object Platform
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Will be removed in the future.
- Source
- Platform.scala
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- Platform
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- Any
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- Public
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Deprecated Type Members
- type ConcurrentModificationException = java.util.ConcurrentModificationException
This is a type alias for
java.util.ConcurrentModificationException
, which may be thrown by methods that detect an invalid modification of an object.This is a type alias for
java.util.ConcurrentModificationException
, which may be thrown by methods that detect an invalid modification of an object. For example, many common collection types do not allow modifying a collection while it is being iterated over.- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use
java.util.ConcurrentModificationException
instead.
- type StackOverflowError = java.lang.StackOverflowError
Thrown when a stack overflow occurs because a method or function recurses too deeply.
Thrown when a stack overflow occurs because a method or function recurses too deeply.
On the JVM, this is a type alias for
java.lang.StackOverflowError
, which itself extendsjava.lang.Error
. The same rules apply to catching ajava.lang.Error
as for Java, that it indicates a serious problem that a reasonable application should not try and catch.- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use
java.lang.StackOverflowError
instead.
Value Members
- final def !=(arg0: Any): Boolean
Test two objects for inequality.
Test two objects for inequality.
- returns
true
if !(this == that), false otherwise.
- Definition Classes
- AnyRef → Any
- final def ##: Int
Equivalent to
x.hashCode
except for boxed numeric types andnull
.Equivalent to
x.hashCode
except 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. Fornull
returns a hashcode wherenull.hashCode
throws aNullPointerException
.- returns
a hash value consistent with ==
- Definition Classes
- AnyRef → Any
- final def ==(arg0: Any): Boolean
The expression
x == that
is equivalent toif (x eq null) that eq null else x.equals(that)
.The expression
x == that
is equivalent toif (x eq null) that eq null else x.equals(that)
.- returns
true
if the receiver object is equivalent to the argument;false
otherwise.
- Definition Classes
- AnyRef → Any
- final def asInstanceOf[T0]: T0
Forces the compiler to treat the receiver object as having type
T0
, even though doing so may violate type safety.Forces the compiler to treat the receiver object as having type
T0
, even though doing so may violate type safety.This method is useful when you believe you have type information the compiler doesn't, and it also isn't possible to check the type at runtime. In such situations, skipping type safety is the only option.
It is platform dependent whether
asInstanceOf
has any effect at runtime. It might do a runtime type test on the erasure ofT0
, insert a conversion (such as boxing/unboxing), fill in a default value, or do nothing at all.In particular,
asInstanceOf
is not a type test. It does **not** mean:this match { case x: T0 => x case _ => throw ClassCastException("...")
Use pattern matching or isInstanceOf for type testing instead.
Situations where
asInstanceOf
is useful:- when flow analysis fails to deduce
T0
automatically - when down-casting a type parameter or an abstract type member (which cannot be checked at runtime due to type erasure) If there is any doubt and you are able to type test instead, you should do so.
Be careful of using
asInstanceOf
whenT0
is a primitive type. WhenT0
is primitive,asInstanceOf
may insert a conversion instead of a type test. If your intent is to convert, use atoT
method (x.toChar
,x.toByte
, etc.).- returns
the receiver object.
- Definition Classes
- Any
- Exceptions thrown
ClassCastException
if the receiver is not an instance of the erasure ofT0
, if that can be checked on this platform
- when flow analysis fails to deduce
- def clone(): AnyRef
Create a copy of the receiver object.
Create a copy of the receiver object.
The default implementation of the
clone
method is platform dependent.- returns
a copy of the receiver object.
- 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
eq
method implements an equivalence relation on non-null instances ofAnyRef
, and has three additional properties:- It is consistent: for any non-null instances
x
andy
of typeAnyRef
, multiple invocations ofx.eq(y)
consistently returnstrue
or consistently returnsfalse
. - For any non-null instance
x
of typeAnyRef
,x.eq(null)
andnull.eq(x)
returnsfalse
. null.eq(null)
returnstrue
.
When overriding the
equals
orhashCode
methods, 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
true
if the argument is a reference to the receiver object;false
otherwise.
