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Typesafe Enumerations

• Class with fixed number of instances
  public class Size
  {
     private Size(String name) { this.name = name; }
     private String name;
     public static final Size SMALL = new Size("SMALL");
     public static final Size MEDIUM = new Size("MEDIUM");
     public static final Size LARGE = new Size("LARGE");
  }
• Private constructor!
• String field not necessary (but convenient for toString, serialization)
  
• Typical use:
  Size imageSize = Size.MEDIUM;
  if (imageSize == Size.SMALL) . . .
  
  

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