Package org.codehaus.janino.util.enumerator

Class Enumerator

java.lang.Object
org.codehaus.janino.util.enumerator.Enumerator
Direct Known Subclasses:
Access, Parser.ClassDeclarationContext, Parser.InterfaceDeclarationContext
public abstract class Enumerator extends Object
A class that represents an enumerated value. Its main features are its toString() and fromString(String, Class) method, which map names to values and vice versa.

To use this class, derive from it and define one or more public static final fields, as follows: 

 public final class Suit extends Enumerator {

     // Exactly N instances of "Suit" exist to represent the N possible values.
     public static final Suit CLUBS    = new Suit("clubs");
     public static final Suit DIAMONDS = new Suit("diamonds");
     public static final Suit HEARTS   = new Suit("hearts");
     public static final Suit SPADES   = new Suit("spades");

     // Optional, if you want to use EumeratorSet arithmetics.
     public static final EnumeratorSet NONE = new EnumeratorSet(Suit.class      ).setName("none");
     public static final EnumeratorSet ALL  = new EnumeratorSet(Suit.class, true).setName("all");

     // These MUST be declared exactly like this:
     private Suit(String name) { super(name); }
     public static Suit fromString(String name) throws EnumeratorFormatException {
         return (Suit) Enumerator.fromString(name, Suit.class);
     }
 }
See Also:

  • Constructor Details

    • Enumerator

      protected Enumerator(String name)
      Initialize the enumerator to the given value.

  • Method Details

    • equals

      public final boolean equals(Object that)
      Equality is reference identity.
      Overrides:
      equals in class Object

    • hashCode

      public final int hashCode()
      Enforce Object's notion of Object.hashCode().
      Overrides:
      hashCode in class Object

    • fromString

      protected static final Enumerator fromString(String name, Class enumeratorClass) throws EnumeratorFormatException
      Initialize an Enumerator from a string.

      The given string is converted into a value by looking at all instances of the given type created so far.

      Derived classes should invoke this method as follows:

       public class Suit extends Enumerator {
     ...
     public static Suit fromString(String name) throws EnumeratorFormatException {
         return (Suit) Enumerator.fromString(name, Suit.class);
     }
 }
      Throws:
      EnumeratorFormatException - if the string cannot be identified

    • toString

      public String toString()
      Returns the name passed to Enumerator(String).
      Overrides:
      toString in class Object