UnmodifiableMapFromIMap<K, V> class
The UnmodifiableMapFromIMap is a relatively safe, unmodifiable Map that is built from an IMap or another Map. The construction of the UnmodifiableMapFromIMap is very fast, since it makes no copies of the given map items, but just uses it directly.
If you try to use methods that modify the UnmodifiableMapFromIMap, like add, it will throw an UnsupportedError.
If you create it from an IMap, it is also very fast to lock the UnmodifiableMapFromIMap back into an IMap.
How does it compare to Dart's native Map.unmodifiable and UnmodifiableMapView?
Map.unmodifiable is slow, but it's always safe, because it is not a view, and actually creates a new map. On the other hand, UnmodifiableMapFromIMap and UnmodifiableMapView are fast, but if you create them from a regular Map and then modify that original Map, you will also be modifying the views. Also note, if you create an UnmodifiableMapFromIMap from an IMap, then it's totally safe , then it's totally safe because the original IMap can't be modified.
The only different between an UnmodifiableMapFromIMap and an UnmodifiableMapView is that UnmodifiableMapFromIMap accepts both a Map and an IMap.
See also: ModifiableMapFromIMap
- Implemented types
-
- Map<
K, V> - CanBeEmpty
- Map<
- Mixed in types
-
- MapMixin<
K, V>
- MapMixin<
- Available Extensions
- Annotations
Constructors
-
UnmodifiableMapFromIMap(IMap<
K, V> imap) -
Create an unmodifiable Set view of type UnmodifiableSetView, from an
iset
. -
UnmodifiableMapFromIMap.fromMap(Map<
K, V> map) - Create an unmodifiable Set view of type UnmodifiableSetView, from another Set.
Properties
-
entries
→ Iterable<
MapEntry< K, V> > -
The map entries of this.
no setterinherited
- hashCode → int
-
The hash code for this object.
no setterinherited
- isEmpty → bool
-
Whether there is no key/value pair in the map.
no setterinherited
- isNotEmpty → bool
-
Whether there is at least one key/value pair in the map.
no setterinherited
-
keys
→ Iterable<
K> -
The keys of this.
no setteroverride
- length → int
-
The number of key/value pairs in the map.
no setterinherited
-
lock
→ IMap<
K, V> -
no setter
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
-
values
→ Iterable<
V> -
The values of this.
no setterinherited
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.
override
-
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> 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.inherited -
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.inherited -
remove(
covariant K 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
.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 [](
covariant K key) → V? -
The value for the given
key
, ornull
ifkey
is not in the map.override -
operator []=(
K key, V value) → void -
Associates the
key
with the givenvalue
.override