org.apache.commons.collections4.multimap

Class AbstractListValuedMap<K,V>

java.lang.Object

org.apache.commons.collections4.multimap.AbstractMultiValuedMap<K,V>

org.apache.commons.collections4.multimap.AbstractListValuedMap<K,V>

Type Parameters:

K - the type of the keys in this map

V - the type of the values in this map

All Implemented Interfaces:

ListValuedMap<K,V>, MultiValuedMap<K,V>

Direct Known Subclasses:

ArrayListValuedHashMap

public abstract class AbstractListValuedMap<K,V>
extends AbstractMultiValuedMap<K,V>
implements ListValuedMap<K,V>

Abstract implementation of the ListValuedMap interface to simplify the creation of subclass implementations.

Subclasses specify a Map implementation to use as the internal storage and the List implementation to use as values.

Since:

4.1

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private class	AbstractListValuedMap.ValuesListIterator Values ListIterator
private class	AbstractListValuedMap.WrappedList Wrapped list to handle add and remove on the list returned by get(object)

Nested classes/interfaces inherited from class org.apache.commons.collections4.multimap.AbstractMultiValuedMap

AbstractMultiValuedMap.WrappedCollection

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractListValuedMap() Constructor needed for subclass serialisation.
protected	AbstractListValuedMap(java.util.Map<K,? extends java.util.List<V>> map) A constructor that wraps, not copies

Method Summary

Modifier and Type	Method and Description
protected abstract java.util.List<V>	createCollection() Creates a new value collection using the provided factory.
java.util.List<V>	get(K key) Gets the list of values associated with the specified key.
protected java.util.Map<K,java.util.List<V>>	getMap() Gets the map being wrapped.
java.util.List<V>	remove(java.lang.Object key) Removes all values associated with the specified key.
(package private) java.util.List<V>	wrappedCollection(K key)

Methods inherited from class org.apache.commons.collections4.multimap.AbstractMultiValuedMap

asMap, clear, containsKey, containsMapping, containsValue, doReadObject, doWriteObject, entries, equals, hashCode, isEmpty, keys, keySet, mapIterator, put, putAll, putAll, putAll, removeMapping, setMap, size, toString, values

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.commons.collections4.MultiValuedMap

asMap, clear, containsKey, containsMapping, containsValue, entries, isEmpty, keys, keySet, mapIterator, put, putAll, putAll, putAll, removeMapping, size, values

Constructor Detail

AbstractListValuedMap

protected AbstractListValuedMap()

Constructor needed for subclass serialisation.

AbstractListValuedMap

protected AbstractListValuedMap(java.util.Map<K,? extends java.util.List<V>> map)

A constructor that wraps, not copies

Parameters:

map - the map to wrap, must not be null

Throws:

java.lang.NullPointerException - if the map is null

Method Detail

getMap

protected java.util.Map<K,java.util.List<V>> getMap()

Description copied from class: AbstractMultiValuedMap

Gets the map being wrapped.

Overrides:

getMap in class AbstractMultiValuedMap<K,V>

Returns:

the wrapped map

createCollection

protected abstract java.util.List<V> createCollection()

Creates a new value collection using the provided factory.

Specified by:

createCollection in class AbstractMultiValuedMap<K,V>

Returns:

a new list

get

public java.util.List<V> get(K key)

Gets the list of values associated with the specified key. This would return an empty list in case the mapping is not present

Specified by:

get in interface ListValuedMap<K,V>

Specified by:

get in interface MultiValuedMap<K,V>

Overrides:

get in class AbstractMultiValuedMap<K,V>

Parameters:

key - the key to retrieve

Returns:

the List of values, will return an empty List for no mapping

wrappedCollection

java.util.List<V> wrappedCollection(K key)

Overrides:

wrappedCollection in class AbstractMultiValuedMap<K,V>

remove

public java.util.List<V> remove(java.lang.Object key)

Removes all values associated with the specified key.

A subsequent get(Object) would return an empty list.

Specified by:

remove in interface ListValuedMap<K,V>

Specified by:

remove in interface MultiValuedMap<K,V>

Overrides:

remove in class AbstractMultiValuedMap<K,V>

Parameters:

key - the key to remove values from

Returns:

the List of values removed, will return an empty, unmodifiable list for no mapping found.