class MapBuilder[A, B, Coll <: GenMap[A, B] with GenMapLike[A, B, Coll]] extends ReusableBuilder[(A, B), Coll]
The canonical builder for immutable maps, working with the map's + method
to add new elements.
Collections are built from their empty element using this + method.
- A
Type of the keys for the map this builder creates.
- B
Type of the values for the map this builder creates.
- Coll
The type of the actual collection this builder builds.
- Source
- MapBuilder.scala
- Since
2.8
- Alphabetic
- By Inheritance
- MapBuilder
- ReusableBuilder
- Builder
- Growable
- Clearable
- AnyRef
- Any
- by CollectionsHaveToParArray
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
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- Public
- All
Instance Constructors
-
new
MapBuilder(empty: Coll)
- empty
The empty element of the collection.
Value Members
-
final
def
!=(arg0: Any): Boolean
Test two objects for inequality.
Test two objects for inequality.
- returns
trueif !(this == that), false otherwise.
- Definition Classes
- AnyRef → Any
-
final
def
##(): Int
Equivalent to
x.hashCodeexcept for boxed numeric types andnull.Equivalent to
x.hashCodeexcept for boxed numeric types andnull. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. Fornullreturns a hashcode wherenull.hashCodethrows aNullPointerException.- returns
a hash value consistent with ==
- Definition Classes
- AnyRef → Any
-
def
+(other: String): String
- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to any2stringadd[MapBuilder[A, B, Coll]] performed by method any2stringadd in scala.Predef.
- Definition Classes
- any2stringadd
-
def
++=(xs: TraversableOnce[(A, B)]): MapBuilder.this.type
adds all elements produced by a TraversableOnce to this growable collection.
adds all elements produced by a TraversableOnce to this growable collection.
- xs
the TraversableOnce producing the elements to add.
- returns
the growable collection itself.
- Definition Classes
- Growable
-
def
+=(x: (A, B)): MapBuilder.this.type
Adds a single element to the builder.
Adds a single element to the builder.
- returns
the builder itself.
- Definition Classes
- MapBuilder → Builder → Growable
-
def
+=(elem1: (A, B), elem2: (A, B), elems: (A, B)*): MapBuilder.this.type
adds two or more elements to this growable collection.
adds two or more elements to this growable collection.
- elem1
the first element to add.
- elem2
the second element to add.
- elems
the remaining elements to add.
- returns
the growable collection itself
- Definition Classes
- Growable
-
def
->[B](y: B): (MapBuilder[A, B, Coll], B)
- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to ArrowAssoc[MapBuilder[A, B, Coll]] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @inline()
-
final
def
==(arg0: Any): Boolean
The expression
x == thatis equivalent toif (x eq null) that eq null else x.equals(that).The expression
x == thatis equivalent toif (x eq null) that eq null else x.equals(that).- returns
trueif the receiver object is equivalent to the argument;falseotherwise.
- Definition Classes
- AnyRef → Any
-
final
def
asInstanceOf[T0]: T0
Cast the receiver object to be of type
T0.Cast the receiver object to be of type
T0.Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression
1.asInstanceOf[String]will throw aClassCastExceptionat runtime, while the expressionList(1).asInstanceOf[List[String]]will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.- returns
the receiver object.
- Definition Classes
- Any
- Exceptions thrown
ClassCastExceptionif the receiver object is not an instance of the erasure of typeT0.
-
def
clear(): Unit
Clears the contents of this builder.
Clears the contents of this builder. After execution of this method, the builder will contain no elements.
If executed immediately after a call to
result, this allows a new instance of the same type of collection to be built.- Definition Classes
- MapBuilder → ReusableBuilder → Builder → Growable → Clearable
-
def
clone(): AnyRef
Create a copy of the receiver object.
