public final class DoubleOrderedMap
extends java.util.AbstractMap
This Map is intended for applications that need to be able to look up a key-value pairing by either key or value, and need to do so with equal efficiency.
While that goal could be accomplished by taking a pair of TreeMaps
and redirecting requests to the appropriate TreeMap (e.g.,
containsKey would be directed to the TreeMap that maps values to
keys, containsValue would be directed to the TreeMap that maps keys
to values), there are problems with that implementation,
particularly when trying to keep the two TreeMaps synchronized with
each other. And if the data contained in the TreeMaps is large, the
cost of redundant storage becomes significant. (See also the new
DualTreeBidiMap
and
DualHashBidiMap
implementations.)
This solution keeps the data properly synchronized and minimizes the data storage. The red-black algorithm is based on TreeMap's, but has been modified to simultaneously map a tree node by key and by value. This doubles the cost of put operations (but so does using two TreeMaps), and nearly doubles the cost of remove operations (there is a savings in that the lookup of the node to be removed only has to be performed once). And since only one node contains the key and value, storage is significantly less than that required by two TreeMaps.
There are some limitations placed on data kept in this Map. The biggest one is this:
When performing a put operation, neither the key nor the value may already exist in the Map. In the java.util Map implementations (HashMap, TreeMap), you can perform a put with an already mapped key, and neither cares about duplicate values at all ... but this implementation's put method with throw an IllegalArgumentException if either the key or the value is already in the Map.
Obviously, that same restriction (and consequence of failing to heed that restriction) applies to the putAll method.
The Map.Entry instances returned by the appropriate methods will not allow setValue() and will throw an UnsupportedOperationException on attempts to call that method.
New methods are added to take advantage of the fact that values are kept sorted independently of their keys:
Object getKeyForValue(Object value) is the opposite of get; it takes a value and returns its key, if any.
Object removeValue(Object value) finds and removes the specified value and returns the now un-used key.
Set entrySetByValue() returns the Map.Entry's in a Set whose iterator will iterate over the Map.Entry's in ascending order by their corresponding values.
Set keySetByValue() returns the keys in a Set whose iterator will iterate over the keys in ascending order by their corresponding values.
Collection valuesByValue() returns the values in a Collection whose iterator will iterate over the values in ascending order.
BidiMap
,
DualTreeBidiMap
,
DualHashBidiMap
Modifier and Type | Class and Description |
---|---|
private class |
DoubleOrderedMap.DoubleOrderedMapIterator
Deprecated.
|
private static class |
DoubleOrderedMap.Node
Deprecated.
|
Modifier and Type | Field and Description |
---|---|
private java.util.Collection[] |
collectionOfValues
Deprecated.
|
private static java.lang.String[] |
dataName
Deprecated.
|
private static int |
FIRST_INDEX
Deprecated.
|
private static int |
KEY
Deprecated.
|
private int |
modifications
Deprecated.
|
private int |
nodeCount
Deprecated.
|
private static int |
NUMBER_OF_INDICES
Deprecated.
|
private DoubleOrderedMap.Node[] |
rootNode
Deprecated.
|
private java.util.Set[] |
setOfEntries
Deprecated.
|
private java.util.Set[] |
setOfKeys
Deprecated.
|
private static int |
SUM_OF_INDICES
Deprecated.
|
private static int |
VALUE
Deprecated.
|
Constructor and Description |
---|
DoubleOrderedMap()
Deprecated.
Construct a new DoubleOrderedMap
|
DoubleOrderedMap(java.util.Map map)
Deprecated.
Constructs a new DoubleOrderedMap from an existing Map, with keys and
values sorted
|
Modifier and Type | Method and Description |
---|---|
private static void |
checkKey(java.lang.Object key)
Deprecated.
check a key for validity (non-null and implements Comparable)
|
private static void |
checkKeyAndValue(java.lang.Object key,
java.lang.Object value)
Deprecated.
check a key and a value for validity (non-null and implements
Comparable)
|
private static void |
checkNonNullComparable(java.lang.Object o,
int index)
Deprecated.
check if an object is fit to be proper input ...
|
private static void |
checkValue(java.lang.Object value)
Deprecated.
check a value for validity (non-null and implements Comparable)
|
void |
clear()
Deprecated.
Removes all mappings from this map
|
private static int |
compare(java.lang.Comparable o1,
java.lang.Comparable o2)
Deprecated.
Compare two objects
|
boolean |
containsKey(java.lang.Object key)
Deprecated.
