java.lang.Object
- org.apache.commons.collections.bidimap.AbstractDualBidiMap

All Implemented Interfaces:

Map, BidiMap, IterableMap

Direct Known Subclasses:

DualHashBidiMap, DualTreeBidiMap
```
public abstract class AbstractDualBidiMap
extends Object
implements BidiMap
```
Abstract BidiMap implemented using two maps.
An implementation can be written simply by implementing the createMap method.

Since:

Commons Collections 3.0

Version:

$Id: AbstractDualBidiMap.java 646777 2008-04-10 12:33:15Z niallp $

Author:

Matthew Hawthorne, Stephen Colebourne

See Also:

DualHashBidiMap, DualTreeBidiMap

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`protected static class`	`AbstractDualBidiMap.BidiMapIterator`	Inner class MapIterator.
`protected static class`	`AbstractDualBidiMap.EntrySet`	Inner class EntrySet.
`protected static class`	`AbstractDualBidiMap.EntrySetIterator`	Inner class EntrySetIterator.
`protected static class`	`AbstractDualBidiMap.KeySet`	Inner class KeySet.
`protected static class`	`AbstractDualBidiMap.KeySetIterator`	Inner class KeySetIterator.
`protected static class`	`AbstractDualBidiMap.MapEntry`	Inner class MapEntry.
`protected static class`	`AbstractDualBidiMap.Values`	Inner class Values.
`protected static class`	`AbstractDualBidiMap.ValuesIterator`	Inner class ValuesIterator.
`protected static class`	`AbstractDualBidiMap.View`	Inner class View.

Nested classes/interfaces inherited from interface java.util.Map
Map.Entry<K extends Object,V extends Object>

Field Summary

Fields
Modifier and Type	Field	Description
`protected Set`	`entrySet`	View of the entries.
`protected BidiMap`	`inverseBidiMap`	Inverse view of this map.
`protected Set`	`keySet`	View of the keys.
`protected Map[]`	`maps`	Delegate map array.
`protected Collection`	`values`	View of the values.

Constructor Summary

Constructors
Modifier	Constructor	Description
`protected`	`AbstractDualBidiMap()`	Creates an empty map, initialised by `createMap`.
`protected`	`AbstractDualBidiMap(Map normalMap, Map reverseMap)`	Creates an empty map using the two maps specified as storage.
`protected`	`AbstractDualBidiMap(Map normalMap, Map reverseMap, BidiMap inverseBidiMap)`	Constructs a map that decorates the specified maps, used by the subclass `createBidiMap` implementation.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`void`	`clear()`
`boolean`	`containsKey(Object key)`
`boolean`	`containsValue(Object value)`
`protected abstract BidiMap`	`createBidiMap(Map normalMap, Map reverseMap, BidiMap inverseMap)`	Creates a new instance of the subclass.
`protected Iterator`	`createEntrySetIterator(Iterator iterator)`	Creates an entry set iterator.
`protected Iterator`	`createKeySetIterator(Iterator iterator)`	Creates a key set iterator.
`protected Map`	`createMap()`	Deprecated. For constructors, use the new two map constructor.
`protected Iterator`	`createValuesIterator(Iterator iterator)`	Creates a values iterator.
`Set`	`entrySet()`	Gets an entrySet view of the map.
`boolean`	`equals(Object obj)`
`Object`	`get(Object key)`
`Object`	`getKey(Object value)`	Gets the key that is currently mapped to the specified value.
`int`	`hashCode()`
`BidiMap`	`inverseBidiMap()`	Gets a view of this map where the keys and values are reversed.
`boolean`	`isEmpty()`
`Set`	`keySet()`	Gets a keySet view of the map.
`MapIterator`	`mapIterator()`	Obtains a `MapIterator` over the map.
`Object`	`put(Object key, Object value)`	Puts the key-value pair into the map, replacing any previous pair.
`void`	`putAll(Map map)`
`Object`	`remove(Object key)`
`Object`	`removeValue(Object value)`	Removes the key-value pair that is currently mapped to the specified value (optional operation).
`int`	`size()`
`String`	`toString()`
`Collection`	`values()`	Gets a values view of the map.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map
compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll

