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From: Robert Klemme <shortcutter@googlemail.com>
Newsgroups: comp.lang.java.programmer
Subject: Usefulness of "final" (Was: Re: Inserting In a List)
Date: Tue, 02 Apr 2013 21:06:25 +0200
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On 04/02/2013 04:08 PM, lipska the kat wrote:

> Just as a matter of interest what's with all the finals
>
> particularly
>
> for (final File name : folder.listFiles())
>
> Despite initial appearances this is indeed legal as the
> assignment is made multiple times but from the same statement.
>
> Given that the final keyword is, aside from a flag to the compiler for
> possible optimization, largely documentary, what is the point of making
> name final.

It helps avoid accidental reassignment.  And it helps distinguish 
unchanged from changed variables.

> In fact what does peppering the code with finals do to make it easily
> understandable to an inexperienced developer ?

I believe in using "final" pretty often as it will immediately indicate 
which local variables are constant for a method call and which are 
modified all the time.  Plus, with "final" you can easier catch errors 
in control flow:

final String x;

if ( someCondition() ) {
   x = y.toString();
}
else {
   if ( someOtherCondition() ) {
     x = "foo";
   }
   // forgot the else branch here
   x = "bar";
}

System.out.println("We got " + x);

Generally I find "finally" quite useful - apparently significantly more 
useful than you do. :-)

Kind regards

	robert