Android
java.util
public interface

java.util.Map<K, V>

java.util.Map<K, V>

Map has a set of keys, each key is mapped to a single value.

Nested Classes
Map.Entry<K, V> Map.Entry is a key/value mapping which is contained in a Map. 
Known Indirect Subclasses

Summary

Public Methods

          void  clear()
Removes all elements from this Map, leaving it empty.
          boolean  containsKey(Object key)
Searches this Map for the specified key.
          boolean  containsValue(Object value)
Searches this Map for the specified value.
          Set<Entry<K, V>>  entrySet()
Returns a Set whose elements comprise all of the mappings that are to be found in this Map.
          boolean  equals(Object object)
Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
          get(Object key)
Returns the value of the mapping with the specified key.
          int  hashCode()
Returns an integer hash code for the receiver.
          boolean  isEmpty()
Returns if this Map has no elements, a size of zero.
          Set<K>  keySet()
Returns a Set of the keys contained in this Map.
          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 Map.
          remove(Object key)
Removes a mapping with the specified key from this Map.
          int  size()
Returns the number of elements in this Map.
          Collection<V>  values()
Returns all of the current Map values in a Collection.

Details

Public Methods

public void clear()

Removes all elements from this Map, leaving it empty.

Throws

UnsupportedOperationException when removing from this Map is not supported

See Also

public boolean containsKey(Object key)

Searches this Map for the specified key.

Parameters

key the object to search for

Returns

  • true if key is a key of this Map, false otherwise

public boolean containsValue(Object value)

Searches this Map for the specified value.

Parameters

value the object to search for

Returns

  • true if value is a value of this Map, false otherwise

public Set<Entry<K, V>> entrySet()

Returns a Set whose elements comprise all of the mappings that are to be found in this Map. Information on each of the mappings is encapsulated in a separate Map.Entry instance. As the Set is backed by this Map, users should be aware that changes in one will be immediately visible in the other.

Returns

  • a Set of the mappings

public boolean equals(Object object)

Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.

Parameters

object Object the object to compare with this object.

Returns

  • boolean true if the object is the same as this object false if it is different from this object.

See Also

public V get(Object key)

Returns the value of the mapping with the specified key.

Parameters

key the key

Returns

  • the value of the mapping with the specified key

public int hashCode()

Returns an integer hash code for the receiver. Objects which are equal answer the same value for this method.

Returns

  • the receiver's hash

See Also

public boolean isEmpty()

Returns if this Map has no elements, a size of zero.

Returns

  • true if this Map has no elements, false otherwise

See Also

public Set<K> keySet()

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

Returns

  • a Set of the keys

public V put(K key, V value)

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 when adding to this Map is not supported
ClassCastException when the class of the key or value is inappropriate for this Map
IllegalArgumentException when the key or value cannot be added to this Map
NullPointerException when the key or value is null and this Map does not support null keys or values

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

Copies every mapping in the specified Map to this Map.

Parameters

map the Map to copy mappings from

Throws

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

public V remove(Object key)

Removes a mapping with the specified key from this Map.

Parameters

key the key of the mapping to remove

Returns

  • the value of the removed mapping or null if key is not a key in this Map

Throws

UnsupportedOperationException when removing from this Map is not supported

public int size()

Returns the number of elements in this Map.

Returns

  • the number of elements in this Map

public Collection<V> values()

Returns all of the current Map values in a Collection. As the returned Collection is backed by this Map, users should be aware that changes in one will be immediately visible in the other.

Returns

  • a Collection of the values
Copyright 2007 Google Inc. Build 0.9_r1-98467 - 14 Aug 2008 18:56