fj.data

Class TreeMap<K,V>

java.lang.Object

fj.data.TreeMap<K,V>

All Implemented Interfaces:

java.lang.Iterable<P2<K,V>>

public final class TreeMap<K,V>
extends java.lang.Object
implements java.lang.Iterable<P2<K,V>>

An immutable, in-memory map, backed by a red-black tree.

Method Summary

Modifier and Type	Method and Description
static <K,V> TreeMap<K,V>	arrayTreeMap(Ord<K> keyOrd, P2<K,V>... ps) Constructs a tree map from the given elements.
boolean	contains(K k) Determines if the given key value exists in this tree map.
TreeMap<K,V>	delete(K k) Deletes the entry in the tree map that corresponds to the given key.
static <K,V> TreeMap<K,V>	empty(Ord<K> keyOrd) Constructs an empty tree map.
boolean	equals(java.lang.Object other)
static <K,V> TreeMap<K,V>	fromMutableMap(Ord<K> ord, java.util.Map<K,V> m) An immutable projection of the given mutable map.
F<K,Option<V>>	get() Returns a first-class version of the get method for this TreeMap.
Option<V>	get(K k) Returns a potential value that the given key maps to.
int	hashCode()
boolean	isEmpty() Determines if this tree map has any entries.
static <K,V> TreeMap<K,V>	iterableTreeMap(Ord<K> keyOrd, java.lang.Iterable<P2<K,V>> it) Constructs a tree map from the given elements.
java.util.Iterator<P2<K,V>>	iterator() Returns an iterator for this map's key-value pairs.
static <K,V> TreeMap<K,V>	iteratorTreeMap(Ord<K> keyOrd, java.util.Iterator<P2<K,V>> it) Constructs a tree map from the given elements.
List<K>	keys() Returns all keys in this tree map.
<W> TreeMap<K,W>	map(F<V,W> f) Maps the given function across the values of this TreeMap.
Option<P2<K,V>>	max() Returns the maximum (key, value) pair in the tree if the tree is not empty.
Option<K>	maxKey() Returns the maximum key in the tree if the tree is not empty.
Option<P2<K,V>>	min() Returns the minimum (key, value) pair in the tree if the tree is not empty.
Option<K>	minKey() Returns the minimum key in the tree if the tree is not empty.
TreeMap<K,V>	set(K k, V v) Inserts the given key and value association into the tree map.
int	size() Returns the number of entries in this tree map.
P3<Set<V>,Option<V>,Set<V>>	split(Ord<V> ord, K k) Splits this TreeMap at the given key.
P3<TreeMap<K,V>,Option<V>,TreeMap<K,V>>	splitLookup(K k) Splits this TreeMap at the given key.
List<P2<K,V>>	toList()
List<P2<K,V>>	toListReverse()
java.util.Map<K,V>	toMutableMap() A mutable map projection of this tree map.
Stream<P2<K,V>>	toStream()
Stream<P2<K,V>>	toStreamReverse()
java.lang.String	toString()
static <K,V> TreeMap<K,V>	treeMap(Ord<K> keyOrd, List<P2<K,V>> list) Deprecated. As of release 4.5, use iterableTreeMap(Ord, Iterable)
static <K,V> TreeMap<K,V>	treeMap(Ord<K> keyOrd, P2<K,V>... p2s) Constructs a tree map from the given elements.
TreeMap<K,V>	union(java.lang.Iterable<P2<K,V>> t2) The expression t1.union(t2) takes the left-biased union of t1 and t2.
TreeMap<K,V>	union(TreeMap<K,V> t2) The expression t1.union(t2) takes the left-biased union of t1 and t2.
P2<java.lang.Boolean,TreeMap<K,V>>	update(K k, F<V,V> f) Modifies the value for the given key, if present, by applying the given function to it.
TreeMap<K,V>	update(K k, F<V,V> f, V v) Modifies the value for the given key, if present, by applying the given function to it, or inserts the given value if the key is not present.
List<V>	values() Returns all values in this tree map.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

empty

public static <K,V> TreeMap<K,V> empty(Ord<K> keyOrd)

Constructs an empty tree map.

