class ParHashMap[K, +V] extends ParMap[K, V] with GenericParMapTemplate[K, V, ParHashMap] with ParMapLike[K, V, ParHashMap[K, V], HashMap[K, V]] with Serializable
Immutable parallel hash map, based on hash tries.
This is a base trait for Scala parallel collections. It defines behaviour
common to all parallel collections. Concrete parallel collections should
inherit this trait and ParIterable
if they want to define specific combiner
factories.
Parallel operations are implemented with divide and conquer style algorithms that parallelize well. The basic idea is to split the collection into smaller parts until they are small enough to be operated on sequentially.
All of the parallel operations are implemented as tasks within this trait. Tasks rely on the concept of splitters, which extend iterators. Every parallel collection defines:
def splitter: IterableSplitter[T]
which returns an instance of IterableSplitter[T]
, which is a subtype of Splitter[T]
.
Splitters have a method remaining
to check the remaining number of elements,
and method split
which is defined by splitters. Method split
divides the splitters
iterate over into disjunct subsets:
def split: Seq[Splitter]
which splits the splitter into a sequence of disjunct subsplitters. This is typically a very fast operation which simply creates wrappers around the receiver collection. This can be repeated recursively.
Tasks are scheduled for execution through a
scala.collection.parallel.TaskSupport object, which can be changed
through the tasksupport
setter of the collection.
Method newCombiner
produces a new combiner. Combiners are an extension of builders.
They provide a method combine
which combines two combiners and returns a combiner
containing elements of both combiners.
This method can be implemented by aggressively copying all the elements into the new combiner
or by lazily binding their results. It is recommended to avoid copying all of
the elements for performance reasons, although that cost might be negligible depending on
the use case. Standard parallel collection combiners avoid copying when merging results,
relying either on a two-step lazy construction or specific data-structure properties.
Methods:
def seq: Sequential def par: Repr
produce the sequential or parallel implementation of the collection, respectively.
Method par
just returns a reference to this parallel collection.
Method seq
is efficient - it will not copy the elements. Instead,
it will create a sequential version of the collection using the same underlying data structure.
Note that this is not the case for sequential collections in general - they may copy the elements
and produce a different underlying data structure.
The combination of methods toMap
, toSeq
or toSet
along with par
and seq
is a flexible
way to change between different collection types.
Since this trait extends the GenIterable
trait, methods like size
must also
be implemented in concrete collections, while iterator
forwards to splitter
by
default.
Each parallel collection is bound to a specific fork/join pool, on which dormant worker
threads are kept. The fork/join pool contains other information such as the parallelism
level, that is, the number of processors used. When a collection is created, it is assigned the
default fork/join pool found in the scala.parallel
package object.
Parallel collections are not necessarily ordered in terms of the foreach
operation (see Traversable
). Parallel sequences have a well defined order for iterators - creating
an iterator and traversing the elements linearly will always yield the same order.
However, bulk operations such as foreach
, map
or filter
always occur in undefined orders for all
parallel collections.
Existing parallel collection implementations provide strict parallel iterators. Strict parallel iterators are aware
of the number of elements they have yet to traverse. It's also possible to provide non-strict parallel iterators,
which do not know the number of elements remaining. To do this, the new collection implementation must override
isStrictSplitterCollection
to false
. This will make some operations unavailable.
To create a new parallel collection, extend the ParIterable
trait, and implement size
, splitter
,
newCombiner
and seq
. Having an implicit combiner factory requires extending this trait in addition, as
well as providing a companion object, as with regular collections.
Method size
is implemented as a constant time operation for parallel collections, and parallel collection
operations rely on this assumption.
The higher-order functions passed to certain operations may contain side-effects. Since implementations of bulk operations may not be sequential, this means that side-effects may not be predictable and may produce data-races, deadlocks or invalidation of state if care is not taken. It is up to the programmer to either avoid using side-effects or to use some form of synchronization when accessing mutable data.
- K
the key type of the map
- V
the value type of the map
- Self Type
- ParHashMap[K, V]
- Annotations
- @SerialVersionUID()
- Since
2.9
- See also
Scala's Parallel Collections Library overview section on Parallel Hash Tries for more information.
- Alphabetic
- By Inheritance
- ParHashMap
- Serializable
- Serializable
- ParMap
- ParIterable
- Immutable
- ParMap
- ParMapLike
- ParIterable
- ParIterableLike
- Parallel
- CustomParallelizable
- Parallelizable
- GenericParMapTemplate
- GenericParTemplate
- HasNewCombiner
- GenMap
- GenIterable
- GenTraversable
- GenericTraversableTemplate
- HasNewBuilder
- GenMapLike
- Equals
- GenIterableLike
- GenTraversableLike
- GenTraversableOnce
- AnyRef
- Any
- Hide All
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- Public
- All
Instance Constructors
- new ParHashMap()
Type Members
-
trait
Accessor
[R, Tp] extends StrictSplitterCheckTask[R, Tp]
Standard accessor task that iterates over the elements of the collection.
