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From: Jim Janney <jjanney@shell.xmission.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: unnecessary code in Oracle example?
Date: Wed, 09 Oct 2013 13:08:57 -0600
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Daniel Pitts <newsgroup.nospam@virtualinfinity.net> writes:

> You are correct for this case, the other case comes from a block which
> uses multiple resources.
>
> MyResource r1 = null;
> MyResource r2 = null;
>
> try {
>   r1 = openResource1();
>   r2 = openResource2();
> } finally {
>   if (r1 != null) r1.close();
>   if (r2 != null) r2.close();
> }
>
> Of course, some close() methods can throw, which could break this
> idiom too.  This is one reason why C++ forbids destructors from
> throwing.

Thanks.  But that looks like a good idiom to avoid.  I prefer

   MyResource r1 = openResource();
   try {
      MyResource r2 = openResource2();
      try {
        //  do something
      } finally {
        r2.close();
      }
   } finally {
     r1.close();
   }

Not as pretty syntactically, perhaps, but much clearer semantically.

-- 
Jim Janney