-
var
elems: Coll
- Attributes
- protected
-
def
ensuring(cond: (MapBuilder[A, B, Coll]) ⇒ Boolean, msg: ⇒ Any): MapBuilder[A, B, Coll]
- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to Ensuring[MapBuilder[A, B, Coll]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
-
def
ensuring(cond: (MapBuilder[A, B, Coll]) ⇒ Boolean): MapBuilder[A, B, Coll]
- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to Ensuring[MapBuilder[A, B, Coll]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
-
def
ensuring(cond: Boolean, msg: ⇒ Any): MapBuilder[A, B, Coll]
- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to Ensuring[MapBuilder[A, B, Coll]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
-
def
ensuring(cond: Boolean): MapBuilder[A, B, Coll]
- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to Ensuring[MapBuilder[A, B, Coll]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
-
final
def
eq(arg0: AnyRef): Boolean
Tests whether the argument (
that) is a reference to the receiver object (this).Tests whether the argument (
that) is a reference to the receiver object (this).The
eqmethod implements an equivalence relation on non-null instances ofAnyRef, and has three additional properties:- It is consistent: for any non-null instances
xandyof typeAnyRef, multiple invocations ofx.eq(y)consistently returnstrueor consistently returnsfalse. - For any non-null instance
xof typeAnyRef,x.eq(null)andnull.eq(x)returnsfalse. null.eq(null)returnstrue.
When overriding the
equalsorhashCodemethods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2), they should be equal to each other (o1 == o2) and they should hash to the same value (o1.hashCode == o2.hashCode).- returns
trueif the argument is a reference to the receiver object;falseotherwise.
- Definition Classes
- AnyRef
- It is consistent: for any non-null instances
-
def
equals(arg0: Any): Boolean
The equality method for reference types.
-
def
finalize(): Unit
Called by the garbage collector on the receiver object when there are no more references to the object.
Called by the garbage collector on the receiver object when there are no more references to the object.
The details of when and if the
finalizemethod is invoked, as well as the interaction betweenfinalizeand non-local returns and exceptions, are all platform dependent.- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws( classOf[java.lang.Throwable] )
- Note
not specified by SLS as a member of AnyRef
-
def
formatted(fmtstr: String): String
Returns string formatted according to given
formatstring.Returns string formatted according to given
formatstring. Format strings are as forString.format(@see java.lang.String.format).- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to StringFormat[MapBuilder[A, B, Coll]] performed by method StringFormat in scala.Predef.
- Definition Classes
- StringFormat
- Annotations
- @inline()
-
final
def
getClass(): Class[_]
Returns the runtime class representation of the object.
-
def
hashCode(): Int
The hashCode method for reference types.
-
final
def
isInstanceOf[T0]: Boolean
Test whether the dynamic type of the receiver object is
T0.Test whether the dynamic type of the receiver object is
T0.Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression
1.isInstanceOf[String]will returnfalse, while the expressionList(1).isInstanceOf[List[String]]will returntrue. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.- returns
trueif the receiver object is an instance of erasure of typeT0;falseotherwise.
- Definition Classes
- Any
-
def
mapResult[NewTo](f: (Coll) ⇒ NewTo): Builder[(A, B), NewTo]
Creates a new builder by applying a transformation function to the results of this builder.
Creates a new builder by applying a transformation function to the results of this builder.
- NewTo
the type of collection returned by
f.- f
the transformation function.
- returns
a new builder which is the same as the current builder except that a transformation function is applied to this builder's result.
- Definition Classes
- Builder
- Note
The original builder should no longer be used after
mapResultis called.
-
final
def
ne(arg0: AnyRef): Boolean
Equivalent to
!(this eq that).Equivalent to
!(this eq that).- returns
trueif the argument is not a reference to the receiver object;falseotherwise.
- Definition Classes
- AnyRef
-
final
def
notify(): Unit
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up a single thread that is waiting on the receiver object's monitor.
- Definition Classes
- AnyRef
- Annotations
- @native()
- Note
not specified by SLS as a member of AnyRef
-
final
def
notifyAll(): Unit
Wakes up all threads that are waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
- Definition Classes
- AnyRef
- Annotations
- @native()
- Note
not specified by SLS as a member of AnyRef
-
def
result(): Coll
Produces a collection from the added elements.
Produces a collection from the added elements.
After a call to
result, the behavior of all other methods is undefined save forclear. Ifclearis called, then the builder is reset and may be used to build another instance.- returns
a collection containing the elements added to this builder.
- Definition Classes
- MapBuilder → ReusableBuilder → Builder
-
def
sizeHint(coll: TraversableLike[_, _], delta: Int): Unit
Gives a hint that one expects the
resultof this builder to have the same size as the given collection, plus some delta.Gives a hint that one expects the
resultof this builder to have the same size as the given collection, plus some delta. This will provide a hint only if the collection is known to have a cheapsizemethod. Currently this is assumed to be the case if and only if the collection is of typeIndexedSeqLike. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.- coll
the collection which serves as a hint for the result's size.
