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Metodo Java Enum ordinal()

Il metodo ordinal() della classe Enum restituisce l'ordinale di questa costante di enumerazione.

Questo metodo è progettato per essere utilizzato da sofisticate strutture dati basate su enumerazione, come EnumSet ed EnumMap.

Sintassi

 public final int ordinal() 

Valore di ritorno

Il metodo ordinal() restituisce l'ordinale di questa costante di enumerazione.

Esempio 1

 public class Enum_ordinalMethodExample1 { enum Colours{ Red,Green,Brown,Yellow; } public static void main(String[] args) { Colours Red = Colours.Red; Colours Green = Colours.Green; Colours Brown = Colours.Brown; Colours Yellow = Colours.Yellow; System.out.println(' Red ordinal = '+Red.ordinal()); System.out.println(' Green Ordinal = '+Green.ordinal()); System.out.println(' Brown Ordinal = '+Brown.ordinal()); System.out.println(' Yellow Ordinal = '+Yellow.ordinal()); } } 
Provalo adesso

Produzione:

 Red ordinal = 0 Green Ordinal = 1 Brown Ordinal = 2 Yellow Ordinal = 3 

Esempio 2

 public class Enum_ordinalMethodExample2 { enum Position{ Reema('Panda'),Himanshu('Bhardwaj'),Geetanjali('Sharma'); String lName; Position(String s){ lName=s; } String showPosition(){ return lName; } } public static void main(String[] args) { for(Position pos : Position.values()){ int val = pos.ordinal()+1; System.out.println('First name = '+pos+'
Last name = '+pos.showPosition() +'
Position in class = '+val ); System.out.println(); } } } 
Provalo adesso

Produzione:

 First name = Reema Last name = Panda Position in class = 1 First name = Himanshu Last name = Bhardwaj Position in class = 2 First name = Geetanjali Last name = Sharma Position in class = 3 

Esempio 3

 public class Enum_ordinalMethodExample3 { enum movie{ Don,DDlJ,Fan,Zero,VeerZara; } public static void main(String[] args) { movie Don,DDLJ,Fan,Zero; Zero= movie.Zero; System.out.println('Movies of Shahrukh Khan:'); for(movie m:movie.values()){ // method will return the ordinals of the enum constants System.out.println(m.ordinal()+' '+m); } System.out.println('Q In which movie Shah rukh khan has played a dual role ?'); String obj1='Don'; String obj2 ='Zero'; Boolean b1 =obj1.equals(obj2); System.out.println('Ans. '+Zero.ordinal()+' '+ obj2 ); if(b1==true){ System.out.println('Your answer is correct.'); } else{ System.out.println('Sorry!You Failed.
 The Correct answer is Don.'); } } } 
Provalo adesso

Produzione:

 Movies of Shahrukh Khan: 0 Don 1 DDlJ 2 Fan 3 Zero 4 VeerZara Q In which movie Shah rukh khan has played a dual role ? Ans. 3 Zero Sorry!You Failed. The Correct answer is Don.