Summary: Ctors | Methods | Inherited Methods | [Expand All]

Since: API Level 1

public class

EnumMap

extends AbstractMap<K, V>
implements Serializable Cloneable Map<K, V>

java.lang.Object
↳	java.util.AbstractMap<K, V>
	↳	java.util.EnumMap<K extends java.lang.Enum<K>, V>

Class Overview

An Map specialized for use with Enum types as keys.

Summary

Public Constructors
	EnumMap(Class<K> keyType) Constructs an empty `EnumMap` using the given key type.
	EnumMap(EnumMap<K, ? extends V> map) Constructs an `EnumMap` using the same key type as the given `EnumMap` and initially containing the same mappings.
	EnumMap(Map<K, ? extends V> map) Constructs an `EnumMap` initialized from the given map.

Public Methods
void	clear() Removes all elements from this `EnumMap`, leaving it empty.
EnumMap<K, V>	clone() Returns a shallow copy of this `EnumMap`.
boolean	containsKey(Object key) Returns whether this `EnumMap` contains the specified key.
boolean	containsValue(Object value) Returns whether this `EnumMap` contains the specified value.
Set<Entry<K, V>>	entrySet() Returns a `Set` containing all of the mappings in this `EnumMap`.
boolean	equals(Object object) Compares the argument to the receiver, and returns `true` if the specified `Object` is an `EnumMap` and both `EnumMap`s contain the same mappings.
V	get(Object key) Returns the value of the mapping with the specified key.
Set<K>	keySet() Returns a set of the keys contained in this `EnumMap`.
V	put(K key, V value) Maps the specified key to the specified value.
void	putAll(Map<? extends K, ? extends V> map) Copies every mapping in the specified `Map` to this `EnumMap`.
V	remove(Object key) Removes a mapping with the specified key from this `EnumMap`.
int	size() Returns the number of elements in this `EnumMap`.
Collection<V>	values() Returns a `Collection` of the values contained in this `EnumMap`.

[Expand]

Inherited Methods

From class java.util.AbstractMap

void	clear() Removes all elements from this `Map`, leaving it empty. This implementation calls `entrySet().clear()`.
Object	clone() Creates and returns a copy of this `Object`.
boolean	containsKey(Object key) Returns whether this `Map` contains the specified key. This implementation iterates its key set, looking for a key that `key` equals.
boolean	containsValue(Object value) Returns whether this `Map` contains the specified value. This implementation iterates its entry set, looking for an entry with a value that `value` equals.
abstract Set<Entry<K, V>>	entrySet() Returns a `Set` containing all of the mappings in this `Map`.
boolean	equals(Object object) Compares this instance with the specified object and indicates if they are equal. This implementation first checks the structure of `object`.
V	get(Object key) Returns the value of the mapping with the specified key. This implementation iterates its entry set, looking for an entry with a key that `key` equals.
int	hashCode() Returns an integer hash code for this object. This implementation iterates its entry set, summing the hashcodes of its entries.
boolean	isEmpty() Returns whether this map is empty. This implementation compares `size()` to 0.
Set<K>	keySet() Returns a set of the keys contained in this `Map`. This implementation returns a view that calls through this to map.
V	put(K key, V value) Maps the specified key to the specified value. This base implementation throws `UnsupportedOperationException`.
void	putAll(Map<? extends K, ? extends V> map) Copies every mapping in the specified `Map` to this `Map`. This implementation iterates through `map`'s entry set, calling `put()` for each.
V	remove(Object key) Removes a mapping with the specified key from this `Map`. This implementation iterates its entry set, removing the entry with a key that `key` equals.
int	size() Returns the number of mappings in this `Map`. This implementation returns its entry set's size.
String	toString() Returns a string containing a concise, human-readable description of this object. This implementation composes a string by iterating its entry set.
Collection<V>	values() Returns a `Collection` of the values contained in this `Map`. This implementation returns a view that calls through this to map.

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Called before the object's memory is reclaimed by the VM.
final Class<?>	getClass() Returns the unique instance of `Class` that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait(long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.

From interface java.util.Map

abstract void	clear() Removes all elements from this `Map`, leaving it empty.
abstract boolean	containsKey(Object key) Returns whether this `Map` contains the specified key.
abstract boolean	containsValue(Object value) Returns whether this `Map` contains the specified value.
abstract Set<Entry<K, V>>	entrySet() Returns a `Set` containing all of the mappings in this `Map`.
abstract boolean	equals(Object object) Compares the argument to the receiver, and returns `true` if the specified object is a `Map` and both `Map`s contain the same mappings.
abstract V	get(Object key) Returns the value of the mapping with the specified key.
abstract int	hashCode() Returns an integer hash code for the receiver.
abstract boolean	isEmpty() Returns whether this map is empty.
abstract Set<K>	keySet() Returns a set of the keys contained in this `Map`.
abstract V	put(K key, V value) Maps the specified key to the specified value.
abstract void	putAll(Map<? extends K, ? extends V> map) Copies every mapping in the specified `Map` to this `Map`.
abstract V	remove(Object key) Removes a mapping with the specified key from this `Map`.
abstract int	size() Returns the number of mappings in this `Map`.
abstract Collection<V>	values() Returns a `Collection` of the values contained in this `Map`.

Public Constructors

public EnumMap (Class<K> keyType)

Since: API Level 1

Constructs an empty EnumMap using the given key type.

