dart:collection

SplayTreeMap 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 [], 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.

Implements

• Map<K, V>

Constructors

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

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

factory

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

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

factory

Creates a SplayTreeMap associating the given keys to values.

Properties

isEmpty → bool

read-only

isNotEmpty → bool

read-only

keys → Iterable<K>

read-only

length → int

read-only

values → Iterable<V>

read-only

hashCode → int

read-only, inherited

The hash code for this object.

runtimeType → Type

read-only, inherited

A representation of the runtime type of the object.

Operators

operator [](Object key) → V

Returns the value for the given key or null if key is not in the map.

operator []=(K key, V value) → void

Associates the key with the given value.

operator ==(other) → bool

inherited

The equality operator.

Methods

addAll(Map<K, V> other) → void

Adds all key-value pairs of other to this map.

clear() → void

Removes all pairs from the map.

containsKey(Object key) → bool

Returns true if this map contains the given key.

containsValue(Object value) → bool

Returns true if this map contains the given value.

firstKey() → K

Get the first key in the map. Returns null if the map is empty.

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

Applies f to each key-value pair of the map.

lastKey() → K

Get the last key in the map. Returns null if the map is empty.

lastKeyBefore(K key) → K

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

putIfAbsent(K key, V ifAbsent()) → V

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

remove(Object key) → V

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

toString() → String

Returns a string representation of this object.

noSuchMethod(Invocation invocation) → dynamic

inherited

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