Class scala.Enumeration
abstract class Enumeration extends Serializable
Instance Constructors
new Enumeration()
new Enumeration(initial: Int)
- initial
The initial value from which to count the integers that identifies values at run-time.
Type Members
class Val extends Value with Serializable
A class implementing the scala.Enumeration.Value type. This class can be overridden to change the enumeration's naming and integer identification behaviour.
- Attributes
- protected
- Annotations
- @SerialVersionUID()
abstract class Value extends Ordered[Value] with Serializable
The type of the enumerated values.
- Annotations
- @SerialVersionUID()
class ValueSet extends AbstractSet[Value] with SortedSet[Value] with SortedSetOps[Value, SortedSet, ValueSet] with StrictOptimizedIterableOps[Value, Set, ValueSet] with Serializable
A class for sets of values. Iterating through this set will yield values in increasing order of their ids.
Value Members
final def !=(arg0: Any): Boolean
Test two objects for inequality.
- returns
trueif !(this == that), false otherwise.
- Definition Classes
- AnyRef → Any
final def ##(): Int
Equivalent to x.hashCode except for boxed numeric types and null. 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. For null returns a hashcode where null.hashCode throws a NullPointerException.
- returns
a hash value consistent with ==
- Definition Classes
- AnyRef → Any
def +(other: String): String
- Implicit
- This member is added by an implicit conversion from Enumeration toany2stringadd[Enumeration] performed by method any2stringadd in scala.Predef.
- Definition Classes
- any2stringadd
def ->[B](y: B): (Enumeration, B)
- Implicit
- This member is added by an implicit conversion from Enumeration toArrowAssoc[Enumeration] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @inline()
final def ==(arg0: Any): Boolean
The expression x == that is equivalent to if (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 Value(i: Int, name: String): Value
Creates a fresh value, part of this enumeration, called name and identified by the integer i.
- i
An integer that identifies this value at run-time. It must be unique amongst all values of the enumeration.
- name
A human-readable name for that value.
- returns
Fresh value with the provided identifier
iand namename.
- Attributes
- protected
final def Value(name: String): Value
Creates a fresh value, part of this enumeration, called name.
- name
A human-readable name for that value.
- returns
Fresh value called
name.
- Attributes
- protected
final def Value(i: Int): Value
Creates a fresh value, part of this enumeration, identified by the integer i.
- i
An integer that identifies this value at run-time. It must be unique amongst all values of the enumeration.
- returns
Fresh value identified by
i.
- Attributes
- protected
final def Value: Value
Creates a fresh value, part of this enumeration.
- Attributes
- protected
final def apply(x: Int): Value
final def asInstanceOf[T0]: 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 a ClassCastException at runtime, while the expression List(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 clone(): AnyRef
Create a copy of the receiver object.
The default implementation of the clone method is platform dependent.
- returns
a copy of the receiver object.
def ensuring(cond: (Enumeration) => Boolean, msg: => Any): Enumeration
- Implicit
- This member is added by an implicit conversion from Enumeration toEnsuring[Enumeration] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
def ensuring(cond: (Enumeration) => Boolean): Enumeration
- Implicit
- This member is added by an implicit conversion from Enumeration toEnsuring[Enumeration] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
def ensuring(cond: Boolean, msg: => Any): Enumeration
- Implicit
- This member is added by an implicit conversion from Enumeration toEnsuring[Enumeration] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
def ensuring(cond: Boolean): Enumeration
- Implicit
- This member is added by an implicit conversion from Enumeration toEnsuring[Enumeration] 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).
The eq method implements an equivalence relation on non-null instances of AnyRef, and has three additional properties:
-
It is consistent: for any non-null instances
x and y of type AnyRef, multiple invocations of x.eq(y) consistently returns true or consistently returns false.For any non-null instance x of type AnyRef, x.eq(null) and null.eq(x) returns false.
null.eq(null) returns true. When overriding the equals or hashCode 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
trueif the argument is a reference to the receiver object;falseotherwise.
- Definition Classes
- AnyRef
def equals(arg0: AnyRef): Boolean
The equality method for reference types. Default implementation delegates to eq.
See also equals in scala.Any.
- returns
trueif the receiver object is equivalent to the argument;falseotherwise.