Standard accessor task that iterates over the elements of the collection.
- R
type of the result of this method (
R
for result).- Tp
the representation type of the task at hand.
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
class
Aggregate
[S] extends Accessor[S, Aggregate[S]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
trait
BuilderOps
[Elem, To] extends AnyRef
- Definition Classes
- ParIterableLike
-
class
Collect
[S, That] extends Transformer[Combiner[S, That], Collect[S, That]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
abstract
class
Composite
[FR, SR, R, First <: StrictSplitterCheckTask[FR, _], Second <: StrictSplitterCheckTask[SR, _]] extends NonDivisibleTask[R, Composite[FR, SR, R, First, Second]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Copy
[U >: T, That] extends Transformer[Combiner[U, That], Copy[U, That]]
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
class
CopyToArray
[U >: T, This >: Repr] extends Accessor[Unit, CopyToArray[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Count
extends Accessor[Int, Count]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
CreateScanTree
[U >: T] extends Transformer[ScanTree[U], CreateScanTree[U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Drop
[U >: T, This >: Repr] extends Transformer[Combiner[U, This], Drop[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Exists
extends Accessor[Boolean, Exists]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Filter
[U >: T, This >: Repr] extends Transformer[Combiner[U, This], Filter[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
FilterNot
[U >: T, This >: Repr] extends Transformer[Combiner[U, This], FilterNot[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Find
[U >: T] extends Accessor[Option[U], Find[U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
FlatMap
[S, That] extends Transformer[Combiner[S, That], FlatMap[S, That]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Fold
[U >: T] extends Accessor[U, Fold[U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Forall
extends Accessor[Boolean, Forall]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Foreach
[S] extends Accessor[Unit, Foreach[S]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
FromScanTree
[U >: T, That] extends StrictSplitterCheckTask[Combiner[U, That], FromScanTree[U, That]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
GroupBy
[K, U >: T] extends Transformer[HashMapCombiner[K, U], GroupBy[K, U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Map
[S, That] extends Transformer[Combiner[S, That], Map[S, That]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Max
[U >: T] extends Accessor[Option[U], Max[U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Min
[U >: T] extends Accessor[Option[U], Min[U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
trait
NonDivisible
[R] extends NonDivisibleTask[R, NonDivisible[R]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
trait
NonDivisibleTask
[R, Tp] extends StrictSplitterCheckTask[R, Tp]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
abstract
class
ParComposite
[FR, SR, R, First <: StrictSplitterCheckTask[FR, _], Second <: StrictSplitterCheckTask[SR, _]] extends Composite[FR, SR, R, First, Second]
Performs two tasks in parallel, and waits for both to finish.
Performs two tasks in parallel, and waits for both to finish.
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Partition
[U >: T, This >: Repr] extends Transformer[(Combiner[U, This], Combiner[U, This]), Partition[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Product
[U >: T] extends Accessor[U, Product[U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Reduce
[U >: T] extends Accessor[Option[U], Reduce[U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
abstract
class
ResultMapping
[R, Tp, R1] extends NonDivisibleTask[R1, ResultMapping[R, Tp, R1]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
case class
ScanLeaf
[U >: T](pit: IterableSplitter[U], op: (U, U) ⇒ U, from: Int, len: Int, prev: Option[ScanLeaf[U]], acc: U) extends ScanTree[U] with scala.Product with Serializable
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
case class
ScanNode
[U >: T](left: ScanTree[U], right: ScanTree[U]) extends ScanTree[U] with scala.Product with Serializable
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
trait
ScanTree
[U >: T] extends AnyRef
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
abstract
class
SeqComposite
[FR, SR, R, First <: StrictSplitterCheckTask[FR, _], Second <: StrictSplitterCheckTask[SR, _]] extends Composite[FR, SR, R, First, Second]
Sequentially performs one task after another.
Sequentially performs one task after another.
