Package org.apache.commons.collections4.bidimap

This package contains implementations of the BidiMap, OrderedBidiMap and SortedBidiMap interfaces. A BidiMap is an extension to Map that allows keys and values to be looked up with equal ease. One example usage is a system communicating to a legacy datasource that must convert codes from the new format to the old format and vice versa.

The following implementations are provided in the package:

• DualHashBidiMap - uses two HashMaps to implement BidiMap
• DualLinkedHashBidiMap - uses two LinkedHashMaps to implement BidiMap
• DualTreeBidiMap - uses two TreeMaps to implement SortedBidiMap
• TreeBidiMap - red-black tree implementation of OrderedBidiMap

The following decorators are provided in the package:

• Unmodifiable - ensures the map cannot be altered

Class Summary

Class	Description
AbstractBidiMapDecorator<K,V>	Provides a base decorator that enables additional functionality to be added to a BidiMap via decoration.
AbstractDualBidiMap<K,V>	Abstract BidiMap implemented using two maps.
AbstractOrderedBidiMapDecorator<K,V>	Provides a base decorator that enables additional functionality to be added to an OrderedBidiMap via decoration.
AbstractSortedBidiMapDecorator<K,V>	Provides a base decorator that enables additional functionality to be added to a SortedBidiMap via decoration.
DualHashBidiMap<K,V>	Implementation of BidiMap that uses two HashMap instances.
DualLinkedHashBidiMap<K,V>	Implementation of BidiMap that uses two LinkedHashMap instances.
DualTreeBidiMap<K,V>	Implementation of BidiMap that uses two TreeMap instances.
TreeBidiMap<K extends java.lang.Comparable<K>,V extends java.lang.Comparable<V>>	Red-Black tree-based implementation of BidiMap where all objects added implement the Comparable interface.
UnmodifiableBidiMap<K,V>	Decorates another BidiMap to ensure it can't be altered.
UnmodifiableOrderedBidiMap<K,V>	Decorates another OrderedBidiMap to ensure it can't be altered.
UnmodifiableSortedBidiMap<K,V>	Decorates another SortedBidiMap to ensure it can't be altered.