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#! /usr/bin/env python
import pygtk; pygtk.require("2.0")
import bonobo
import Bonobo
import Bonobo__POA
import CORBA, sys
import gc
gc.set_debug(gc.DEBUG_LEAK)
orb = CORBA.ORB_init(sys.argv)
bonobo.activate()
class PersistStream(Bonobo__POA.PersistStream, bonobo.UnknownBaseImpl):
def __init__(self):
bonobo.UnknownBaseImpl.__init__(self)
# implementations of methods/attributes of "Interface" go here
def load(self, content_type):
print "PersistStream::load(content_type='%s')" % content_type
def save(self, content_type):
print "PersistStream::save(content_type='%s')" % content_type
ps = PersistStream()
def foo(*args):
print args
listener = bonobo.Listener(foo)
listener.add_interface(ps.get_bonobo_object())
del ps
## How is it that the PersistStream servant instance is kept alive, I
## hear you ask?
## Well, there's a signal connection from the 'destroy' signal of
## the ForeignObject to a bound method of the servant instance. A
## bound method object contains an implicit reference to the instance
## to which it is bound. On the other hand, the servant contains a
## reference to the ForeignObject. This way, these two objects keep
## each other alive with mutual references.
## When the 'destroy' signal is fired (when bonobo reference count
## drops to zero), the bound method in the servant is called, and it
## deletes the reference it has to the ForeignObject, thus destroying
## the signal connection (closure), consequently releasing the last
## reference to the servant. At least that's my theory on how things
## work..
print "server-side boundary"
listener = listener.corba_objref() # from now on we work on client-side
gc.collect()
print "client-side"
print "query PersistStream"
ps = listener.queryInterface("IDL:Bonobo/PersistStream:1.0")
print ps
print "unref PersistStream"
if ps is not None:
ps.unref()
gc.collect()
print ">>unref listener start"
# this should trigger final ref count -> destroy
listener.unref()
del listener
print "<<unref listener end"
gc.collect()
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