Returns true if this map contains a mapping for the specified
key.
|
boolean |
containsValue(java.lang.Object value)
Deprecated.
Returns true if this map maps one or more keys to the
specified value.
|
private static void |
copyColor(DoubleOrderedMap.Node from,
DoubleOrderedMap.Node to,
int index)
Deprecated.
copy the color from one node to another, dealing with the fact
that one or both nodes may, in fact, be null
|
private java.lang.Object |
doGet(java.lang.Comparable o,
int index)
Deprecated.
common get logic, used to get by key or get by value
|
private void |
doRedBlackDelete(DoubleOrderedMap.Node deletedNode)
Deprecated.
complicated red-black delete stuff.
|
private void |
doRedBlackDeleteFixup(DoubleOrderedMap.Node replacementNode,
int index)
Deprecated.
complicated red-black delete stuff.
|
private void |
doRedBlackInsert(DoubleOrderedMap.Node insertedNode,
int index)
Deprecated.
complicated red-black insert stuff.
|
private java.lang.Object |
doRemove(java.lang.Comparable o,
int index)
Deprecated.
common remove logic (remove by key or remove by value)
|
java.util.Set |
entrySet()
Deprecated.
Returns a set view of the mappings contained in this map.
|
java.util.Set |
entrySetByValue()
Deprecated.
Returns a set view of the mappings contained in this map.
|
java.lang.Object |
get(java.lang.Object key)
Deprecated.
Returns the value to which this map maps the specified
key.
|
private static DoubleOrderedMap.Node |
getGrandParent(DoubleOrderedMap.Node node,
int index)
Deprecated.
get a node's grandparent.
|
java.lang.Object |
getKeyForValue(java.lang.Object value)
Deprecated.
Returns the key to which this map maps the specified value.
|
private static DoubleOrderedMap.Node |
getLeftChild(DoubleOrderedMap.Node node,
int index)
Deprecated.
get a node's left child.
|
private static DoubleOrderedMap.Node |
getParent(DoubleOrderedMap.Node node,
int index)
Deprecated.
get a node's parent.
|
private static DoubleOrderedMap.Node |
getRightChild(DoubleOrderedMap.Node node,
int index)
Deprecated.
get a node's right child.
|
private void |
grow()
Deprecated.
bump up the size and note that the map has changed
|
private void |
insertValue(DoubleOrderedMap.Node newNode)
Deprecated.
insert a node by its value
|
private static boolean |
isBlack(DoubleOrderedMap.Node node,
int index)
Deprecated.
is the specified black red? if the node does not exist, sure,
it's black, thank you
|
private static boolean |
isLeftChild(DoubleOrderedMap.Node node,
int index)
Deprecated.
is this node its parent's left child? mind you, the node, or
its parent, may not exist.
|
private static boolean |
isRed(DoubleOrderedMap.Node node,
int index)
Deprecated.
is the specified node red? if the node does not exist, no, it's
black, thank you
|
private static boolean |
isRightChild(DoubleOrderedMap.Node node,
int index)
Deprecated.
is this node its parent's right child? mind you, the node, or
its parent, may not exist.
|
java.util.Set |
keySet()
Deprecated.
Returns a set view of the keys contained in this map.
|
java.util.Set |
keySetByValue()
Deprecated.
Returns a set view of the keys contained in this map.
|
private static DoubleOrderedMap.Node |
leastNode(DoubleOrderedMap.Node node,
int index)
Deprecated.
find the least node from a given node.
|
private DoubleOrderedMap.Node |
lookup(java.lang.Comparable data,
int index)
Deprecated.
do the actual lookup of a piece of data
|
private static void |
makeBlack(DoubleOrderedMap.Node node,
int index)
Deprecated.
force a node (if it exists) black
|
private static void |
makeRed(DoubleOrderedMap.Node node,
int index)
Deprecated.
force a node (if it exists) red
|
private void |
modify()
Deprecated.
increment the modification count -- used to check for
concurrent modification of the map through the map and through
an Iterator from one of its Set or Collection views
|
private DoubleOrderedMap.Node |
nextGreater(DoubleOrderedMap.Node node,
int index)
Deprecated.
get the next larger node from the specified node
|
private int |
oppositeIndex(int index)
Deprecated.
Get the opposite index of the specified index
|
java.lang.Object |
put(java.lang.Object key,
java.lang.Object value)
Deprecated.
Associates the specified value with the specified key in this
map.
|
java.lang.Object |
remove(java.lang.Object key)
Deprecated.
