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From: Wanja Gayk <brixomatic@yahoo.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: are lambdas a way to bring functional programming to java?
Date: Sat, 28 Jun 2014 14:43:59 +0200
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In article <53ae0af4$0$302$14726298@news.sunsite.dk>, Arne Vajhøj 
(arne@vajhoej.dk) says...

> Here is a simple example.
> 
> Java 7 code:
> 
> Collections.sort(lst, new Comparator<String>() {
>      public int compare(String s1, String s2) {
>          return s1.length() - s2.length();
>      }
> });
> 
> Java 8 code:
> 
> Collections.sort(lst, (s1,s2) -> s1.length() - s2.length());
> 
> I do not see any value in the extra code in the 7 version.

I fear Java8's Lambdas may not encourage reuse so much as the Java 7 
way. This does seem to be a pretty standard comparator, so I would 
probably code it this way:

static final Comparator<String> COMPARE_BY_LENGTH = new Comparator<>{
      public int compare(String s1, String s2) {
          return s1.length() - s2.length();
      }
 });

Collections.sort(lst, COMPARE_BY_LENGTH);

Just because using it looks better.
Of course in Java 8 it could look like this (sorry for the bad line 
breaks:

static final Comparator<String> COMPARE_BY_LENGTH 
              = (s1,s2) -> s1.length() - s2.length()

Collections.sort(lst, COMPARE_BY_LENGTH);

..or even implementing a more general interface.
But would people do that very often, if the original expression is so 
concise? Hmm..

Kind regards,
Wanja

-- 
..Alesi's problem was that the back of the car was jumping up and down 
dangerously - and I can assure you from having been teammate to 
Jean Alesi and knowing what kind of cars that he can pull up with, 
when Jean Alesi says that a car is dangerous - it is. [Jonathan Palmer]

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