- delta
a correction to add to the
coll.sizeto produce the size hint.
- Definition Classes
- Builder
-
def
sizeHint(coll: TraversableLike[_, _]): Unit
Gives a hint that one expects the
resultof this builder to have the same size as the given collection, plus some delta.Gives a hint that one expects the
resultof this builder to have the same size as the given collection, plus some delta. This will provide a hint only if the collection is known to have a cheapsizemethod, which is determined by callingsizeHint.Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.
- coll
the collection which serves as a hint for the result's size.
- Definition Classes
- Builder
-
def
sizeHint(size: Int): Unit
Gives a hint how many elements are expected to be added when the next
resultis called.Gives a hint how many elements are expected to be added when the next
resultis called. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.- size
the hint how many elements will be added.
- Definition Classes
- Builder
-
def
sizeHintBounded(size: Int, boundingColl: TraversableLike[_, _]): Unit
Gives a hint how many elements are expected to be added when the next
resultis called, together with an upper bound given by the size of some other collection.Gives a hint how many elements are expected to be added when the next
resultis called, together with an upper bound given by the size of some other collection. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.- size
the hint how many elements will be added.
- boundingColl
the bounding collection. If it is an IndexedSeqLike, then sizes larger than collection's size are reduced.
- Definition Classes
- Builder
-
final
def
synchronized[T0](arg0: ⇒ T0): T0
- Definition Classes
- AnyRef
-
def
toParArray: ParArray[T]
- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to CollectionsHaveToParArray[MapBuilder[A, B, Coll], T] performed by method CollectionsHaveToParArray in scala.collection.parallel. This conversion will take place only if an implicit value of type (MapBuilder[A, B, Coll]) ⇒ GenTraversableOnce[T] is in scope.
- Definition Classes
- CollectionsHaveToParArray
-
def
toString(): String
Creates a String representation of this object.
Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.
- returns
a String representation of the object.
- Definition Classes
- AnyRef → Any
-
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
-
def
→[B](y: B): (MapBuilder[A, B, Coll], B)
- Implicit
- This member is added by an implicit conversion from MapBuilder[A, B, Coll] to ArrowAssoc[MapBuilder[A, B, Coll]] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
This is the documentation for the Scala standard library.
Package structure
The scala package contains core types like
Int,Float,ArrayorOptionwhich are accessible in all Scala compilation units without explicit qualification or imports.Notable packages include:
scala.collectionand its sub-packages contain Scala's collections frameworkscala.collection.immutable- Immutable, sequential data-structures such asVector,List,Range,HashMaporHashSetscala.collection.mutable- Mutable, sequential data-structures such asArrayBuffer,StringBuilder,HashMaporHashSetscala.collection.concurrent- Mutable, concurrent data-structures such asTrieMapscala.collection.parallel.immutable- Immutable, parallel data-structures such asParVector,ParRange,ParHashMaporParHashSetscala.collection.parallel.mutable- Mutable, parallel data-structures such asParArray,ParHashMap,ParTrieMaporParHashSetscala.concurrent- Primitives for concurrent programming such asFuturesandPromisesscala.io- Input and output operationsscala.math- Basic math functions and additional numeric types likeBigIntandBigDecimalscala.sys- Interaction with other processes and the operating systemscala.util.matching- Regular expressionsOther packages exist. See the complete list on the right.
Additional parts of the standard library are shipped as separate libraries. These include:
scala.reflect- Scala's reflection API (scala-reflect.jar)scala.xml- XML parsing, manipulation, and serialization (scala-xml.jar)scala.swing- A convenient wrapper around Java's GUI framework called Swing (scala-swing.jar)scala.util.parsing- Parser combinators (scala-parser-combinators.jar)Automatic imports
Identifiers in the scala package and the
scala.Predefobject are always in scope by default.Some of these identifiers are type aliases provided as shortcuts to commonly used classes. For example,
Listis an alias forscala.collection.immutable.List.Other aliases refer to classes provided by the underlying platform. For example, on the JVM,
Stringis an alias forjava.lang.String.