Removes the mapping for this key from this map if present
|
java.lang.Object |
removeValue(java.lang.Object value)
Deprecated.
Removes the mapping for this value from this map if present
|
private void |
rotateLeft(DoubleOrderedMap.Node node,
int index)
Deprecated.
do a rotate left.
|
private void |
rotateRight(DoubleOrderedMap.Node node,
int index)
Deprecated.
do a rotate right.
|
private void |
shrink()
Deprecated.
decrement the size and note that the map has changed
|
int |
size()
Deprecated.
Returns the number of key-value mappings in this map.
|
private void |
swapPosition(DoubleOrderedMap.Node x,
DoubleOrderedMap.Node y,
int index)
Deprecated.
swap two nodes (except for their content), taking care of
special cases where one is the other's parent ...
|
java.util.Collection |
values()
Deprecated.
Returns a collection view of the values contained in this
map.
|
java.util.Collection |
valuesByValue()
Deprecated.
Returns a collection view of the values contained in this
map.
|
clone, equals, hashCode, isEmpty, putAll, toString
private static final int KEY
private static final int VALUE
private static final int SUM_OF_INDICES
private static final int FIRST_INDEX
private static final int NUMBER_OF_INDICES
private static final java.lang.String[] dataName
private DoubleOrderedMap.Node[] rootNode
private int nodeCount
private int modifications
private java.util.Set[] setOfKeys
private java.util.Set[] setOfEntries
private java.util.Collection[] collectionOfValues
public DoubleOrderedMap()
public DoubleOrderedMap(java.util.Map map) throws java.lang.ClassCastException, java.lang.NullPointerException, java.lang.IllegalArgumentException
map
- the map whose mappings are to be placed in this map.java.lang.ClassCastException
- if the keys in the map are not
Comparable, or are not mutually
comparable; also if the values in
the map are not Comparable, or
are not mutually Comparablejava.lang.NullPointerException
- if any key or value in the map
is nulljava.lang.IllegalArgumentException
- if there are duplicate keys
or duplicate values in the
mappublic java.lang.Object getKeyForValue(java.lang.Object value) throws java.lang.ClassCastException, java.lang.NullPointerException
value
- value whose associated key is to be returned.java.lang.ClassCastException
- if the value is of an
inappropriate type for this map.java.lang.NullPointerException
- if the value is nullpublic java.lang.Object removeValue(java.lang.Object value)
value
- value whose mapping is to be removed from the map.public java.util.Set entrySetByValue()
The difference between this method and entrySet is that entrySet's iterator() method returns an iterator that iterates over the mappings in ascending order by key. This method's iterator method iterates over the mappings in ascending order by value.
public java.util.Set keySetByValue()
The difference between this method and keySet is that keySet's iterator() method returns an iterator that iterates over the keys in ascending order by key. This method's iterator method iterates over the keys in ascending order by value.
public java.util.Collection valuesByValue()
The difference between this method and values is that values's iterator() method returns an iterator that iterates over the values in ascending order by key. This method's iterator method iterates over the values in ascending order by key.
private java.lang.Object doRemove(java.lang.Comparable o, int index)
o
- the key, or value, that we're looking forindex
- KEY or VALUEprivate java.lang.Object doGet(java.lang.Comparable o, int index)
o
- the key or value that we're looking forindex
- KEY or VALUEprivate int oppositeIndex(int index)
index
- KEY or VALUEprivate DoubleOrderedMap.Node lookup(java.lang.Comparable data, int index)
data
- the key or value to be looked upindex
- KEY or VALUEprivate static int compare(java.lang.Comparable o1, java.lang.Comparable o2)
o1
- the first objecto2
- the second objectprivate static DoubleOrderedMap.Node leastNode(DoubleOrderedMap.Node node, int index)
node
- the node from which we will start searchingindex
- KEY or VALUEprivate DoubleOrderedMap.Node nextGreater(DoubleOrderedMap.Node node, int index)
node
- the node to be searched fromindex
- KEY or VALUEprivate static void copyColor(DoubleOrderedMap.Node from, DoubleOrderedMap.Node to, int index)
from
- the node whose color we're copying; may be nullto
- the node whose color we're changing; may be nullindex
- KEY or VALUEprivate static boolean isRed(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static boolean isBlack(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static void makeRed(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static void makeBlack(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static DoubleOrderedMap.Node getGrandParent(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static DoubleOrderedMap.Node getParent(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static DoubleOrderedMap.Node getRightChild(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static DoubleOrderedMap.Node getLeftChild(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static boolean isLeftChild(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate static boolean isRightChild(DoubleOrderedMap.Node node, int index)
