Re: different try-finally approach

From:
Lew <noone@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Tue, 04 Aug 2009 09:26:57 -0400
Message-ID:
<h59cv1$tq6$1@news.albasani.net>
Pitch wrote:

In article <h588io$aq6$1@news.albasani.net>, noone@lewscanon.com
says...>

Pitch wrote:

In both situations constructor is allowed to fail. But in "java [sic] way" [sic] if
constructor fails, the close() statement is never called, so it's pretty
much the same thing, right?

Neither way is a particularly "Java" way.

I guess the bottom line is wheather you'll use internal catch or an
external one. I prefer the external ones, or even dividing the code
between methods.

I prefer:

  public void doSomething()
      // throws [MyResource|App]Exception
  {
   final MyResource res;
   try
   {
     res = new MyResource();
   }
   catch ( MyResourceException exc )
   {
     logger.error( exc );
     return; // or throw exc or new AppException(exc)
   }
   assert res != null;

   try
   {
     // do something with res
   }
   finally
   {
     res.close()
   }
  }


This implies res is not going to get null in the last try-block. I think
this is a real possibility if more programmers work on the code so you'd
still need if != null


No, 'res' is guaranteed not to be null.

--
Lew

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