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
trait
SignallingOps
[PI <: DelegatedSignalling] extends AnyRef
- Definition Classes
- ParIterableLike
-
class
Slice
[U >: T, This >: Repr] extends Transformer[Combiner[U, This], Slice[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Span
[U >: T, This >: Repr] extends Transformer[(Combiner[U, This], Combiner[U, This]), Span[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
SplitAt
[U >: T, This >: Repr] extends Transformer[(Combiner[U, This], Combiner[U, This]), SplitAt[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
trait
StrictSplitterCheckTask
[R, Tp] extends Task[R, Tp]
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
class
Sum
[U >: T] extends Accessor[U, Sum[U]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
Take
[U >: T, This >: Repr] extends Transformer[Combiner[U, This], Take[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
TakeWhile
[U >: T, This >: Repr] extends Transformer[(Combiner[U, This], Boolean), TakeWhile[U, This]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
trait
TaskOps
[R, Tp] extends AnyRef
- Definition Classes
- ParIterableLike
-
class
ToParCollection
[U >: T, That] extends Transformer[Combiner[U, That], ToParCollection[U, That]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
ToParMap
[K, V, That] extends Transformer[Combiner[(K, V), That], ToParMap[K, V, That]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
trait
Transformer
[R, Tp] extends Accessor[R, Tp]
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
class
Zip
[U >: T, S, That] extends Transformer[Combiner[(U, S), That], Zip[U, S, That]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
ZipAll
[U >: T, S, That] extends Transformer[Combiner[(U, S), That], ZipAll[U, S, That]]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
class
DefaultKeySet
extends ParSet[K]
- Attributes
- protected
- Definition Classes
- ParMapLike
-
class
DefaultValuesIterable
extends ParIterable[V]
- Attributes
- protected
- Definition Classes
- ParMapLike
- class ParHashMapIterator extends IterableSplitter[(K, V)]
-
type
SSCTask[R, Tp] = StrictSplitterCheckTask[R, Tp]
- Definition Classes
- ParIterableLike
Value Members
-
final
def
!=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
-
final
def
##(): Int
- Definition Classes
- AnyRef → Any
-
def
+[U >: V](kv: (K, U)): ParHashMap[K, U]
- Definition Classes
- ParHashMap → ParMap → ParMap → GenMapLike
-
def
++[U >: (K, V), That](that: GenTraversableOnce[U])(implicit bf: CanBuildFrom[ParHashMap[K, V], U, That]): That
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
-(k: K): ParHashMap[K, V]
- Definition Classes
- ParHashMap → GenMapLike
-
def
/:[S](z: S)(op: (S, (K, V)) ⇒ S): S
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
:\[S](z: S)(op: ((K, V), S) ⇒ S): S
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
final
def
==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
-
def
aggregate[S](z: ⇒ S)(seqop: (S, (K, V)) ⇒ S, combop: (S, S) ⇒ S): S
Aggregates the results of applying an operator to subsequent elements.
Aggregates the results of applying an operator to subsequent elements.
This is a more general form of
fold
andreduce
. It has similar semantics, but does not require the result to be a supertype of the element type. It traverses the elements in different partitions sequentially, usingseqop
to update the result, and then appliescombop
to results from different partitions. The implementation of this operation may operate on an arbitrary number of collection partitions, socombop
may be invoked arbitrary number of times.For example, one might want to process some elements and then produce a
Set
. In this case,seqop
would process an element and append it to the set, whilecombop
would concatenate two sets from different partitions together. The initial valuez
would be an empty set.pc.aggregate(Set[Int]())(_ += process(_), _ ++ _)
Another example is calculating geometric mean from a collection of doubles (one would typically require big doubles for this).
- S
the type of accumulated results
- z
the initial value for the accumulated result of the partition - this will typically be the neutral element for the
seqop
operator (e.g.Nil
for list concatenation or0
for summation) and may be evaluated more than once- seqop
an operator used to accumulate results within a partition
- combop
an associative operator used to combine results from different partitions
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
apply(key: K): V
- Definition Classes
- ParMapLike → GenMapLike
-
final
def
asInstanceOf[T0]: T0
- Definition Classes
- Any
-
def
bf2seq[S, That](bf: CanBuildFrom[ParHashMap[K, V], S, That]): CanBuildFrom[HashMap[K, V], S, That]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
implicit
def
builder2ops[Elem, To](cb: Builder[Elem, To]): BuilderOps[Elem, To]
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
def
canEqual(other: Any): Boolean
- Definition Classes
- ParIterableLike
-
def
clone(): AnyRef
- Attributes
- protected[java.lang]
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
-
def
collect[S, That](pf: PartialFunction[(K, V), S])(implicit bf: CanBuildFrom[ParHashMap[K, V], S, That]): That
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
combinerFactory[S, That](cbf: () ⇒ Combiner[S, That]): CombinerFactory[S, That]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
def
combinerFactory: CombinerFactory[(K, V), ParHashMap[K, V]]
Creates a combiner factory.
