Re: Forwards compatible program possible?

From:
jonasforssell@yahoo.se
Newsgroups:
comp.lang.java.programmer
Date:
25 Jul 2006 13:28:40 -0700
Message-ID:
<1153859319.953874.51260@75g2000cwc.googlegroups.com>
Patricia Shanahan skrev:

jonasforssell@yahoo.se wrote:

Hello Experts,

The 1.4 API has a few very useful functions like
Runnable.getNumberOfProcessors()

Is it possible to write a program which uses these if possible but does
not demand a 1.4 JRE and disables the feature if run on an 1.2 JRE?

If so, how would an example look like?

Thanks
/Jonas Forssell, Gothenburg, Sweden


How about reflection?

       try {
         Method m = Runtime.class.getDeclaredMethod(
             "availableProcessors",new Class[0]);
         Object o = m.invoke(Runtime.getRuntime(),new Object[0]);
         return ((Integer)o).intValue();
       } catch (NoSuchMethodException e) {
         return 1;
       }

You will need more exception handling. The NoSuchMethodException block
should return whatever number of processors you want to assume in the
1.2 JRE.

Patricia


Excellent proposal.
Thanks for your help!
/jonas

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