Re: IO pattern

From:

markspace <nospam@nowhere.com>

Newsgroups:

comp.lang.java.help

Date:

Sat, 11 Dec 2010 11:28:14 -0800

Message-ID:

<ie0jcl$i8b$1@news.eternal-september.org>

On 12/11/2010 6:59 AM, Lew wrote:

In the special case of resource release, e.g., 'iStream.close()', I
often use a simple wrapper method:

private void close( InputStream str )
{
try
{
str.close();
}
catch( IOException exc )
{
final String msg = "Failure to close";
logger.error( msg, exc );
}
}

Or such ...

I've done something similar as a simple utility method. Typed from
memory, not checked:

   public void closeAll( Closeable... closeables ) {
   {
      for( Closeable c : closeables ) {
        try {
           if( c != null ) {
             c.close();
           }
        } catch( IOException ex ) {
          logger.log( Level.SEVERE, null, ex );
        }
     }
   }

The check for null is there to catch the case where the reference has
not been initialized yet. Maybe we throw an exception trying to open
the file, for example, and no object was returned.

This isn't perfect. There are a few things that don't implement
Closeable, so you'll need separate methods for them. But you can also
have this method guarantee its arguments are closed in the order given,
so there's if the caller needs a particular order it's available.