forcing a finalize method to run

[new2java]

In the proceeding code I want to force the finalize method to run for 'a'
(a reference of Type 'A' that is pointing to and object of type 'B') when
it is assigned a null. I want to verify that the finalize method for class
B will run and that the output will be "class B". As it stands, there is
no output when the code is run.

What am I doing wrong?

class A {
int x;
protected void finalize () throws Throwable {System.out.println(" class
A");}
}


class B extends A{
int x;
protected void finalize () throws Throwable {System.out.println(" class
B");}
public static void main (String [] args) {
A a = new B();
a = null;

System.runFinalization();
System.gc();
}
}

[Christian Yungk]

Hello,

My guess is that you are running into problems with it not running the finalization
because you are only "suggesting" to the JVM to run the finalizer and garbage
collection. System.gc() and I believe System.runFinalization() are both
really just suggestions to the JVM. The JVM still determines when it wants
to actually peform these actions. Try running the same code and then generating
a lot of bogus object references to eat up your allocated memory. That way
the garbage collection should run.


"new2java" <mswirt@aol.com> wrote:
>
>In the proceeding code I want to force the finalize method to run for 'a'
>(a reference of Type 'A' that is pointing to and object of type 'B') when
>it is assigned a null. I want to verify that the finalize method for class
>B will run and that the output will be "class B". As it stands, there is
>no output when the code is run.
>
>What am I doing wrong?
>
>class A {
> int x;
> protected void finalize () throws Throwable {System.out.println(" class
>A");}
>}
>
>
>class B extends A{
> int x;
> protected void finalize () throws Throwable {System.out.println(" class
>B");}
> public static void main (String [] args) {
> A a = new B();
> a = null;
>
> System.runFinalization();
> System.gc();
> }
>}
>