dart:collection

SplayTreeMap<K, V> class

A Map of objects that can be ordered relative to each other.

The map is based on a self-balancing binary tree. It allows most operations in amortized logarithmic time.

Keys of the map are compared using the compare function passed in the constructor, both for ordering and for equality. If the map contains only the key a, then map.containsKey(b) will return true if and only if compare(a, b) == 0, and the value of a == b is not even checked. If the compare function is omitted, the objects are assumed to be Comparable, and are compared using their Comparable.compareTo method. Non-comparable objects (including null) will not work as keys in that case.

To allow calling operator [], remove or containsKey with objects that are not supported by the compare function, an extra isValidKey predicate function can be supplied. This function is tested before using the compare function on an argument value that may not be a K value. If omitted, the isValidKey function defaults to testing if the value is a K.

Mixed in types

• MapMixin<K, V>

Constructors

SplayTreeMap([int compare(K key1, K key2), bool isValidKey(dynamic potentialKey)])

SplayTreeMap.from(Map other, [int compare(K key1, K key2), bool isValidKey(dynamic potentialKey)])

factory

Creates a SplayTreeMap that contains all key/value pairs of other. [...]

SplayTreeMap.fromIterable(Iterable iterable, {K key(dynamic element), V value(dynamic element), int compare(K key1, K key2), bool isValidKey(dynamic potentialKey)})

factory

Creates a SplayTreeMap where the keys and values are computed from the iterable. [...]

SplayTreeMap.fromIterables(Iterable<K> keys, Iterable<V> values, [int compare(K key1, K key2), bool isValidKey(dynamic potentialKey)])

factory

Creates a SplayTreeMap associating the given keys to values. [...]

SplayTreeMap.of(Map<K, V> other, [int compare(K key1, K key2), bool isValidKey(dynamic potentialKey)])

factory

Creates a SplayTreeMap that contains all key/value pairs of other.

Properties

entries → Iterable<MapEntry<K, V>>

read-only, inherited

The map entries of this.

hashCode → int

read-only, inherited

The hash code for this object. [...]

isEmpty → bool

read-only, override

Whether there is no key/value pair in the map.

isNotEmpty → bool

read-only, override

Whether there is at least one key/value pair in the map.

keys → Iterable<K>

read-only, override

The keys of this. [...]

length → int

read-only, override

The number of key/value pairs in the map.

runtimeType → Type

read-only, inherited

A representation of the runtime type of the object.

values → Iterable<V>

read-only, override

The values of this. [...]

Methods

addAll(Map<K, V> other) → void

override

Adds all key/value pairs of other to this map. [...]

addEntries(Iterable<MapEntry<K, V>> newEntries) → void

inherited

Adds all key/value pairs of newEntries to this map. [...]

cast<RK, RV>() → Map<RK, RV>

inherited

Provides a view of this map as having RK keys and RV instances, if necessary. [...]

clear() → void

override

Removes all entries from the map. [...]

containsKey(Object? key) → bool

override

Whether this map contains the given key. [...]

containsValue(Object? value) → bool

override

Whether this map contains the given value. [...]

firstKey() → K?

The first key in the map. [...]

firstKeyAfter(K key) → K?

Get the first key in the map that is strictly larger than key. Returns null if no key was not found.

forEach(void f(K key, V value)) → void

override

Applies action to each key/value pair of the map. [...]

lastKey() → K?

The last key in the map. [...]

lastKeyBefore(K key) → K?

The last key in the map that is strictly smaller than key. [...]

map<K2, V2>(MapEntry<K2, V2> transform(K key, V value)) → Map<K2, V2>

inherited

Returns a new map where all entries of this map are transformed by the given convert function.

noSuchMethod(Invocation invocation) → dynamic

inherited

Invoked when a non-existent method or property is accessed. [...]

putIfAbsent(K key, V ifAbsent()) → V

override

Look up the value of key, or add a new entry if it isn't there. [...]

remove(Object? key) → V?

override

Removes key and its associated value, if present, from the map. [...]

removeWhere(bool test(K key, V value)) → void

inherited

Removes all entries of this map that satisfy the given test.

toString() → String

inherited

A string representation of this object. [...]

update(K key, V update(V value), {V ifAbsent()}) → V

inherited

Updates the value for the provided key. [...]

updateAll(V update(K key, V value)) → void

inherited

Updates all values. [...]

Operators

operator ==(Object other) → bool

inherited

The equality operator. [...]

operator [](Object? key) → V?

override

The value for the given key, or null if key is not in the map. [...]

operator []=(K key, V value) → void

override

Associates the key with the given value. [...]