LinkedHashMap<K, V> class
Null safety
A hash-table based implementation of Map.
The insertion order of keys is remembered, and keys are iterated in the order they were inserted into the map. Values are iterated in their corresponding key's order. Changing a key's value, when the key is already in the map, does not change the iteration order, but removing the key and adding it again will make it be last in the iteration order.
The keys of a LinkedHashMap
must have consistent Object.==
and Object.hashCode implementations. This means that the ==
operator
must define a stable equivalence relation on the keys (reflexive,
symmetric, transitive, and consistent over time), and that hashCode
must be the same for objects that are considered equal by ==
.
- Implemented types
-
- Map<
K, V>
- Map<
Constructors
- LinkedHashMap({bool equals(K, K)?, int hashCode(K)?, bool isValidKey(dynamic)?})
-
Creates an insertion-ordered hash-table based Map. [...]
factory
- LinkedHashMap.from(Map other)
-
Creates a LinkedHashMap that contains all key value pairs of
other
. [...]factory -
LinkedHashMap.fromEntries(Iterable<
MapEntry< entries)K, V> > -
Creates a LinkedHashMap containing the entries of
entries
. [...]factory - LinkedHashMap.fromIterable(Iterable iterable, {K key(dynamic element)?, V value(dynamic element)?})
-
Creates a LinkedHashMap where the keys and values are computed from the
iterable
. [...]factory -
LinkedHashMap.fromIterables(Iterable<
K> keys, Iterable<V> values) -
Creates a LinkedHashMap associating the given
keys
tovalues
. [...]factory - LinkedHashMap.identity()
-
Creates an insertion-ordered identity-based map. [...]
factory
-
LinkedHashMap.of(Map<
K, V> other) -
Creates a LinkedHashMap that contains all key value pairs of
other
.factory
Properties
-
entries
→ Iterable<
MapEntry< K, V> > -
The map entries of this.
read-only, inherited
- hashCode → int
-
The hash code for this object. [...]
read-only, inherited
- isEmpty → bool
-
Whether there is no key/value pair in the map.
read-only, inherited
- isNotEmpty → bool
-
Whether there is at least one key/value pair in the map.
read-only, inherited
-
keys
→ Iterable<
K> -
The keys of this. [...]
read-only, inherited
- length → int
-
The number of key/value pairs in the map.
read-only, inherited
- runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited
-
values
→ Iterable<
V> -
The values of this. [...]
read-only, inherited
Methods
-
addAll(
Map< K, V> other) → void -
Adds all key/value pairs of
other
to this map. [...]inherited -
addEntries(
Iterable< MapEntry< newEntries) → voidK, V> > -
Adds all key/value pairs of
newEntries
to this map. [...]inherited -
cast<
RK, RV> () → Map< RK, RV> -
Provides a view of this map as having
RK
keys andRV
instances, if necessary. [...]inherited -
clear(
) → void -
Removes all entries from the map. [...]
inherited
-
containsKey(
Object? key) → bool -
Whether this map contains the given
key
. [...]inherited -
containsValue(
Object? value) → bool -
Whether this map contains the given
value
. [...]inherited -
forEach(
void action(K key, V value)) → void -
Applies
action
to each key/value pair of the map. [...]inherited -
map<
K2, V2> (MapEntry< K2, V2> convert(K key, V value)) → Map<K2, V2> -
Returns a new map where all entries of this map are transformed by
the given
convert
function.inherited -
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a non-existent 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. [...]inherited -
remove(
Object? key) → V? -
Removes
key
and its associated value, if present, from the map. [...]inherited -
removeWhere(
bool test(K key, V value)) → void -
Removes all entries of this map that satisfy the given
test
.inherited -
toString(
) → String -
A string representation of this object. [...]
inherited
-
update(
K key, V update(V value), {V ifAbsent()?}) → V -
Updates the value for the provided
key
. [...]inherited -
updateAll(
V update(K key, V value)) → void -
Updates all values. [...]
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator. [...]
inherited
-
operator [](
Object? key) → V? -
The value for the given
key
, ornull
ifkey
is not in the map. [...]inherited -
operator []=(
K key, V value) → void -
Associates the
key
with the givenvalue
. [...]inherited