org.apache.commons.collections.bidimap

Class TreeBidiMap.Inverse

java.lang.Object

org.apache.commons.collections.bidimap.TreeBidiMap.Inverse

All Implemented Interfaces:

java.util.Map, BidiMap, IterableMap, OrderedBidiMap, OrderedMap

Enclosing class:

TreeBidiMap

static class TreeBidiMap.Inverse
extends java.lang.Object
implements OrderedBidiMap

A node used to store the data.

Nested Class Summary

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

java.util.Map.Entry<K,V>

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Set	entrySet Store the entrySet once created.
private java.util.Set	keySet Store the keySet once created.
private TreeBidiMap	main The parent map.
private java.util.Set	valuesSet Store the valuesSet once created.

Constructor Summary

Constructors

Constructor and Description
Inverse(TreeBidiMap main) Constructor.

Method Summary

Modifier and Type	Method and Description
void	clear()
boolean	containsKey(java.lang.Object key)
boolean	containsValue(java.lang.Object value)
java.util.Set	entrySet()
boolean	equals(java.lang.Object obj)
java.lang.Object	firstKey() Gets the first key currently in this map.
java.lang.Object	get(java.lang.Object key)
java.lang.Object	getKey(java.lang.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.
OrderedBidiMap	inverseOrderedBidiMap() Gets a view of this map where the keys and values are reversed.
boolean	isEmpty()
java.util.Set	keySet()
java.lang.Object	lastKey() Gets the last key currently in this map.
MapIterator	mapIterator() Obtains a MapIterator over the map.
java.lang.Object	nextKey(java.lang.Object key) Gets the next key after the one specified.
OrderedMapIterator	orderedMapIterator() Obtains an OrderedMapIterator over the map.
java.lang.Object	previousKey(java.lang.Object key) Gets the previous key before the one specified.
java.lang.Object	put(java.lang.Object key, java.lang.Object value) Puts the key-value pair into the map, replacing any previous pair.
void	putAll(java.util.Map map)
java.lang.Object	remove(java.lang.Object key)
java.lang.Object	removeValue(java.lang.Object value) Removes the key-value pair that is currently mapped to the specified value (optional operation).
int	size()
java.lang.String	toString()
java.util.Collection	values()

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

main

private final TreeBidiMap main

The parent map.

keySet

private java.util.Set keySet

Store the keySet once created.

valuesSet

private java.util.Set valuesSet

Store the valuesSet once created.

entrySet

private java.util.Set entrySet

Store the entrySet once created.

Constructor Detail

Inverse

Inverse(TreeBidiMap main)

Constructor.

Parameters:

main - the main map

Method Detail

size

public int size()

Specified by:

size in interface java.util.Map

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface java.util.Map

get

public java.lang.Object get(java.lang.Object key)

Specified by:

get in interface java.util.Map

getKey

public java.lang.Object getKey(java.lang.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

containsKey

public boolean containsKey(java.lang.Object key)

Specified by:

containsKey in interface java.util.Map

containsValue

public boolean containsValue(java.lang.Object value)

Specified by:

containsValue in interface java.util.Map

firstKey

public java.lang.Object firstKey()

Description copied from interface: OrderedMap

Gets the first key currently in this map.

Specified by:

firstKey in interface OrderedMap

Returns:

the first key currently in this map

lastKey

public java.lang.Object lastKey()

Description copied from interface: OrderedMap

Gets the last key currently in this map.

Specified by:

lastKey in interface OrderedMap

Returns:

the last key currently in this map

nextKey

public java.lang.Object nextKey(java.lang.Object key)

Description copied from interface: OrderedMap

Gets the next key after the one specified.

Specified by:

nextKey in interface OrderedMap

Parameters:

key - the key to search for next from

Returns:

the next key, null if no match or at end

previousKey

public java.lang.Object previousKey(java.lang.Object key)

Description copied from interface: OrderedMap

Gets the previous key before the one specified.

Specified by:

previousKey in interface OrderedMap

Parameters:

key - the key to search for previous from

Returns:

the previous key, null if no match or at start

put

public java.lang.Object put(java.lang.Object key,
                            java.lang.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 java.util.Map

Specified by:

put in interface BidiMap

Parameters:

key - the key to store

value - the value to store

Returns:

the previous value mapped to this key

putAll

public void putAll(java.util.Map map)

Specified by:

putAll in interface java.util.Map

remove

public java.lang.Object remove(java.lang.Object key)

Specified by:

remove in interface java.util.Map

removeValue

public java.lang.Object removeValue(java.lang.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

clear

public void clear()

Specified by:

clear in interface java.util.Map

keySet

public java.util.Set keySet()

Specified by:

keySet in interface java.util.Map

values

public java.util.Collection values()

Specified by:

values in interface java.util.Map

entrySet

public java.util.Set entrySet()

Specified by:

entrySet in interface java.util.Map

mapIterator

public MapIterator mapIterator()

Description copied from interface: BidiMap

Obtains a MapIterator over the map.

A map iterator is an efficient way of iterating over maps. It does not require that the map is stored using Map Entry objects which can increase performance.

 BidiMap map = new DualHashBidiMap();
 MapIterator it = map.mapIterator();
 while (it.hasNext()) {
   Object key = it.next();
   Object value = it.getValue();
   it.setValue("newValue");
 }
 

Specified by:

mapIterator in interface BidiMap

Specified by:

mapIterator in interface IterableMap

Returns:

a map iterator

orderedMapIterator

public OrderedMapIterator orderedMapIterator()

Description copied from interface: OrderedMap

Obtains an OrderedMapIterator over the map.

A ordered map iterator is an efficient way of iterating over maps in both directions.

 BidiMap map = new TreeBidiMap();
 MapIterator it = map.mapIterator();
 while (it.hasNext()) {
   Object key = it.next();
   Object value = it.getValue();
   it.setValue("newValue");
   Object previousKey = it.previous();
 }
 

Specified by:

orderedMapIterator in interface OrderedMap

Returns:

a map iterator

inverseBidiMap

public BidiMap inverseBidiMap()

Description copied from interface: OrderedBidiMap

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 equally.

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.

Implementations must return an OrderedBidiMap instance, usually by forwarding to inverseOrderedBidiMap().

Specified by:

inverseBidiMap in interface BidiMap

Specified by:

inverseBidiMap in interface OrderedBidiMap

Returns:

an inverted bidirectional map

inverseOrderedBidiMap

public OrderedBidiMap inverseOrderedBidiMap()

Description copied from interface: OrderedBidiMap

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 equally.

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:

inverseOrderedBidiMap in interface OrderedBidiMap

Returns:

an inverted bidirectional map

equals

public boolean equals(java.lang.Object obj)

Specified by:

equals in interface java.util.Map

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Specified by:

hashCode in interface java.util.Map

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object