Creates a combiner factory. Each combiner factory instance is used once per invocation of a parallel transformer method for a single collection.
The default combiner factory creates a new combiner every time it is requested, unless the combiner is thread-safe as indicated by its
canBeShared
method. In this case, the method returns a factory which returns the same combiner each time. This is typically done for concurrent parallel collections, the combiners of which allow thread safe access.- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
def
companion: GenericCompanion[ParIterable] with GenericParCompanion[ParIterable]
- Definition Classes
- ParIterable → ParIterable → GenericParTemplate → GenIterable → GenTraversable → GenericTraversableTemplate
-
def
contains(key: K): Boolean
- Definition Classes
- ParMapLike → GenMapLike
-
def
copyToArray[U >: (K, V)](xs: Array[U], start: Int, len: Int): Unit
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
copyToArray[U >: (K, V)](xs: Array[U], start: Int): Unit
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
copyToArray[U >: (K, V)](xs: Array[U]): Unit
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
count(p: ((K, V)) ⇒ Boolean): Int
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
debugBuffer: ArrayBuffer[String]
- Definition Classes
- ParIterableLike
-
def
default(key: K): V
- Definition Classes
- ParMapLike → GenMapLike
-
implicit
def
delegatedSignalling2ops[PI <: DelegatedSignalling](it: PI): SignallingOps[PI]
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
def
drop(n: Int): ParHashMap[K, V]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
dropWhile(pred: ((K, V)) ⇒ Boolean): ParHashMap[K, V]
Drops all elements in the longest prefix of elements that satisfy the predicate, and returns a collection composed of the remaining elements.
Drops all elements in the longest prefix of elements that satisfy the predicate, and returns a collection composed of the remaining elements.
This method will use
indexFlag
signalling capabilities. This means that splitters may set and read theindexFlag
state. The index flag is initially set to maximum integer value.- pred
the predicate used to test the elements
- returns
a collection composed of all the elements after the longest prefix of elements in this parallel iterable that satisfy the predicate
pred
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
empty: ParHashMap[K, V]
- Definition Classes
- ParHashMap → ParMap → ParMap → ParMapLike
-
final
def
eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
-
def
equals(that: Any): Boolean
- Definition Classes
- GenMapLike → Equals → AnyRef → Any
-
def
exists(p: ((K, V)) ⇒ Boolean): Boolean
Tests whether a predicate holds for some element of this parallel iterable.
Tests whether a predicate holds for some element of this parallel iterable.
This method will use
abort
signalling capabilities. This means that splitters may send and readabort
signals.- p
a predicate used to test elements
- returns
true if
p
holds for some element, false otherwise
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
filter(pred: ((K, V)) ⇒ Boolean): ParHashMap[K, V]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
filterKeys(p: (K) ⇒ Boolean): parallel.ParMap[K, V]
- Definition Classes
- ParMapLike → GenMapLike
-
def
filterNot(pred: ((K, V)) ⇒ Boolean): ParHashMap[K, V]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
finalize(): Unit
- Attributes
- protected[java.lang]
- Definition Classes
- AnyRef
- Annotations
- @throws( classOf[java.lang.Throwable] )
-
def
find(p: ((K, V)) ⇒ Boolean): Option[(K, V)]
Finds some element in the collection for which the predicate holds, if such an element exists.
Finds some element in the collection for which the predicate holds, if such an element exists. The element may not necessarily be the first such element in the iteration order.
If there are multiple elements obeying the predicate, the choice is nondeterministic.
This method will use
abort
signalling capabilities. This means that splitters may send and readabort
signals.- p
predicate used to test the elements
- returns
an option value with the element if such an element exists, or
None
otherwise
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
flatMap[S, That](f: ((K, V)) ⇒ GenTraversableOnce[S])(implicit bf: CanBuildFrom[ParHashMap[K, V], S, That]): That
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
flatten[B](implicit asTraversable: ((K, V)) ⇒ GenTraversableOnce[B]): ParIterable[B]
- Definition Classes
- GenericTraversableTemplate
-
def
fold[U >: (K, V)](z: U)(op: (U, U) ⇒ U): U
Folds the elements of this sequence using the specified associative binary operator.
Folds the elements of this sequence using the specified associative binary operator. The order in which the elements are reduced is unspecified and may be nondeterministic.
Note this method has a different signature than the
foldLeft
andfoldRight
methods of the traitTraversable
. The result of folding may only be a supertype of this parallel collection's type parameterT
.- U
a type parameter for the binary operator, a supertype of
T
.- z
a neutral element for the fold operation, it may be added to the result an arbitrary number of times, not changing the result (e.g.