Parameters

keyType	the class object giving the type of the keys used by this `EnumMap`.

Throws

NullPointerException	if `keyType` is `null`.

public EnumMap (EnumMap<K, ? extends V> map)

Since: API Level 1

Constructs an EnumMap using the same key type as the given EnumMap and initially containing the same mappings.

Parameters

map	the `EnumMap` from which this `EnumMap` is initialized.

Throws

NullPointerException	if `map` is `null`.

public EnumMap (Map<K, ? extends V> map)

Since: API Level 1

Constructs an EnumMap initialized from the given map. If the given map is an EnumMap instance, this constructor behaves in the exactly the same way as EnumMap(EnumMap)}. Otherwise, the given map should contain at least one mapping.

Parameters

map	the map from which this `EnumMap` is initialized.

Throws

IllegalArgumentException	if `map` is not an `EnumMap` instance and does not contain any mappings.
NullPointerException	if `map` is `null`.

Public Methods

public void clear ()

Since: API Level 1

Removes all elements from this EnumMap, leaving it empty.

public EnumMap<K, V> clone ()

Since: API Level 1

Returns a shallow copy of this EnumMap.

Returns

a shallow copy of this EnumMap.

public boolean containsKey (Object key)

Since: API Level 1

Returns whether this EnumMap contains the specified key.

Parameters

key	the key to search for.

Returns

true if this EnumMap contains the specified key, false otherwise.

public boolean containsValue (Object value)

Since: API Level 1

Returns whether this EnumMap contains the specified value.

Parameters

value	the value to search for.

Returns

true if this EnumMap contains the specified value, false otherwise.

public Set<Entry<K, V>> entrySet ()

Since: API Level 1

Returns a Set containing all of the mappings in this EnumMap. Each mapping is an instance of Map.Entry. As the Set is backed by this EnumMap, changes in one will be reflected in the other.

The order of the entries in the set will be the order that the enum keys were declared in.

Returns

a Set of the mappings.

public boolean equals (Object object)

Since: API Level 1

Compares the argument to the receiver, and returns true if the specified Object is an EnumMap and both EnumMaps contain the same mappings.

Parameters

object	the `Object` to compare with this `EnumMap`.

Returns

boolean true if object is the same as this EnumMap, false otherwise.

public V get (Object key)

Since: API Level 1

Returns the value of the mapping with the specified key.

Parameters

key	the key.

Returns

the value of the mapping with the specified key, or null if no mapping for the specified key is found.

public Set<K> keySet ()

Since: API Level 1

Returns a set of the keys contained in this EnumMap. The Set is backed by this EnumMap so changes to one are reflected in the other. The Set does not support adding.

The order of the set will be the order that the enum keys were declared in.

Returns

a Set of the keys.

public V put (K key, V value)

Since: API Level 1

Maps the specified key to the specified value.

Parameters

key	the key.
value	the value.

Returns

the value of any previous mapping with the specified key or null if there was no mapping.

Throws

UnsupportedOperationException	if adding to this map is not supported.
ClassCastException	if the class of the key or value is inappropriate for this map.
IllegalArgumentException	if the key or value cannot be added to this map.
NullPointerException	if the key or value is `null` and this `EnumMap` does not support `null` keys or values.

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

Since: API Level 1

Copies every mapping in the specified Map to this EnumMap.

Parameters

map	the `Map` to copy mappings from.

Throws

UnsupportedOperationException	if adding to this `EnumMap` is not supported.
ClassCastException	if the class of a key or value is inappropriate for this `EnumMap`.
IllegalArgumentException	if a key or value cannot be added to this map.
NullPointerException	if a key or value is `null` and this `EnumMap` does not support `null` keys or values.

public V remove (Object key)

Since: API Level 1

Removes a mapping with the specified key from this EnumMap.

Parameters

key	the key of the mapping to remove.

Returns

the value of the removed mapping or null if no mapping for the specified key was found.

Throws

UnsupportedOperationException	if removing from this `EnumMap` is not supported.

public int size ()

Since: API Level 1

Returns the number of elements in this EnumMap.

Returns

the number of elements in this EnumMap.

public Collection<V> values ()

Since: API Level 1

Returns a Collection of the values contained in this EnumMap. The returned Collection complies with the general rule specified in values(). The Collection's Iterator will return the values in the their corresponding keys' natural order (the Enum constants are declared in this order).

The order of the values in the collection will be the order that their corresponding enum keys were declared in.

Returns

a collection of the values contained in this EnumMap.

Interfaces

Classes

Enums

Exceptions

Errors

EnumMap

Class Overview

Summary

Public Constructors

public EnumMap (Class<K> keyType)

Parameters

Throws

public EnumMap (EnumMap<K, ? extends V> map)

Parameters

Throws

public EnumMap (Map<K, ? extends V> map)

Parameters

Throws

Public Methods

public void clear ()

See Also

public EnumMap<K, V> clone ()

Returns

public boolean containsKey (Object key)

Parameters

Returns

public boolean containsValue (Object value)

Parameters

Returns

public Set<Entry<K, V>> entrySet ()

Returns

public boolean equals (Object object)

Parameters

Returns

See Also

public V get (Object key)

Parameters

Returns

public Set<K> keySet ()

Returns

public V put (K key, V value)

Parameters

Returns

Throws

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

Parameters

Throws

public V remove (Object key)

Parameters

Returns

Throws

public int size ()

Returns

public Collection<V> values ()

Returns