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Message:

runFinalizersOnExit

Posted by Michel Feinstein on July 26, 1999 at 2:22 PM

This article http://java.sun.com/products/jdk/1.2/docs/guide/misc/threadPrimitiveDeprecation.html says that runFinalizersOnExit is deprecated because of Thread use. It seems to me that the result of this implies that programmers should explicitly close non-memory resource and not expect some c-like destructor is going to do this for them. Does this sound right?

> > Are there any required actions of the jvm when the java process
> > is interrupted (like using ctrl-c). There doesn't seem to be.

> I don't know for certain. I would expect that if you have
> called runFinalizersOnExit(true) that the finalizers should
> be run even when going down because of an interrupt. Does
> anyone know for sure?

> > Also, upon normal exit, finalizers may not run even if the
> > object is no longer referenced and even if a System.gc() is
> > issued.
> >
> Yup. System.gc() is always just a hint to the VM that
> this would be a good time to do garbage collection. The VM
> can decide what to do. (Some VMs may decide to always GC when
> System.gc() is called. Others may completely ignore
> System.gc(). Others may land somewhere in between.)

> > You might want to mention the System.runFinalizersOnExit( )
> > method, which forces finalizers to be run upon normal system exit.
> > These seem to run even if the object is still referenced.

> I thought I mentioned that...Yes, I just checked and this
> is already mentioned in the article, where I said:

> One more rule of thumb about finalizers concerns objects left on the heap at the end of the application's lifetime. By default, the
> garbage collector will not execute the finalizers of any objects left on the heap when the application exits. To change this
> default, you must invoke the runFinalizersOnExit() method of class Runtime or System, passing true as the single
> parameter. If your program contains objects whose finalizers must absolutely be invoked before the program exits, be sure to
> invoke runFinalizersOnExit() somewhere in your program.

> bv