Nil
for list concatenation, 0 for addition, or 1 for multiplication)- op
a binary operator that must be associative
- returns
the result of applying fold operator
op
between all the elements andz
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
foldLeft[S](z: S)(op: (S, (K, V)) ⇒ S): S
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
foldRight[S](z: S)(op: ((K, V), S) ⇒ S): S
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
forall(p: ((K, V)) ⇒ Boolean): Boolean
Tests whether a predicate holds for all elements of this parallel iterable.
Tests whether a predicate holds for all elements of this parallel iterable.
This method will use
abort
signalling capabilities. This means that splitters may send and readabort
signals.- p
a predicate used to test elements
- returns
true if
p
holds for all elements, false otherwise
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
foreach[U](f: ((K, V)) ⇒ U): Unit
Applies a function
f
to all the elements of parallel iterable in an undefined order.Applies a function
f
to all the elements of parallel iterable in an undefined order.- U
the result type of the function applied to each element, which is always discarded
- f
function applied to each element
- Definition Classes
- ParIterableLike → GenTraversableLike → GenTraversableOnce
-
def
genericBuilder[B]: Combiner[B, ParIterable[B]]
- Definition Classes
- GenericParTemplate → GenericTraversableTemplate
-
def
genericCombiner[B]: Combiner[B, ParIterable[B]]
- Definition Classes
- GenericParTemplate
-
def
genericMapCombiner[P, Q]: Combiner[(P, Q), ParHashMap[P, Q]]
- Definition Classes
- GenericParMapTemplate
-
def
get(k: K): Option[V]
- Definition Classes
- ParHashMap → GenMapLike
-
final
def
getClass(): Class[_]
- Definition Classes
- AnyRef → Any
-
def
getOrElse[U >: V](key: K, default: ⇒ U): U
- Definition Classes
- ParMapLike → GenMapLike
-
def
groupBy[K](f: ((K, V)) ⇒ K): ParMap[K, ParHashMap[K, V]]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
hasDefiniteSize: Boolean
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
hashCode(): Int
- Definition Classes
- GenMapLike → AnyRef → Any
-
def
head: (K, V)
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
headOption: Option[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
init: ParHashMap[K, V]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
initTaskSupport(): Unit
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
def
isDefinedAt(key: K): Boolean
- Definition Classes
- ParMapLike → GenMapLike
-
def
isEmpty: Boolean
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
final
def
isInstanceOf[T0]: Boolean
- Definition Classes
- Any
-
def
isStrictSplitterCollection: Boolean
Denotes whether this parallel collection has strict splitters.
Denotes whether this parallel collection has strict splitters.
This is true in general, and specific collection instances may choose to override this method. Such collections will fail to execute methods which rely on splitters being strict, i.e. returning a correct value in the
remaining
method.This method helps ensure that such failures occur on method invocations, rather than later on and in unpredictable ways.
- Definition Classes
- ParIterableLike
-
final
def
isTraversableAgain: Boolean
- Definition Classes
- ParIterableLike → GenTraversableLike → GenTraversableOnce
-
def
iterator: Splitter[(K, V)]
Creates a new split iterator used to traverse the elements of this collection.
Creates a new split iterator used to traverse the elements of this collection.
By default, this method is implemented in terms of the protected
splitter
method.- returns
a split iterator
- Definition Classes
- ParIterableLike → GenIterableLike
-
def
keySet: parallel.ParSet[K]
- Definition Classes
- ParMapLike → GenMapLike
-
def
keys: parallel.ParIterable[K]
- Definition Classes
- ParMapLike → GenMapLike
-
def
keysIterator: IterableSplitter[K]
- Definition Classes
- ParMapLike → GenMapLike
-
def
last: (K, V)
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
lastOption: Option[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
map[S, That](f: ((K, V)) ⇒ S)(implicit bf: CanBuildFrom[ParHashMap[K, V], S, That]): That
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
mapCompanion: GenericParMapCompanion[ParHashMap]
- Definition Classes
- ParHashMap → ParMap → ParMap → GenericParMapTemplate
-
def
mapValues[S](f: (V) ⇒ S): parallel.ParMap[K, S]
- Definition Classes
- ParMapLike → GenMapLike
-
def
max[U >: (K, V)](implicit ord: Ordering[U]): (K, V)
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
maxBy[S](f: ((K, V)) ⇒ S)(implicit cmp: Ordering[S]): (K, V)
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
min[U >: (K, V)](implicit ord: Ordering[U]): (K, V)
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
minBy[S](f: ((K, V)) ⇒ S)(implicit cmp: Ordering[S]): (K, V)
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
mkString: String
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
mkString(sep: String): String
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
mkString(start: String, sep: String, end: String): String
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
final
def
ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
-
def
newBuilder: Builder[(K, V), ParIterable[(K, V)]]
- Attributes
- protected[this]
- Definition Classes
- GenericParTemplate → GenericTraversableTemplate → HasNewBuilder
-
def
newCombiner: HashMapCombiner[K, V]
- Attributes
- protected[this]
- Definition Classes
- ParHashMap → GenericParMapTemplate → GenericParTemplate → HasNewCombiner
-
def
nonEmpty: Boolean
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
final
def
notify(): Unit
- Definition Classes
- AnyRef
-
final
def
notifyAll(): Unit
- Definition Classes
- AnyRef
-
def
par: ParHashMap[K, V]
Returns a parallel implementation of this collection.