node
- the node (may be null) in questionindex
- KEY or VALUEprivate void rotateLeft(DoubleOrderedMap.Node node, int index)
node
- the node to be rotatedindex
- KEY or VALUEprivate void rotateRight(DoubleOrderedMap.Node node, int index)
node
- the node to be rotatedindex
- KEY or VALUEprivate void doRedBlackInsert(DoubleOrderedMap.Node insertedNode, int index)
insertedNode
- the node to be insertedindex
- KEY or VALUEprivate void doRedBlackDelete(DoubleOrderedMap.Node deletedNode)
deletedNode
- the node to be deletedprivate void doRedBlackDeleteFixup(DoubleOrderedMap.Node replacementNode, int index)
replacementNode
- the node being replacedindex
- KEY or VALUEprivate void swapPosition(DoubleOrderedMap.Node x, DoubleOrderedMap.Node y, int index)
x
- one nodey
- another nodeindex
- KEY or VALUEprivate static void checkNonNullComparable(java.lang.Object o, int index)
o
- the object being checkedindex
- KEY or VALUE (used to put the right word in the
exception message)java.lang.NullPointerException
- if o is nulljava.lang.ClassCastException
- if o is not Comparableprivate static void checkKey(java.lang.Object key)
key
- the key to be checkedjava.lang.NullPointerException
- if key is nulljava.lang.ClassCastException
- if key is not Comparableprivate static void checkValue(java.lang.Object value)
value
- the value to be checkedjava.lang.NullPointerException
- if value is nulljava.lang.ClassCastException
- if value is not Comparableprivate static void checkKeyAndValue(java.lang.Object key, java.lang.Object value)
key
- the key to be checkedvalue
- the value to be checkedjava.lang.NullPointerException
- if key or value is nulljava.lang.ClassCastException
- if key or value is not Comparableprivate void modify()
private void grow()
private void shrink()
private void insertValue(DoubleOrderedMap.Node newNode) throws java.lang.IllegalArgumentException
newNode
- the node to be insertedjava.lang.IllegalArgumentException
- if the node already exists
in the value mappingpublic int size()
size
in interface java.util.Map
size
in class java.util.AbstractMap
public boolean containsKey(java.lang.Object key) throws java.lang.ClassCastException, java.lang.NullPointerException
containsKey
in interface java.util.Map
containsKey
in class java.util.AbstractMap
key
- key whose presence in this map is to be tested.java.lang.ClassCastException
- if the key is of an inappropriate
type for this map.java.lang.NullPointerException
- if the key is nullpublic boolean containsValue(java.lang.Object value)
containsValue
in interface java.util.Map
containsValue
in class java.util.AbstractMap
value
- value whose presence in this map is to be tested.public java.lang.Object get(java.lang.Object key) throws java.lang.ClassCastException, java.lang.NullPointerException
get
in interface java.util.Map
get
in class java.util.AbstractMap
key
- key whose associated value is to be returned.java.lang.ClassCastException
- if the key is of an inappropriate
type for this map.java.lang.NullPointerException
- if the key is nullpublic java.lang.Object put(java.lang.Object key, java.lang.Object value) throws java.lang.ClassCastException, java.lang.NullPointerException, java.lang.IllegalArgumentException
put
in interface java.util.Map
put
in class java.util.AbstractMap
key
- key with which the specified value is to be
associated.value
- value to be associated with the specified key.java.lang.ClassCastException
- if the class of the specified key
or value prevents it from being
stored in this map.java.lang.NullPointerException
- if the specified key or value
is nulljava.lang.IllegalArgumentException
- if the key duplicates an
existing key, or if the
value duplicates an
existing valuepublic java.lang.Object remove(java.lang.Object key)
remove
in interface java.util.Map
remove
in class java.util.AbstractMap
key
- key whose mapping is to be removed from the map.public void clear()
clear
in interface java.util.Map
clear
in class java.util.AbstractMap
public java.util.Set keySet()
keySet
in interface java.util.Map
keySet
in class java.util.AbstractMap
public java.util.Collection values()
values
in interface java.util.Map
values
in class java.util.AbstractMap
public java.util.Set entrySet()
The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove, removeAll, retainAll and clear operations. It does not support the add or addAll operations. The setValue method is not supported on the Map Entry.
entrySet
in interface java.util.Map
entrySet
in class java.util.AbstractMap