Richard Jones wrote:
>
> Can someone tell me why this program, when run under
> Linux, prints d = 0 (ie. the variable d isn't being
> initialized as expected)? According to Bruce Eckel's
> book, which is the only reference I have available to
> me, d should be initialized to 1, so I suspect this
> may be a JVM bug ...
Have you tried it on JVMs other than Linux?
It looks to me like you're invoking method() before DerivedClass has
been fully initialized... not entirely surprising, since the super()
constructor must occur before any constructor activity in the derived
class. (Try, for example, inserting some code before the super() call
and you'll be scolded by the compiler. The initialization of d is
comparable activity.)
Nathan Meyers
[EMAIL PROTECTED]
> ---------------------------------------------------------
> /* SuperClass.java */
>
> public abstract class SuperClass
> {
> protected SuperClass ()
> {
> method ();
> }
>
> protected abstract void method ();
> }
> ---------------------------------------------------------
>
> ---------------------------------------------------------
> /* DerivedClass.java */
>
> public class DerivedClass extends SuperClass
> {
> public int d = 1;
>
> public DerivedClass ()
> {
> super ();
> }
>
> protected void method ()
> {
> System.out.println ("d = " + d);
> }
>
> public static void main (String[] args)
> {
> DerivedClass derivedClass = new DerivedClass ();
> }
> }
> ---------------------------------------------------------
>
> $ java -version
> java version "1.1.6"
> $ java DerivedClass
> d = 0
>
> --
> - Richard Jones. Linux contractor London and SE areas. -
> - Very boring homepage at: http://www.annexia.demon.co.uk/ -
> - You are currently the 1,991,243,100th visitor to this signature. -
> - Original message content Copyright (C) 1998 Richard Jones. -