Returns a parallel implementation of this collection.
For most collection types, this method creates a new parallel collection by copying all the elements. For these collection,
par
takes linear time. Mutable collections in this category do not produce a mutable parallel collection that has the same underlying dataset, so changes in one collection will not be reflected in the other one.Specific collections (e.g.
ParArray
ormutable.ParHashMap
) override this default behaviour by creating a parallel collection which shares the same underlying dataset. For these collections,par
takes constant or sublinear time.All parallel collections return a reference to themselves.
- returns
a parallel implementation of this collection
- Definition Classes
- ParIterableLike → CustomParallelizable → Parallelizable
-
def
parCombiner: Combiner[(K, V), ParHashMap[K, V]]
The default
par
implementation uses the combiner provided by this method to create a new parallel collection.The default
par
implementation uses the combiner provided by this method to create a new parallel collection.- returns
a combiner for the parallel collection of type
ParRepr
- Attributes
- protected[this]
- Definition Classes
- CustomParallelizable → Parallelizable
-
def
partition(pred: ((K, V)) ⇒ Boolean): (ParHashMap[K, V], ParHashMap[K, V])
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
product[U >: (K, V)](implicit num: Numeric[U]): U
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
reduce[U >: (K, V)](op: (U, U) ⇒ U): U
Reduces the elements of this sequence using the specified associative binary operator.
Reduces the elements of this sequence using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
Note this method has a different signature than the
reduceLeft
andreduceRight
methods of the traitTraversable
. The result of reducing may only be a supertype of this parallel collection's type parameterT
.- U
A type parameter for the binary operator, a supertype of
T
.- op
A binary operator that must be associative.
- returns
The result of applying reduce operator
op
between all the elements if the collection is nonempty.
- Definition Classes
- ParIterableLike → GenTraversableOnce
- Exceptions thrown
UnsupportedOperationException
if this parallel iterable is empty.
-
def
reduceLeft[U >: (K, V)](op: (U, (K, V)) ⇒ U): U
- Definition Classes
- ParIterableLike
-
def
reduceLeftOption[U >: (K, V)](op: (U, (K, V)) ⇒ U): Option[U]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
reduceOption[U >: (K, V)](op: (U, U) ⇒ U): Option[U]
Optionally reduces the elements of this sequence using the specified associative binary operator.
Optionally reduces the elements of this sequence using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
Note this method has a different signature than the
reduceLeftOption
andreduceRightOption
methods of the traitTraversable
. The result of reducing may only be a supertype of this parallel collection's type parameterT
.- U
A type parameter for the binary operator, a supertype of
T
.- op
A binary operator that must be associative.
- returns
An option value containing result of applying reduce operator
op
between all the elements if the collection is nonempty, andNone
otherwise.
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
reduceRight[U >: (K, V)](op: ((K, V), U) ⇒ U): U
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
reduceRightOption[U >: (K, V)](op: ((K, V), U) ⇒ U): Option[U]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
repr: ParHashMap[K, V]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
reuse[S, That](oldc: Option[Combiner[S, That]], newc: Combiner[S, That]): Combiner[S, That]
Optionally reuses an existing combiner for better performance.
Optionally reuses an existing combiner for better performance. By default it doesn't - subclasses may override this behaviour. The provided combiner
oldc
that can potentially be reused will be either some combiner from the previous computational task, orNone
if there was no previous phase (in which case this method must returnnewc
).- oldc
The combiner that is the result of the previous task, or
None
if there was no previous task.- newc
The new, empty combiner that can be used.
- returns
Either
newc
oroldc
.
- Attributes
- protected
- Definition Classes
- ParHashMap → ParIterableLike
-
def
sameElements[U >: (K, V)](that: GenIterable[U]): Boolean
- Definition Classes
- ParIterableLike → GenIterableLike
-
def
scan(z: (K, V))(op: ((K, V), (K, V)) ⇒ (K, V)): ParHashMap[(K, V)]
[use case] Computes a prefix scan of the elements of the collection.