- Definition Classes
- AnyRef → Any
def finalize(): Unit
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 between finalize and non-local returns and exceptions, are all platform dependent.
def formatted(fmtstr: String): String
Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format).
- Implicit
- This member is added by an implicit conversion from Enumeration toStringFormat[Enumeration] performed by method StringFormat in scala.Predef.
- Definition Classes
- StringFormat
- Annotations
- @inline()
final def getClass(): Class[_ <: AnyRef]
Returns the runtime class representation of the object.
- returns
a class object corresponding to the runtime type of the receiver.
def hashCode(): Int
The hashCode method for reference types. See hashCode in scala.Any.
- returns
the hash code value for this object.
final def isInstanceOf[T0]: Boolean
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 return false, while the expression List(1).isInstanceOf[List[String]] will return true. 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
final def maxId: Int
final def ne(arg0: AnyRef): Boolean
Equivalent to !(this eq that).
- returns
trueif the argument is not a reference to the receiver object;falseotherwise.
- Definition Classes
- AnyRef
var nextId: Int
The integer to use to identify the next created value.
- Attributes
- protected
var nextName: Iterator[String]
The string to use to name the next created value.
- Attributes
- protected
final def notify(): Unit
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.
- Definition Classes
- AnyRef
- Annotations
- @native()
- Note
not specified by SLS as a member of AnyRef
def readResolve(): AnyRef
- Attributes
- protected
final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
def toString(): String
The name of this enumeration.
- returns
a String representation of the object.
- Definition Classes
- Enumeration → AnyRef → Any
def values: ValueSet
final def wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
final def wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
final def wait(arg0: Long): Unit
final def withName(s: String): Value
Return a Value from this Enumeration whose name matches the argument s. The names are determined automatically via reflection.
- s
an
Enumerationname- returns
the
Valueof thisEnumerationif its name matchess
- Exceptions thrown
NoSuchElementExceptionif noValuewith a matching name is in thisEnumeration
implicit object ValueOrdering extends Ordering[Value]
object ValueSet extends SpecificIterableFactory[Value, ValueSet] with java.io.Serializable
A factory object for value sets
- Annotations
- @SerialVersionUID()
© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.13.0/scala/Enumeration.html
Defines a finite set of values specific to the enumeration. Typically these values enumerate all possible forms something can take and provide a lightweight alternative to case classes.
Each call to a
Valuemethod adds a new unique value to the enumeration. To be accessible, these values are usually defined asvalmembers of the enumeration.All values in an enumeration share a common, unique type defined as the
Valuetype member of the enumeration (Valueselected on the stable identifier path of the enumeration instance).Values SHOULD NOT be added to an enumeration after its construction; doing so makes the enumeration thread-unsafe. If values are added to an enumeration from multiple threads (in a non-synchronized fashion) after construction, the behavior of the enumeration is undefined.
// Define a new enumeration with a type alias and work with the full set of enumerated values object WeekDay extends Enumeration { type WeekDay = Value val Mon, Tue, Wed, Thu, Fri, Sat, Sun = Value } import WeekDay._ def isWorkingDay(d: WeekDay) = ! (d == Sat || d == Sun) WeekDay.values filter isWorkingDay foreach println // output: // Mon // Tue // Wed // Thu // Fri// Example of adding attributes to an enumeration by extending the Enumeration.Val class object Planet extends Enumeration { protected case class Val(mass: Double, radius: Double) extends super.Val { def surfaceGravity: Double = Planet.G * mass / (radius * radius) def surfaceWeight(otherMass: Double): Double = otherMass * surfaceGravity } import scala.language.implicitConversions implicit def valueToPlanetVal(x: Value): Val = x.asInstanceOf[Val] val G: Double = 6.67300E-11 val Mercury = Val(3.303e+23, 2.4397e6) val Venus = Val(4.869e+24, 6.0518e6) val Earth = Val(5.976e+24, 6.37814e6) val Mars = Val(6.421e+23, 3.3972e6) val Jupiter = Val(1.9e+27, 7.1492e7) val Saturn = Val(5.688e+26, 6.0268e7) val Uranus = Val(8.686e+25, 2.5559e7) val Neptune = Val(1.024e+26, 2.4746e7) } println(Planet.values.filter(_.radius > 7.0e6)) // output: // Planet.ValueSet(Jupiter, Saturn, Uranus, Neptune)