- Definition Classes
- AnyRef
- It is consistent: for any non-null instances
- def equals(arg0: AnyRef): 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
finalize
method is invoked, as well as the interaction betweenfinalize
and 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
- final def getClass(): Class[_ <: AnyRef]
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 has the same erasure as
T0
.Test whether the dynamic type of the receiver object has the same erasure as
T0
.Depending on what
T0
is, the test is done in one of the below ways:T0
is a non-parameterized class type, e.g.BigDecimal
: this method returnstrue
if the value of the receiver object is aBigDecimal
or a subtype ofBigDecimal
.T0
is a parameterized class type, e.g.List[Int]
: this method returnstrue
if the value of the receiver object is someList[X]
for anyX
. For example,List(1, 2, 3).isInstanceOf[List[String]]
will return true.T0
is some singleton typex.type
or literalx
: this method returnsthis.eq(x)
. For example,x.isInstanceOf[1]
is equivalent tox.eq(1)
T0
is an intersectionX with Y
orX & Y: this method is equivalent to
x.isInstanceOf[X] && x.isInstanceOf[Y]T0
is a unionX | Y
: this method is equivalent tox.isInstanceOf[X] || x.isInstanceOf[Y]
T0
is a type parameter or an abstract type member: this method is equivalent toisInstanceOf[U]
whereU
isT0
's upper bound,Any
ifT0
is unbounded. For example,x.isInstanceOf[A]
whereA
is an unbounded type parameter will return true for any value ofx
.
This is exactly equivalent to the type pattern
_: T0
- returns
true
if the receiver object is an instance of erasure of typeT0
;false
otherwise.
- Definition Classes
- Any
- Note
due to the unexpectedness of
List(1, 2, 3).isInstanceOf[List[String]]
returning true andx.isInstanceOf[A]
whereA
is a type parameter or abstract member returning true, these forms issue a warning.
- final def ne(arg0: AnyRef): Boolean
Equivalent to
!(this eq that)
.Equivalent to
!(this eq that)
.- returns
true
if the argument is not a reference to the receiver object;false
otherwise.
- 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
- final def synchronized[T0](arg0: => T0): T0
Executes the code in
body
with an exclusive lock onthis
.Executes the code in
body
with an exclusive lock onthis
.- returns
the result of
body
- Definition Classes
- AnyRef
- 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
See https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#wait--.
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- Note
not specified by SLS as a member of AnyRef
- final def wait(arg0: Long, arg1: Int): Unit
See https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#wait-long-int-
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- Note
not specified by SLS as a member of AnyRef
- final def wait(arg0: Long): Unit
See https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#wait-long-.
Deprecated Value Members
- val EOL: String
The default line separator.
The default line separator.
On the JVM, this is equivalent to calling the method:
java.lang.System.lineSeparator
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use
java.lang.System#lineSeparator
instead.
- def arrayclear(arr: Array[Int]): Unit
Assigns the value of 0 to each element in the array.
Assigns the value of 0 to each element in the array.
- arr
A non-null Array[Int].
- Annotations
- @inline() @deprecated
- Deprecated
(Since version 2.13.0) Use
java.util.Arrays#fill
instead.- Exceptions thrown
java.lang.NullPointerException
Ifarr
isnull
.
- def arraycopy(src: AnyRef, srcPos: Int, dest: AnyRef, destPos: Int, length: Int): Unit
Copies
length
elements of arraysrc
starting at positionsrcPos
to the arraydest
starting at positiondestPos
.Copies
length
elements of arraysrc
starting at positionsrcPos
to the arraydest
starting at positiondestPos
. Ifsrc
==dest
, the copying will behave as if the elements copied fromsrc
were first copied to a temporary array before being copied back into the array at the destination positions.- src
A non-null array as source for the copy.
- srcPos
The starting index in the source array.
- dest
A non-null array as destination for the copy.
- destPos
The starting index in the destination array.
- length
The number of elements to be copied.
- Annotations
- @inline() @deprecated
- Deprecated
(Since version 2.13.0) Use
java.lang.System#arraycopy
instead.- Exceptions thrown
java.lang.ArrayStoreException
If eithersrc
ordest
are not of type [java.lang.Array]; or if the element type ofsrc
is not compatible with that ofdest
.java.lang.IndexOutOfBoundsException
If eithersrcPos
ordestPos
are outside of the bounds of their respective arrays; or iflength
is negative; or if there are less thanlength
elements available aftersrcPos
ordestPos
insrc
anddest
respectively.java.lang.NullPointerException
If eithersrc
ordest
arenull
.
- def collectGarbage(): Unit
Runs the garbage collector.
Runs the garbage collector.
This is a request that the underlying JVM runs the garbage collector. The results of this call depends heavily on the JVM used. The underlying JVM is free to ignore this request.