[use case]Computes a prefix scan of the elements of the collection.
Note: The neutral element
z
may be applied more than once.- z
neutral element for the operator
op
- op
the associative operator for the scan
- returns
a new immutable parallel hash map containing the prefix scan of the elements in this immutable parallel hash map
- Definition Classes
- ParIterableLike → GenTraversableLike
Full Signaturedef scan[U >: (K, V), That](z: U)(op: (U, U) ⇒ U)(implicit bf: CanBuildFrom[ParHashMap[K, V], U, That]): That
-
def
scanBlockSize: Int
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
def
scanLeft[S, That](z: S)(op: (S, (K, V)) ⇒ S)(implicit bf: CanBuildFrom[ParHashMap[K, V], S, That]): That
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
scanRight[S, That](z: S)(op: ((K, V), S) ⇒ S)(implicit bf: CanBuildFrom[ParHashMap[K, V], S, That]): That
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
seq: HashMap[K, V]
- Definition Classes
- ParHashMap → ParIterableLike → Parallelizable → GenMap → GenIterable → GenTraversable → GenMapLike → GenTraversableOnce
-
def
sequentially[S, That <: Parallel](b: (HashMap[K, V]) ⇒ HashMap[K, V]): ParHashMap[K, V]
- Attributes
- protected[this]
- Definition Classes
- ParIterableLike
-
def
size: Int
- Definition Classes
- ParHashMap → GenTraversableLike → GenTraversableOnce
-
def
sizeHintIfCheap: Int
- Attributes
- protected[scala.collection]
- Definition Classes
- GenTraversableOnce
-
def
slice(unc_from: Int, unc_until: Int): ParHashMap[K, V]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
span(pred: ((K, V)) ⇒ Boolean): (ParHashMap[K, V], ParHashMap[K, V])
Splits this parallel iterable into a prefix/suffix pair according to a predicate.
Splits this parallel iterable into a prefix/suffix pair according to a predicate.
This method will use
indexFlag
signalling capabilities. This means that splitters may set and read theindexFlag
state. The index flag is initially set to maximum integer value.- pred
the predicate used to test the elements
- returns
a pair consisting of the longest prefix of the collection for which all the elements satisfy
pred
, and the rest of the collection
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
splitAt(n: Int): (ParHashMap[K, V], ParHashMap[K, V])
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
splitter: IterableSplitter[(K, V)]
Creates a new parallel iterator used to traverse the elements of this parallel collection.
Creates a new parallel iterator used to traverse the elements of this parallel collection. This iterator is more specific than the iterator of the returned by
iterator
, and augmented with additional accessor and transformer methods.- returns
a parallel iterator
- Definition Classes
- ParHashMap → ParIterableLike
-
def
stringPrefix: String
- Definition Classes
- ParMap → ParMap → ParIterable → GenTraversableLike
-
def
sum[U >: (K, V)](implicit num: Numeric[U]): U
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
final
def
synchronized[T0](arg0: ⇒ T0): T0
- Definition Classes
- AnyRef
-
def
tail: ParHashMap[K, V]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
take(n: Int): ParHashMap[K, V]
- Definition Classes
- ParIterableLike → GenTraversableLike
-
def
takeWhile(pred: ((K, V)) ⇒ Boolean): ParHashMap[K, V]
Takes the longest prefix of elements that satisfy the predicate.
Takes the longest prefix of elements that satisfy the predicate.
This method will use
indexFlag
signalling capabilities. This means that splitters may set and read theindexFlag
state. The index flag is initially set to maximum integer value.- pred
the predicate used to test the elements
- returns
the longest prefix of this parallel iterable of elements that satisfy the predicate
pred
- Definition Classes
- ParIterableLike → GenTraversableLike
-
implicit
def
task2ops[R, Tp](tsk: SSCTask[R, Tp]): TaskOps[R, Tp]
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
def
tasksupport: TaskSupport
The task support object which is responsible for scheduling and load-balancing tasks to processors.
The task support object which is responsible for scheduling and load-balancing tasks to processors.
- Definition Classes
- ParIterableLike
- See also
-
def
tasksupport_=(ts: TaskSupport): Unit
Changes the task support object which is responsible for scheduling and load-balancing tasks to processors.
Changes the task support object which is responsible for scheduling and load-balancing tasks to processors.
A task support object can be changed in a parallel collection after it has been created, but only during a quiescent period, i.e. while there are no concurrent invocations to parallel collection methods.
