[ninf-users:00136] Re: object handle

[Yoshio Tanaka <yoshio.tanaka@aist.go.jp>]

Hi,

From: Fabrizio Messina <messina@dmi.unict.it>
Subject: [ninf-users:00135] Re: object handle
Date: Tue, 14 Mar 2006 08:41:58 +0100
Message-ID: <441673C6.7000101@dmi.unict.it>

messina> Yoshio Tanaka wrote:
messina> > Hi,
messina> > 
messina> > In your example, Ninf-G remote object (O_B) is created on host B by
messina> > calling grpc_object_handle_init_np() on host A.  O_B does exist on
messina> > host B and can be referred by an object handle created on host A.
messina> > 
messina> > I'm not sure what "serialized" mean, but the object handle is a C
messina> > structure and kept in a variable on host A.  Thus, the object handle
messina> > is not valid on host C and no handles on host C could invoke
messina> > methods of O_B which was created on host A.
messina> 
messina> I wanted to say "Object Serialization" in Java. I referred to Ninf-G 
messina> Java API, in particular instances of GrpcObjectHandle class.
messina> 
messina> But, let's suppose that a Ninf-G remote object was created on host B by 
messina> a call to grpc_oject_handle_init_np(), or by Java method 
messina> GrpcClient.getObjectHandle() from host A, as in primer example. Would it 
messina> be possible to localize the existing Ninf-G object from host C, and 
messina> create an handle to the its? If not, perhaps, may be a limitation?

Would you like to create an object handle to an existing Ninf-G
object, i.e. create two object handles to the same object?
It is impossible.  It is not by a limitation but by semantics of
Ninf-G object.

Ninf-G objects keep status, but the scope of an Ninf-G object is
limited to the Ninf-G client which created the Ninf-G object.
Ninf-G object cannot be referred by the other processes.

Regards,

--
Yoshio Tanaka (yoshio.tanaka@aist.go.jp)
http://ninf.apgrid.org/
http://www.apgridpma.org/


messina> 
messina> Thank you very much, Fabrizio.
messina> > 
messina> > Regards,
messina> > 
messina> > --
messina> > Yoshio Tanaka (yoshio.tanaka@aist.go.jp)
messina> > http://ninf.apgrid.org/
messina> > http://www.apgridpma.org/
messina> > 
messina> > From: Fabrizio Messina <messina@dmi.unict.it>
messina> > Subject: [ninf-users:00133] object handle
messina> > Date: Mon, 13 Mar 2006 20:40:19 +0100
messina> > Message-ID: <4415CAA3.2040103@dmi.unict.it>
messina> > 
messina> > messina> Hi all,
messina> > messina> 
messina> > messina> I'm a Ph.D Student and I have a question about Ninf-G "remote object" 
messina> > messina> and its "handle".
messina> > messina> 
messina> > messina> What's the scope of an "object handle" (say, instance of 
messina> > messina> GrpcObjectHandle class)? If an handle to some Ninf-G Object, say O_B 
messina> > messina> (located in host B), is created on host A, and the handle is 
messina> > messina> "serialized" to host C, is the handle valid on host C to invoke methods 
messina> > messina> of O_B?
messina> > messina> 
messina> > messina> Thank you in advance, Fabrizio.
messina> > 
messina>