- Field Detail
  - maps
```
protected final transient Map[] maps
```
    Delegate map array. The first map contains standard entries, and the second contains inverses.
  - inverseBidiMap
```
protected transient BidiMap inverseBidiMap
```
    Inverse view of this map.
  - keySet
```
protected transient Set keySet
```
    View of the keys.
  - values
```
protected transient Collection values
```
    View of the values.
  - entrySet
```
protected transient Set entrySet
```
    View of the entries.
- Constructor Detail
  - AbstractDualBidiMap
```
protected AbstractDualBidiMap()
```
    Creates an empty map, initialised by createMap.
    This constructor remains in place for deserialization. All other usage is deprecated in favour of AbstractDualBidiMap(Map, Map).
  - AbstractDualBidiMap
```
protected AbstractDualBidiMap(Map normalMap,
                              Map reverseMap)
```
    Creates an empty map using the two maps specified as storage.
    The two maps must be a matching pair, normal and reverse. They will typically both be empty.
    Neither map is validated, so nulls may be passed in. If you choose to do this then the subclass constructor must populate the maps[] instance variable itself.
    
    Parameters:
    
    normalMap - the normal direction map
    
    reverseMap - the reverse direction map
    
    Since:
    
    Commons Collections 3.1
  - AbstractDualBidiMap
```
protected AbstractDualBidiMap(Map normalMap,
                              Map reverseMap,
                              BidiMap inverseBidiMap)
```
    Constructs a map that decorates the specified maps, used by the subclass createBidiMap implementation.
    
    Parameters:
    
    normalMap - the normal direction map
    
    reverseMap - the reverse direction map
    
    inverseBidiMap - the inverse BidiMap
- Method Detail
  - createMap
```
protected Map createMap()
```
    Deprecated.
    For constructors, use the new two map constructor. For deserialization, populate the maps array directly in readObject.
    
    Creates a new instance of the map used by the subclass to store data.
    This design is deeply flawed and has been deprecated. It relied on subclass data being used during a superclass constructor.
    
    Returns:
    
    the map to be used for internal storage
  - createBidiMap
```
protected abstract BidiMap createBidiMap(Map normalMap,
                                         Map reverseMap,
                                         BidiMap inverseMap)
```
    Creates a new instance of the subclass.
    
    Parameters:
    
    normalMap - the normal direction map
    
    reverseMap - the reverse direction map
    
    inverseMap - this map, which is the inverse in the new map
    
    Returns:
    
    the inverse map
  - get
```
public Object get(Object key)
```
    Specified by:
    
    get in interface Map
  - size
```
public int size()
```
    Specified by:
    
    size in interface Map
  - isEmpty
```
public boolean isEmpty()
```
    Specified by:
    
    isEmpty in interface Map
  - containsKey
```
public boolean containsKey(Object key)
```
    Specified by:
    
    containsKey in interface Map
  - equals
```
public boolean equals(Object obj)
```
    Specified by:
    
    equals in interface Map
    
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Specified by:
    
    hashCode in interface Map
    
    Overrides:
    
    hashCode in class Object
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - put
```
public Object put(Object key,
                  Object value)
```
    Description copied from interface: BidiMap
    Puts the key-value pair into the map, replacing any previous pair.
    When adding a key-value pair, the value may already exist in the map against a different key. That mapping is removed, to ensure that the value only occurs once in the inverse map.
    BidiMap map1 = new DualHashBidiMap(); map.put("A","B"); // contains A mapped to B, as per Map map.put("A","C"); // contains A mapped to C, as per Map BidiMap map2 = new DualHashBidiMap(); map.put("A","B"); // contains A mapped to B, as per Map map.put("C","B"); // contains C mapped to B, key A is removed
    Specified by:
    
    put in interface BidiMap
    
    Specified by:
    
    put in interface Map
    
    Parameters:
    
    key - the key to store
    
    value - the value to store
    
    Returns:
    
    the previous value mapped to this key
  - putAll
```
public void putAll(Map map)
```
    Specified by:
    
    putAll in interface Map
  - remove
```
public Object remove(Object key)
```
    Specified by:
    
    remove in interface Map
  - clear
```
public void clear()
```
    Specified by:
    
    clear in interface Map
  - containsValue
```
public boolean containsValue(Object value)
```
    Specified by:
    
    containsValue in interface Map
  - mapIterator
```
public MapIterator mapIterator()
```
    Obtains a MapIterator over the map. The iterator implements ResetableMapIterator. This implementation relies on the entrySet iterator.
    The setValue() methods only allow a new value to be set. If the value being set is already in the map, an IllegalArgumentException is thrown (as setValue cannot change the size of the map).
    
