Re: Closing Files that Weren't Successfully Opened

From:
Lew <noone@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Wed, 16 Mar 2011 09:52:16 -0400
Message-ID:
<ilqfaf$bes$1@news.albasani.net>
On 03/16/2011 08:11 AM, Michal Kleczek wrote:

Lew wrote:

Michal Kleczek wrote:

Lew wrote:

  Michal Kleczek wrote:

Lew wrote:

Michal Kleczek wrote:


A file handle. You do not call close() on FileReader in case
BufferedReader constructor throws.


Non-issue. If FileReader doesn't then BufferedReader won't.


1. It can always throw a RuntimeException or an Error. Depending on
situation it should or should not be handled gracefully hence it _can_ be
an issue. If it is a library (reusable) code it certainly is.


If it throws an Error your resources are released because the program
crashes.
   Same for RuntimeException.


I know of a lot of cases when the program will not (and should not) crash
after RuntimeException (or even an Error).
Are you suggesting to write non-robust code leading to potential resource
leaks?


No.

2. My original reply to Robert's post was:

<quote>
That only works because both InputStreamReader and BufferedReader
constructors don't throw.
But it is not safe to do the same for:
final ObjectInputStream ois =
    new ObjectInputStream(new FileInputStream("foo.txt"));
</quote>

You've read it before replying, haven't you?


and you were mistaken then, too.


If FileInputStream doesn't have an I/O error, then ObjectInputStream won't,
either. The I/O condition will have been handled by the time the OIS is
constructed.

BOOYAH!

--
Lew
Honi soit qui mal y pense.

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