Parameters:

keyOrd - An order for the keys of the tree map.

Returns:

an empty TreeMap with the given key order.

equals

public boolean equals(java.lang.Object other)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

treeMap

@SafeVarargs
public static <K,V> TreeMap<K,V> treeMap(Ord<K> keyOrd,
                                                       P2<K,V>... p2s)

Constructs a tree map from the given elements.

Parameters:

keyOrd - An order for the keys of the tree map.

p2s - The elements to construct the tree map with.

Returns:

a TreeMap with the given elements.

treeMap

@Deprecated
public static <K,V> TreeMap<K,V> treeMap(Ord<K> keyOrd,
                                                      List<P2<K,V>> list)

Deprecated. As of release 4.5, use iterableTreeMap(Ord, Iterable)

Constructs a tree map from the given elements.

Parameters:

keyOrd - An order for the keys of the tree map.

list - The elements to construct the tree map with.

Returns:

a TreeMap with the given elements.

iterableTreeMap

public static <K,V> TreeMap<K,V> iterableTreeMap(Ord<K> keyOrd,
                                                 java.lang.Iterable<P2<K,V>> it)

Constructs a tree map from the given elements.

Parameters:

keyOrd - An order for the keys of the tree map.

it - The elements to construct the tree map with.

Returns:

A TreeMap with the given elements.

iteratorTreeMap

public static <K,V> TreeMap<K,V> iteratorTreeMap(Ord<K> keyOrd,
                                                 java.util.Iterator<P2<K,V>> it)

Constructs a tree map from the given elements.

Parameters:

keyOrd - An order for the keys of the tree map.

it - The elements to construct the tree map with.

Returns:

A TreeMap with the given elements.

arrayTreeMap

@SafeVarargs
public static <K,V> TreeMap<K,V> arrayTreeMap(Ord<K> keyOrd,
                                                            P2<K,V>... ps)

Constructs a tree map from the given elements.

Parameters:

keyOrd - An order for the keys of the tree map.

ps - The elements to construct the tree map with.

Returns:

A TreeMap with the given elements.

get

public Option<V> get(K k)

Returns a potential value that the given key maps to.

Parameters:

k - The key to look up in the tree map.

Returns:

A potential value for the given key.

set

public TreeMap<K,V> set(K k,
                        V v)

Inserts the given key and value association into the tree map. If the given key is already mapped to a value, the old value is replaced with the given one.

Parameters:

k - The key to insert.

v - The value to insert.

Returns:

A new tree map with the given value mapped to the given key.

delete

public TreeMap<K,V> delete(K k)

Deletes the entry in the tree map that corresponds to the given key.

Parameters:

k - The key to delete from this tree map.

Returns:

A new tree map with the entry corresponding to the given key removed.

size

public int size()

Returns the number of entries in this tree map.

Returns:

The number of entries in this tree map.

isEmpty

public boolean isEmpty()

Determines if this tree map has any entries.

Returns:

true if this tree map has no entries, false otherwise.

values

public List<V> values()

Returns all values in this tree map.

Returns:

All values in this tree map.

keys

public List<K> keys()

Returns all keys in this tree map.

Returns:

All keys in this tree map.

contains

public boolean contains(K k)

Determines if the given key value exists in this tree map.

Parameters:

k - The key value to look for in this tree map.

Returns:

true if this tree map contains the given key, false otherwise.

iterator

public java.util.Iterator<P2<K,V>> iterator()

Returns an iterator for this map's key-value pairs. This method exists to permit the use in a for-each loop.

Specified by:

iterator in interface java.lang.Iterable<P2<K,V>>

Returns:

A iterator for this map's key-value pairs.

toMutableMap

public java.util.Map<K,V> toMutableMap()

A mutable map projection of this tree map.

