Re: Closing Files that Weren't Successfully Opened

From:

Lew <noone@lewscanon.com>

Newsgroups:

comp.lang.java.programmer

Date:

Tue, 15 Mar 2011 07:54:17 -0400

Message-ID:

<ilnk05$b75$2@news.albasani.net>

On 03/15/2011 06:53 AM, Michal Kleczek wrote:

On Tue, 15 Mar 2011 03:41:15 -0700, Robert Klemme wrote:

If you want BufferedReader you can do

final BufferedReader reader =
   new BufferedReader(new InputStreamReader(new
FileInputStream("foo.txt")));
try {
   for (String line; (line = reader.readLine()) != null;) {
     System.out.println("Found line: " + line);
   }
}
finally {
   reader.close();
}

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"));

That's covered upthread five and a half hours prior to the cited post.

Sometimes it would be good to have destructors...

Nonsense. Destructors are to release memory. This is about external
resources. What Java needs are 'finally' blocks. Hey, good news! It's got
them! Yay! Problem solved!

--
Lew
Honi soit qui mal y pense.