Here is a way to change the task support of a parallel collection:
import scala.collection.parallel._ val pc = mutable.ParArray(1, 2, 3) pc.tasksupport = new ForkJoinTaskSupport( new java.util.concurrent.ForkJoinPool(2))
- Definition Classes
- ParIterableLike
- See also
-
def
to[Col[_]](implicit cbf: CanBuildFrom[Nothing, (K, V), Col[(K, V)]]): Col[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toArray[U >: (K, V)](implicit arg0: ClassTag[U]): Array[U]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toBuffer[U >: (K, V)]: Buffer[U]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toIndexedSeq: immutable.IndexedSeq[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toIterable: ParIterable[(K, V)]
- Definition Classes
- ParIterable → ParIterableLike → GenTraversableOnce
-
def
toIterator: scala.Iterator[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toList: List[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toMap[P, Q](implicit ev: <:<[(K, V), (P, Q)]): ParMap[P, Q]
- Definition Classes
- ParMap → ParIterableLike → GenTraversableOnce
-
def
toParCollection[U >: (K, V), That](cbf: () ⇒ Combiner[U, That]): That
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
def
toParMap[K, V, That](cbf: () ⇒ Combiner[(K, V), That])(implicit ev: <:<[(K, V), (K, V)]): That
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
def
toSeq: ParSeq[(K, V)]
- Definition Classes
- ParIterable → ParIterableLike → GenTraversableOnce
-
def
toSet[U >: (K, V)]: ParSet[U]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toStream: Stream[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toString(): String
- Definition Classes
- ParIterableLike → AnyRef → Any
-
def
toTraversable: GenTraversable[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
toVector: Vector[(K, V)]
- Definition Classes
- ParIterableLike → GenTraversableOnce
-
def
transpose[B](implicit asTraversable: ((K, V)) ⇒ GenTraversableOnce[B]): ParIterable[ParIterable[B]]
- Definition Classes
- GenericTraversableTemplate
- Annotations
- @migration
- Migration
(Changed in version 2.9.0)
transpose
throws anIllegalArgumentException
if collections are not uniformly sized.
-
def
unzip[A1, A2](implicit asPair: ((K, V)) ⇒ (A1, A2)): (ParIterable[A1], ParIterable[A2])
- Definition Classes
- GenericTraversableTemplate
-
def
unzip3[A1, A2, A3](implicit asTriple: ((K, V)) ⇒ (A1, A2, A3)): (ParIterable[A1], ParIterable[A2], ParIterable[A3])
- Definition Classes
- GenericTraversableTemplate
- def updated[U >: V](key: K, value: U): ParMap[K, U]
-
def
values: parallel.ParIterable[V]
- Definition Classes
- ParMapLike → GenMapLike
-
def
valuesIterator: IterableSplitter[V]
- Definition Classes
- ParMapLike → GenMapLike
-
final
def
wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
-
final
def
wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
-
final
def
wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
-
def
withDefault[U >: V](d: (K) ⇒ U): ParMap[K, U]
The same map with a given default function.
The same map with a given default function. Note:
get
,contains
,iterator
,keys
, etc are not affected bywithDefault
.Invoking transformer methods (e.g.
map
) will not preserve the default value.- d
the function mapping keys to values, used for non-present keys
- returns
a wrapper of the map with a default value
- Definition Classes
- ParMap
-
def
withDefaultValue[U >: V](d: U): ParMap[K, U]
The same map with a given default value.
The same map with a given default value.
Invoking transformer methods (e.g.
map
) will not preserve the default value.- d
default value used for non-present keys
- returns
a wrapper of the map with a default value
- Definition Classes
- ParMap
-
def
withFilter(pred: ((K, V)) ⇒ Boolean): ParHashMap[K, V]
- Definition Classes
- ParIterableLike
-
def
wrap[R](body: ⇒ R): NonDivisible[R]
- Attributes
- protected
- Definition Classes
- ParIterableLike
-
def
zip[U >: (K, V), S, That](that: GenIterable[S])(implicit bf: CanBuildFrom[ParHashMap[K, V], (U, S), That]): That
- Definition Classes
- ParIterableLike → GenIterableLike
-
def
zipAll[S, U >: (K, V), That](that: GenIterable[S], thisElem: U, thatElem: S)(implicit bf: CanBuildFrom[ParHashMap[K, V], (U, S), That]): That
- Definition Classes
- ParIterableLike → GenIterableLike
-
def
zipWithIndex[U >: (K, V), That](implicit bf: CanBuildFrom[ParHashMap[K, V], (U, Int), That]): That
- Definition Classes
- ParIterableLike → GenIterableLike