RFR(s): 8023541 Race condition in rmid initialization

[Alan Bateman]

On 30/01/2014 09:09, Daniel Fuchs wrote:
> Hi Stuart,
>
> I wonder whether you should replace the assert in the
> constructor by an explicit null check:
>
> -  assert systemStub != null
> + if (systemStub == null) throw new NullPointerException();
>
> The reason I see is that before your change, an object constructed
> with a null systemStub would have sooner or later failed in NPE.
> Now with your change, an object constructed with a null system
> stub will block - waiting forever for system stub to become not
> null.
I suspect the system stub can never be null but I agree it should be 
checked before creating the RegistryImpl. One way to do that is by going 
through another constructor, something like this:

     private SystemRegistryImpl(int port,
                                RMIClientSocketFactory csf,
                                RMIServerSocketFactory ssf,
                                ActivationSystem systemStub,
                                Void unused) throws RemoteException {
         super(port, csf, ssf);
         synchronized (this) {
             this.systemStub = systemStub;
             notifyAll();
         }
     }

     SystemRegistryImpl(int port,
                        RMIClientSocketFactory csf,
                        RMIServerSocketFactory ssf,
                        ActivationSystem systemStub) throws 
RemoteException {
         this(port, csf, ssf, Objects.requireNonNull(systemStub), null);
     }

but maybe that it too subtle.

-Alan