Enums and Template Methods

问题

Enum is basically a special class type, and can have methods and fields just like any other class. Any one know about the Enums Template Methods. Please give a real example for Template Methods on Enums. And can you explain about Enum Reverse Lookups.

回答1:

Java 5.0 Enum tricks, specially have a look on the video.

Here is a simple example of a "command" enumeration:

public enum Toy {
     DOLL() {
          @Override public void execute() { 
               System.out.println("I'm a doll."); 
          }
     },
     SOLDIER() {
          @Override public void execute() { 
               System.out.println("I'm a soldier."); 
          }
     };
     //template method
     public abstract void execute();
}

Here objects Doll and Soldier both have a different implementation of the function execute().

回答2:

Applying the "Template Method" design pattern, one can create enumerations that are factories or command objects, but a defined set of objects. Here is a simple example of a "command" enumeration:

you will also get explanation of Enum Reverse Lookups over the above link

来源：https://stackoverflow.com/questions/8799936/enums-and-template-methods