Returns:

A new mutable map isomorphic to this tree map.

toStream

public Stream<P2<K,V>> toStream()

toStreamReverse

public Stream<P2<K,V>> toStreamReverse()

toList

public List<P2<K,V>> toList()

toListReverse

public List<P2<K,V>> toListReverse()

fromMutableMap

public static <K,V> TreeMap<K,V> fromMutableMap(Ord<K> ord,
                                                java.util.Map<K,V> m)

An immutable projection of the given mutable map.

Parameters:

ord - An order for the map's keys.

m - A mutable map to project to an immutable one.

Returns:

A new immutable tree map isomorphic to the given mutable map.

get

public F<K,Option<V>> get()

Returns a first-class version of the get method for this TreeMap.

Returns:

a functional representation of this TreeMap.

update

public P2<java.lang.Boolean,TreeMap<K,V>> update(K k,
                                                 F<V,V> f)

Modifies the value for the given key, if present, by applying the given function to it.

Parameters:

k - The key for the value to modify.

f - A function with which to modify the value.

Returns:

A new tree map with the value for the given key transformed by the given function, paired with True if the map was modified, otherwise False.

update

public TreeMap<K,V> update(K k,
                           F<V,V> f,
                           V v)

Modifies the value for the given key, if present, by applying the given function to it, or inserts the given value if the key is not present.

Parameters:

k - The key for the value to modify.

f - A function with which to modify the value.

v - A value to associate with the given key if the key is not already present.

Returns:

A new tree map with the value for the given key transformed by the given function.

split

public P3<Set<V>,Option<V>,Set<V>> split(Ord<V> ord,
                                         K k)

Splits this TreeMap at the given key. Returns a triple of:

• A set containing all the values of this map associated with keys less than the given key.
• An option of a value mapped to the given key, if it exists in this map, otherwise None.
• A set containing all the values of this map associated with keys greater than the given key.

Parameters:

k - A key at which to split this map.

Returns:

Two sets and an optional value, where all elements in the first set are mapped to keys less than the given key in this map, all the elements in the second set are mapped to keys greater than the given key, and the optional value is the value associated with the given key if present, otherwise None.

splitLookup

public P3<TreeMap<K,V>,Option<V>,TreeMap<K,V>> splitLookup(K k)

Splits this TreeMap at the given key. Returns a triple of:

• A tree map containing all the values of this map associated with keys less than the given key.
• An option of a value mapped to the given key, if it exists in this map, otherwise None.
• A tree map containing all the values of this map associated with keys greater than the given key.

Parameters:

k - A key at which to split this map.

Returns:

Two tree maps and an optional value, where all keys in the first tree map are mapped to keys less than the given key in this map, all the keys in the second tree map are mapped to keys greater than the given key, and the optional value is the value associated with the given key if present, otherwise None.

map

public <W> TreeMap<K,W> map(F<V,W> f)

Maps the given function across the values of this TreeMap.

Parameters:

f - A function to apply to the values of this TreeMap.

Returns:

A new TreeMap with the values transformed by the given function.

min

public Option<P2<K,V>> min()

Returns the minimum (key, value) pair in the tree if the tree is not empty.

minKey

public Option<K> minKey()

Returns the minimum key in the tree if the tree is not empty.

max

public Option<P2<K,V>> max()

Returns the maximum (key, value) pair in the tree if the tree is not empty.

maxKey

public Option<K> maxKey()

Returns the maximum key in the tree if the tree is not empty.

union

public TreeMap<K,V> union(TreeMap<K,V> t2)

The expression t1.union(t2) takes the left-biased union of t1 and t2. It prefers t1 when duplicate keys are encountered.

Parameters:

t2 - The other tree we wish to combine with this one

Returns:

The combined TreeMap

union

public TreeMap<K,V> union(java.lang.Iterable<P2<K,V>> t2)

The expression t1.union(t2) takes the left-biased union of t1 and t2. It prefers t1 when duplicate keys are encountered.

Parameters:

t2 - The other list/set of pairs we wish to combine with this one

Returns:

The combined TreeMap