const classafConcurrent::AtomicMap
sys::Obj afConcurrent::AtomicMap
A Map that provides fast reads and lightweight writes between threads. Use when reads far out number the writes.
The map is stored in an AtomicRef through which all reads are made. Writing makes a rw copy of the map and is thus a more expensive operation.
CAUTION: Write operations (
getOrAdd,set,remove&clear) are not synchronised. This makes them lightweight but also susceptible to data-loss during race conditions. This may be acceptable for caching situations where values is easily re-calculated.
Note that all objects held in the map must be immutable.
See From One Thread to Another... for more details.
- caseInsensitive
const Bool caseInsensitive := falseConfigures case sensitivity for maps with
Strkeys.AtomicMap() { it.keyType = Str#; it.caseInsensitive = true }- clear
This clear()Remove all key/value pairs from the map. Return this.
- containsKey
Returns
trueif the map contains the given key- def
const Obj? def := nullThe default value to use for get when a key isn't mapped.
- get
@Operator
Obj? get(Obj key, Obj? def := this.def)Returns the value associated with the given key. If key is not mapped, then return the value of the
defparameter. Ifdefis omitted it defaults tonull.- getOrAdd
Obj? getOrAdd(Obj key, |Obj->Obj? valFunc)Returns the value associated with the given key. If it doesn't exist then it is added from the value function.
This method is NOT thread safe. If two Actors call this method at the same time, the value function will be called twice for the same key.
- isEmpty
Bool isEmpty()Return
trueif size() == 0- keyType
const Type keyType := sys::Obj#Used to parameterize the backing map. Must be non-nullable.
AtomicMap() { it.keyType = Int# }- keys
Obj[] keys()Returns a list of all the mapped keys.
- map
Gets or sets a read-only copy of the backing map.
- ordered
const Bool ordered := falseIf
truethe map will maintain the order in which key/value pairs are added.AtomicMap() { it.ordered = true }- remove
Remove the key/value pair identified by the specified key from the map and return the value. If the key was not mapped then return
null.- rw
Get a read-write, mutable Map instance with the same contents.
- set
@Operator
Void set(Obj key, Obj? val)Sets the key / value pair.
- size
Int size()Get the number of key/value pairs in the map.
- valType
const Type valType := sys::Obj?#Used to parameterize the backing map.
AtomicMap() { it.valType = Int# }- vals
Obj?[] vals()Returns a list of all the mapped values.