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From: Robert Klemme <shortcutter@googlemail.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: Using Java Classes to Sort a Small Array Quickly
Date: Thu, 01 Sep 2011 08:32:26 +0200
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On 01.09.2011 04:48, KevinSimonson wrote:
> I have an<enum>  named<ProjectEnum>  that has twelve values.  Today I
> added an instance variable to it, a<String>  named<collectionTitle>.
> The engineer I'm working with asked me to write a static method in
> class<ProjectEnum>  that returns an array of<ProjectEnum>s sorted
> alphabetically by this value<collectionTitle>.

Since we're talking about an enum and I am sure you made field "name" 
final (i.e. to make instances immutable) you can completely ignore sort 
performance.  You just need to sort once.  For example:

package en;

import java.util.Arrays;
import java.util.Comparator;

public enum ProjectEnum {

   P1("xyz"), P2("abc"), P3("def");

   private final String collectionTitle;

   private ProjectEnum(String name) {
     if (name == null) {
       throw new NullPointerException();
     }

     this.collectionTitle = name;
   }

   public String getCollectionTitle() {
     return collectionTitle;
   }

   private static final ProjectEnum[] sortedValues;

   static {
     sortedValues = ProjectEnum.values();

     Arrays.sort(sortedValues, new Comparator<ProjectEnum>() {
       @Override
       public int compare(ProjectEnum o1, ProjectEnum o2) {
         return o1.getCollectionTitle().compareTo(o2.getCollectionTitle());
       }
     });
   }

   public static ProjectEnum[] sorted() {
     return Arrays.copyOf(sortedValues, sortedValues.length);
   }
}

Kind regards

	robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/