description

# MapBase<K, V> class abstract mixin

Base class for implementing a Map.

This class has a basic implementation of all but five of the members of Map. A basic `Map` class can be implemented by extending this class and implementing `keys`, `operator[]`, `operator[]=`, `remove` and `clear`. The remaining operations are implemented in terms of these five.

The `keys` iterable should have efficient Iterable.length and Iterable.contains operations, and it should catch concurrent modifications of the keys while iterating.

A more efficient implementation is usually possible by overriding some of the other members as well.

Implemented types
  - Map<K, V>
Implementers
  - AudioParamMap
  - MidiInputMap
  - MidiOutputMap
  - RtcStatsReport
  - SplayTreeMap
  - Storage
  - UnmodifiableMapBase

## Constructors

MapBase()
  const

## Properties

entries → Iterable<MapEntry<K, V>>
  The map entries of this Map.
  no setter override
hashCode → int
  The hash code for this object.
  no setter inherited
isEmpty → bool
  Whether there is no key/value pair in the map.
  no setter override
isNotEmpty → bool
  Whether there is at least one key/value pair in the map.
  no setter override
keys → Iterable<K>
  The keys of this Map.
  no setter override
length → int
  The number of key/value pairs in the map.
  no setter override
runtimeType → Type
  A representation of the runtime type of the object.
  no setter inherited
values → Iterable<V>
  The values of this Map.
  no setter override

## Methods

addAll(Map<K, V> other) → void
  Adds all key/value pairs of `other` to this map.
  override
addEntries(Iterable<MapEntry<K, V>> newEntries) → void
  Adds all key/value pairs of `newEntries` to this map.
  override
cast<RK, RV>() → Map<RK, RV>
  Provides a view of this map as having `RK` keys and `RV` instances, if necessary.
  override
clear() → void
  Removes all entries from the map.
  override
containsKey(Object? key) → bool
  Whether this map contains the given `key`.
  override
containsValue(Object? value) → bool
  Whether this map contains the given `value`.
  override
forEach(void action(K key, V value)) → void
  Applies `action` to each key/value pair of the map.
  override
map<K2, V2>(MapEntry<K2, V2> transform(K key, V value)) → Map<K2, V2>
  Returns a new map where all entries of this map are transformed by the given `convert` function.
  override
noSuchMethod(Invocation invocation) → dynamic
  Invoked when a nonexistent method or property is accessed.
  inherited
putIfAbsent(K key, V ifAbsent()) → V
  Look up the value of `key`, or add a new entry if it isn't there.
  override
remove(Object? key) → V?
  Removes `key` and its associated value, if present, from the map.
  override
removeWhere(bool test(K key, V value)) → void
  Removes all entries of this map that satisfy the given `test`.
  override
toString() → String
  A string representation of this object.
  override
update(K key, V update(V value), {V ifAbsent()?}) → V
  Updates the value for the provided `key`.
  override
updateAll(V update(K key, V value)) → void
  Updates all values.
  override

## Operators

operator ==(Object other) → bool
  The equality operator.
  inherited
operator [](Object? key) → V?
  The value for the given `key`, or `null` if `key` is not in the map.
  override
operator []=(K key, V value) → void
  Associates the `key` with the given `value`.
  override

## Static Methods

mapToString(Map<Object?, Object?> m) → String