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Re: unnecessary code in Oracle example?

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markspace <markspace@nospam.nospam> writes:

> On 10/9/2013 12:08 PM, Jim Janney wrote:
>>
>> 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.
>>
>
> I don't like either one.  Why not take advantage of the fact that
> resources are specified to be closed in the opposite order that they
> are declared in a try-with-resources?
>
> The following demonstrates this by closing the named streams in the
> order C-B-A:
>
>
> package quicktest;
>
> import java.io.IOException;
> import java.io.InputStream;
>
> public class TryResourcesTest
> {
>    public static void main( String[] args ) throws Exception
>    {
>       try(
>           MyTestStream a = new MyTestStream( "A" );
>           MyTestStream b = new MyTestStream( "B" );
>           MyTestStream c = new MyTestStream( "C" )
>       ) {
>          System.out.println( a.read()+b.read()+c.read() );
>       }
>    }
> }
>
> class MyTestStream extends InputStream {
>
>    private final String name;
>
>    public MyTestStream( String name )  {
>       this.name = name;
>    }
>
>    @Override
>    public int read() throws IOException  {
>       return 42;
>    }
>
>    @Override
>    public void close() {
>       System.out.println( getClass().getSimpleName()+
>        ":"+name+" closed." );
>    }
> }

Yes, in Java 7 you can have clean syntax and clean semantics.  Looks
like a win all around.

-- 
Jim Janney

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unnecessary code in Oracle example? Jim Janney <jjanney@shell.xmission.com> - 2013-10-09 10:38 -0600
  Re: unnecessary code in Oracle example? Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2013-10-09 11:19 -0700
    Re: unnecessary code in Oracle example? ram@zedat.fu-berlin.de (Stefan Ram) - 2013-10-09 19:04 +0000
    Re: unnecessary code in Oracle example? Jim Janney <jjanney@shell.xmission.com> - 2013-10-09 13:08 -0600
      Re: unnecessary code in Oracle example? markspace <markspace@nospam.nospam> - 2013-10-09 12:27 -0700
        Re: unnecessary code in Oracle example? Jim Janney <jjanney@shell.xmission.com> - 2013-10-09 14:21 -0600
          Re: unnecessary code in Oracle example? markspace <markspace@nospam.nospam> - 2013-10-09 14:56 -0700
            Re: unnecessary code in Oracle example? Jim Janney <jjanney@shell.xmission.com> - 2013-10-09 20:56 -0600
              Re: unnecessary code in Oracle example? Arivald <NOSPAMarivald@interia.pl> - 2013-10-10 06:42 +0200
                Re: unnecessary code in Oracle example? Sebastian <news@seyweiler.dyndns.org> - 2013-10-10 07:47 +0200
                Re: unnecessary code in Oracle example? Arivald <arivald_@AT_interia_DOT_.pl> - 2013-10-10 10:26 +0200
                Re: unnecessary code in Oracle example? Jim Janney <jjanney@shell.xmission.com> - 2013-10-10 08:47 -0600
    Re: unnecessary code in Oracle example? Robert Klemme <shortcutter@googlemail.com> - 2013-10-09 21:11 +0200
      Re: unnecessary code in Oracle example? cuzdav@gmail.com - 2013-10-10 08:49 -0700

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