map explicitly maps the key to null. The containsKey operation may be used to distinguish these two cases.

Parameters:

key - key whose associated value is to be returned.

Returns:

the value to which this map maps the specified key.

get

public V get(int key)

Returns the value to which this map maps the specified key. Returns null if the map contains no mapping for this key. A return value of null does not necessarily indicate that the map contains no mapping for the key; it's also possible that the map explicitly maps the key to null. The containsKey operation may be used to distinguish these two cases.

Parameters:

key - key whose associated value is to be returned.

Returns:

the value to which this map maps the specified key.

put

public V put(Integer key,
             V value)

Associates the specified value with the specified key in this map. If the map previously contained a mapping for this key, the old value is replaced.

Specified by:

put in interface Map<Integer,V>

Overrides:

put in class AbstractMap<Integer,V>

Parameters:

key - key with which the specified value is to be associated.

value - value to be associated with the specified key.

Returns:

previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the IntHashMap previously associated null with the specified key.

put

public V put(int key,
             V value)

Associates the specified value with the specified key in this map. If the map previously contained a mapping for this key, the old value is replaced.

Parameters:

key - key with which the specified value is to be associated.

value - value to be associated with the specified key.

Returns:

previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the IntHashMap previously associated null with the specified key.

remove

public V remove(Integer key)

Removes the mapping for this key from this map if present.

Parameters:

key - key whose mapping is to be removed from the map.

Returns:

previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key.

remove

public V remove(int key)

Removes the mapping for this key from this map if present.

Parameters:

key - key whose mapping is to be removed from the map.

Returns:

previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key.

clear

public void clear()

Removes all mappings from this map.

Specified by:

clear in interface Map<Integer,V>

Overrides:

clear in class AbstractMap<Integer,V>

clone

public Object clone()

Returns a shallow copy of this IntHashMap instance: the keys and values themselves are not cloned.

Overrides:

clone in class AbstractMap<Integer,V>

Returns:

a shallow copy of this map.

keySet

public Set<Integer> keySet()

Returns a set view of the keys contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. The set supports element removal, which removes the corresponding mapping from this map, via the Iterator.remove, Set.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

Specified by:

keySet in interface Map<Integer,V>

Overrides:

keySet in class AbstractMap<Integer,V>

Returns:

a set view of the keys contained in this map.

values

public Collection<V> values()

Returns a collection view of the values contained in this map. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. The collection supports element removal, which removes the corresponding mapping from this map, via the Iterator.remove, Collection.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

Specified by:

values in interface Map<Integer,V>

Overrides:

values in class AbstractMap<Integer,V>

Returns:

a collection view of the values contained in this map.

entrySet

public Set<Map.Entry<Integer,V>> entrySet()

Returns a collection view of the mappings contained in this map. Each element in the returned collection is a Map.Entry. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. The collection supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Collection.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

Specified by:

entrySet in interface Map<Integer,V>

Specified by:

entrySet in class AbstractMap<Integer,V>

Returns:

a collection view of the mappings contained in this map.