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>
- Map<
- Implementers
Constructors
- MapBase()
-
const
Properties
-
entries
→ Iterable<
MapEntry< K, V> > -
The map entries of this Map.
no setteroverride
- hashCode → int
-
The hash code for this object.
no setterinherited
- isEmpty → bool
-
Whether there is no key/value pair in the map.
no setteroverride
- isNotEmpty → bool
-
Whether there is at least one key/value pair in the map.
no setteroverride
-
keys
→ Iterable<
K> -
The keys of this Map.
no setteroverride
- length → int
-
The number of key/value pairs in the map.
no setteroverride
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
-
values
→ Iterable<
V> -
The values of this Map.
no setteroverride
Methods
-
addAll(
Map< K, V> other) → void -
Adds all key/value pairs of
otherto this map.override -
addEntries(
Iterable< MapEntry< newEntries) → voidK, V> > -
Adds all key/value pairs of
newEntriesto this map.override -
cast<
RK, RV> () → Map< RK, RV> -
Provides a view of this map as having
RKkeys andRVinstances, 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
actionto 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
convertfunction.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
keyand 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, ornullifkeyis not in the map.override -
operator []=(
K key, V value) → void -
Associates the
keywith the givenvalue.override
Static Methods
-
mapToString(
Map< Object?, Object?> m) → String