Scala Library
scala

class Enumeration
[source: scala/Enumeration.scala]
@serializable

@SerialVersionUID(8476000850333817230L)

abstract class Enumeration(initial : Int, names : java.lang.String*)
extends AnyRef

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 Value method adds a new unique value to the enumeration. To be accessible, these values are usually defined as val members of the evaluation.

All values in an enumeration share a common, unique type defined as the Value type member of the enumeration (Value selected on the stable identifier path of the enumeration instance).

Example use 

  object Main extends Application {

    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.iterator filter isWorkingDay foreach println
  }
Parameters
initial - The initial value from which to count the integers that identifies values at run-time.
names - The sequence of names to give to this enumeration's values.
Author
Matthias Zenger
Version
1.0, 10/02/2004
Direct Known Subclasses:
BigDecimal.RoundingMode, Alignment, BorderPanel.Position, FileChooser.Result, FileChooser.SelectionMode, FlowPanel.Alignment, FormattedTextField.FocusLostBehavior, GridBagPanel.Fill, GridBagPanel.Anchor, ListView.IntervalMode, Orientation, Dialog.Message, Dialog.Options, Dialog.Result, ScrollPane.BarPolicy, TabbedPane.Layout, Table.AutoResizeMode, Table.IntervalMode, Table.ElementMode, Key, Key.Location
Additional Constructor Summary
def this : Enumeration
def this (names : java.lang.String*) : Enumeration
Value Summary
protected var nextId : Int
The integer to use to identify the next created value.
protected var nextName : Iterator[java.lang.String]
The string to use to name the next created value.
Method Summary
protected final def Value : Value
Creates a fresh value, part of this enumeration.
protected final def Value (name : java.lang.String) : Value
Creates a fresh value, part of this enumeration, called name.
protected final def Value (i : Int, name : java.lang.String) : Value
Creates a fresh value, part of this enumeration, called name and identified by the integer i.
protected final def Value (i : Int) : Value
Creates a fresh value, part of this enumeration, identified by the integer i.
final def apply (x : Int) : Value
The value of this enumeration with given id `x`
def exists (p : (Value) => Boolean) : Boolean
Apply a predicate p to all values of this enumeration and return true, iff there is at least one value for which p yields true.
def filter (p : (Value) => Boolean) : Iterator[Value]
Returns all values of this enumeration that satisfy the predicate p. The order of values is preserved.
def flatMap [B](f : (Value) => Iterator[B]) : Iterator[B]
Applies the given function f to each value of this enumeration, then concatenates the results.
def forall (p : (Value) => Boolean) : Boolean
Apply a predicate p to all values of this enumeration and return true, iff the predicate yields true for all values.
def foreach (f : (Value) => Unit) : Unit
Apply a function f to all values of this enumeration.
final def iterator : Iterator[Value]
A new iterator over all values of this enumeration.
def map [B](f : (Value) => B) : Iterator[B]
Returns an iterator resulting from applying the given function f to each value of this enumeration.
final def maxId : Int
The highest integer amongst those used to identify values in this enumeration.
def name : java.lang.String
The name of this enumeration.
override def toString : java.lang.String
The name of this enumeration.
def valueOf (s : java.lang.String) : Option[Value]
def values : ValueSet
The values of this enumeration as a set.
def withName (s : java.lang.String) : Value
Returns a Value from this Enumeration whose name matches the argument s. You must pass a String* set of names to the constructor, or initialize each Enumeration with Value(String), for valueOf to work.
Methods inherited from AnyRef
getClass, hashCode, equals, clone, notify, notifyAll, wait, wait, wait, finalize, ==, !=, eq, ne, synchronized
Methods inherited from Any
==, !=, isInstanceOf, asInstanceOf
Class Summary
protected class Val (i : Int, name : java.lang.String) extends Value
A class implementing the Value type. This class can be overriden to change the enumeration's naming and integer identification behaviour.
abstract class Value extends Ordered[Value]
The type of the enumerated values.
class ValueSet (val ids : BitSet) extends Set[Value] with SetTemplate[Value, ValueSet]
A class for sets of values Iterating through this set will yield values in increasing order of their ids.
Object Summary
object ValueSet extends AnyRef
A factory object for value sets
Additional Constructor Details
def this : Enumeration
def this(names : java.lang.String*) : Enumeration
Value Details
protected var nextId : Int
The integer to use to identify the next created value.
protected var nextName : Iterator[java.lang.String]
The string to use to name the next created value.
Method Details
override def toString : java.lang.String
The name of this enumeration.
def values : ValueSet
The values of this enumeration as a set.
final def maxId : Int
The highest integer amongst those used to identify values in this enumeration.
final def apply(x : Int) : Value
The value of this enumeration with given id `x`
def withName(s : java.lang.String) : Value
Returns a Value from this Enumeration whose name matches the argument s. You must pass a String* set of names to the constructor, or initialize each Enumeration with Value(String), for valueOf to work.
Parameters
s - an enumeration name
Returns
Some(Value) if an enumeration's name matches s, else None Note the change here is intentional. You should know whether a name is in an Enumeration beforehand. If not, just use find on values.
protected final def Value : Value
Creates a fresh value, part of this enumeration.
protected final def Value(i : Int) : Value
Creates a fresh value, part of this enumeration, identified by the integer i.
Parameters
i - An integer that identifies this value at run-time. It must be unique amongst all values of the enumeration.
Returns
..
protected final def Value(name : java.lang.String) : Value
Creates a fresh value, part of this enumeration, called name.
Parameters
name - A human-readable name for that value.
protected final def Value(i : Int, name : java.lang.String) : Value
Creates a fresh value, part of this enumeration, called name and identified by the integer i.
Parameters
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
..
@deprecated("use toString instead")

def name : java.lang.String
The name of this enumeration.
@deprecated("use withName instead")

def valueOf(s : java.lang.String) : Option[Value]
@deprecated("use values.iterator instead")

final def iterator : Iterator[Value]
A new iterator over all values of this enumeration.
@deprecated("use values.foreach instead")

def foreach(f : (Value) => Unit) : Unit
Apply a function f to all values of this enumeration.
@deprecated("use values.forall instead")

def forall(p : (Value) => Boolean) : Boolean
Apply a predicate p to all values of this enumeration and return true, iff the predicate yields true for all values.
@deprecated("use values.exists instead")

def exists(p : (Value) => Boolean) : Boolean
Apply a predicate p to all values of this enumeration and return true, iff there is at least one value for which p yields true.
@deprecated("use values.map instead")

def map[B](f : (Value) => B) : Iterator[B]
Returns an iterator resulting from applying the given function f to each value of this enumeration.
@deprecated("use values.flatMap instead")

def flatMap[B](f : (Value) => Iterator[B]) : Iterator[B]
Applies the given function f to each value of this enumeration, then concatenates the results.
@deprecated("use values.filter instead")

def filter(p : (Value) => Boolean) : Iterator[Value]
Returns all values of this enumeration that satisfy the predicate p. The order of values is preserved.
Scala Library