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From: Eric Sosman <esosman@ieee-dot-org.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: verbose sort
Date: Thu, 02 Aug 2012 12:28:58 -0400
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On 8/2/2012 11:37 AM, bob smith wrote:
> I have some code that sorts a list like so:
>
> Vector<String> my_list = new Vector<String>();
>
>
> 		Comparator<String> c = new Comparator<String>() {
> 			@Override
> 			public int compare(String object1, String object2) {
> 				if (object1 == null)
> 					return -1;
> 				if (object2 == null)
> 					return 1;
> 				object1 = object1.toLowerCase();
> 				object2 = object2.toLowerCase();
> 				return object1.compareTo(object2);
> 			};
> 		};
>
> Collections.sort(my_list, c);
>
>
> This seems like a lot of code for such a common operation.  Is there a more succinct way of doing this?

     Consider using compareToIgnoreCase().  Also, think about what
happens when two null's are compared: You should return zero rather
than declaring one of them "less than" the other, because otherwise
your comparator is inconsistent (you can have A<B, B<C, but C<A).

	public int compare(String s1, String s2) {
	    if (s1 == null)
	        return s2 == null ? 0 : -1;
	    return s2 == null ? +1 : s1.compareToIgnoreCase(s2);
	}

-- 
Eric Sosman
esosman@ieee-dot-org.invalid