具有构造函数和显式实例字段以及这些字段的访问器的枚举类型

import java.util.EnumSet;//来自 时 代 J a v a 公 众 号 - N o w J a v  a . c o m

enum Book

{    

   // declare constants of enum type                                

   Java("Java", "2015"),                        

   C("C", "2013"),                           

   Internet("Internet", "2012"),

   Cpp("C++", "2014"),                       

   VB("Visual Basic", "2014"),

   CSharp("Visual C#", "2014");


   // instance fields 

   private final String title; 

   private final String copyrightYear;


   // enum constructor
   /*
   时   代    Java - nowjava.com 提 供
   */

   Book(String title, String copyrightYear) 

   { 

      this.title = title;

      this.copyrightYear = copyrightYear;

   } 


   // accessor for field title

   public String getTitle()

   {

      return title;

   } 


   // accessor for field copyrightYear

   public String getCopyrightYear()

   {

      return copyrightYear;

   } 

} 


public class Main 

{

   public static void main(String[] args) 

   {

      System.out.println("All books:");


      // print all books in enum Book                          

      for (Book book : Book.values())                        

         System.out.printf("%-10s%-45s%s%n", book,

             book.getTitle(), book.getCopyrightYear());


      System.out.printf(