    Specified by:
    
    mapIterator in interface BidiMap
    
    Specified by:
    
    mapIterator in interface IterableMap
    
    Returns:
    
    a map iterator
  - getKey
```
public Object getKey(Object value)
```
    Description copied from interface: BidiMap
    
    Gets the key that is currently mapped to the specified value.
    If the value is not contained in the map, null is returned.
    Implementations should seek to make this method perform equally as well as get(Object).
    
    Specified by:
    
    getKey in interface BidiMap
    
    Parameters:
    
    value - the value to find the key for
    
    Returns:
    
    the mapped key, or null if not found
  - removeValue
```
public Object removeValue(Object value)
```
    Description copied from interface: BidiMap
    
    Removes the key-value pair that is currently mapped to the specified value (optional operation).
    If the value is not contained in the map, null is returned.
    Implementations should seek to make this method perform equally as well as remove(Object).
    
    Specified by:
    
    removeValue in interface BidiMap
    
    Parameters:
    
    value - the value to find the key-value pair for
    
    Returns:
    
    the key that was removed, null if nothing removed
  - inverseBidiMap
```
public BidiMap inverseBidiMap()
```
    Description copied from interface: BidiMap
    
    Gets a view of this map where the keys and values are reversed.
    Changes to one map will be visible in the other and vice versa. This enables both directions of the map to be accessed as a Map.
    Implementations should seek to avoid creating a new object every time this method is called. See AbstractMap.values() etc. Calling this method on the inverse map should return the original.
    
    Specified by:
    
    inverseBidiMap in interface BidiMap
    
    Returns:
    
    an inverted bidirectional map
  - keySet
```
public Set keySet()
```
    Gets a keySet view of the map. Changes made on the view are reflected in the map. The set supports remove and clear but not add.
    
    Specified by:
    
    keySet in interface Map
    
    Returns:
    
    the keySet view
  - createKeySetIterator
```
protected Iterator createKeySetIterator(Iterator iterator)
```
    Creates a key set iterator. Subclasses can override this to return iterators with different properties.
    
    Parameters:
    
    iterator - the iterator to decorate
    
    Returns:
    
    the keySet iterator
  - values
```
public Collection values()
```
    Gets a values view of the map. Changes made on the view are reflected in the map. The set supports remove and clear but not add.
    
    Specified by:
    
    values in interface Map
    
    Returns:
    
    the values view
  - createValuesIterator
```
protected Iterator createValuesIterator(Iterator iterator)
```
    Creates a values iterator. Subclasses can override this to return iterators with different properties.
    
    Parameters:
    
    iterator - the iterator to decorate
    
    Returns:
    
    the values iterator
  - entrySet
```
public Set entrySet()
```
    Gets an entrySet view of the map. Changes made on the set are reflected in the map. The set supports remove and clear but not add.
    The Map Entry setValue() method only allow a new value to be set. If the value being set is already in the map, an IllegalArgumentException is thrown (as setValue cannot change the size of the map).
    
    Specified by:
    
    entrySet in interface Map
    
    Returns:
    
    the entrySet view
  - createEntrySetIterator
```
protected Iterator createEntrySetIterator(Iterator iterator)
```
    Creates an entry set iterator. Subclasses can override this to return iterators with different properties.
    
    Parameters:
    
    iterator - the iterator to decorate
    
    Returns:
    
    the entrySet iterator

Class AbstractDualBidiMap

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Map

Field Detail

maps

inverseBidiMap

keySet

values

entrySet

Constructor Detail

AbstractDualBidiMap

AbstractDualBidiMap

AbstractDualBidiMap

Method Detail

createMap

createBidiMap

get

size

isEmpty

containsKey

equals

hashCode

toString

put

putAll

remove

clear

containsValue

mapIterator

getKey

removeValue

inverseBidiMap

keySet

createKeySetIterator

values

createValuesIterator

entrySet

createEntrySetIterator