- Annotations
- @inline() @deprecated
- Deprecated
(Since version 2.13.0) Use
java.lang.System#gc
instead.
- def createArray(elemClass: Class[_], length: Int): AnyRef
Creates a new array of the specified type and given length.
Creates a new array of the specified type and given length.
Note that if
elemClass
is a subclass of scala.AnyVal then the returned value is an Array of the corresponding java primitive type. For example, the following codescala.compat.Platform.createArray(classOf[Int], 4)
returns an array of the java primitive typeint
.For a scala.AnyVal array, the values of the array are set to 0 for numeric value types (scala.Double, scala.Float, scala.Long, scala.Int, scala.Char, scala.Short, and scala.Byte), and
false
for scala.Boolean. Creation of an array of type scala.Unit is not possible.For subclasses of scala.AnyRef, the values of the array are set to
null
.The caller must cast the returned value to the correct type.
- elemClass
the
Class
object of the component type of the array- length
the length of the new array.
- returns
an array of the given component type as an
AnyRef
.
- Annotations
- @inline() @deprecated
- Deprecated
(Since version 2.13.0) Use
java.lang.reflect.Array#newInstance
instead.val a = scala.compat.Platform.createArray(classOf[Int], 4).asInstanceOf[Array[Int]] // returns Array[Int](0, 0, 0, 0)
- Exceptions thrown
java.lang.IllegalArgumentException
if componentType is scala.Unit orjava.lang.Void.TYPE
java.lang.NegativeArraySizeException
if the specified length is negativejava.lang.NullPointerException
IfelemClass
isnull
.
Example: - def currentTime: Long
The current time in milliseconds.
The current time in milliseconds. The time is counted since 1 January 1970 UTC.
Note that the operating system timer used to obtain this value may be less precise than a millisecond.
- Annotations
- @inline() @deprecated
- Deprecated
(Since version 2.13.0) Use
java.lang.System#currentTimeMillis
instead.
- def defaultCharsetName: String
The name of the default character set encoding as a string
The name of the default character set encoding as a string
- Annotations
- @inline() @deprecated
- Deprecated
(Since version 2.13.0) Use
java.nio.charset.Charset.defaultCharset#name
instead.
- def getClassForName(name: String): Class[_]
Returns the
Class
object associated with the class or interface with the given string name using the currentClassLoader
.Returns the
Class
object associated with the class or interface with the given string name using the currentClassLoader
. On the JVM, invoking this method is equivalent to:java.lang.Class.forName(name)
For more information, please see the Java documentation for java.lang.Class.
- name
the fully qualified name of the desired class.
- returns
the
Class
object for the class with the specified name.
- Annotations
- @inline() @deprecated
- Deprecated
(Since version 2.13.0) Use
java.lang.Class#forName
instead.val a = scala.compat.Platform.getClassForName("java.lang.Integer") // returns the Class[_] for java.lang.Integer
- Exceptions thrown
java.lang.ClassNotFoundException
if the class cannot be locatedjava.lang.ExceptionInInitializerError
if the initialization provoked by this method failsjava.lang.LinkageError
if the linkage fails
Example:
This is the documentation for the Scala standard library.
Package structure
The scala package contains core types like
Int
,Float
,Array
orOption
which are accessible in all Scala compilation units without explicit qualification or imports.Notable packages include:
scala.collection
and its sub-packages contain Scala's collections frameworkscala.collection.immutable
- Immutable, sequential data-structures such asVector
,List
,Range
,HashMap
orHashSet
scala.collection.mutable
- Mutable, sequential data-structures such asArrayBuffer
,StringBuilder
,HashMap
orHashSet
scala.collection.concurrent
- Mutable, concurrent data-structures such asTrieMap
scala.concurrent
- Primitives for concurrent programming such asFutures
andPromises
scala.io
- Input and output operationsscala.math
- Basic math functions and additional numeric types likeBigInt
andBigDecimal
scala.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.collection.parallel
- Parallel collections (scala-parallel-collections.jar)scala.util.parsing
- Parser combinators (scala-parser-combinators.jar)scala.swing
- A convenient wrapper around Java's GUI framework called Swing (scala-swing.jar)Automatic imports
Identifiers in the scala package and the
scala.Predef
object are always in scope by default.Some of these identifiers are type aliases provided as shortcuts to commonly used classes. For example,
List
is an alias forscala.collection.immutable.List
.Other aliases refer to classes provided by the underlying platform. For example, on the JVM,
String
is an alias forjava.lang.String
.