1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/xpcom/base/nsIWeakReference.idl Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,67 @@
1.4 +/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
1.5 + *
1.6 + * This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#include "nsISupports.idl"
1.11 +
1.12 +
1.13 +/**
1.14 + * An instance of |nsIWeakReference| is a proxy object that cooperates with
1.15 + * its referent to give clients a non-owning, non-dangling reference. Clients
1.16 + * own the proxy, and should generally manage it with an |nsCOMPtr| (see the
1.17 + * type |nsWeakPtr| for a |typedef| name that stands out) as they would any
1.18 + * other XPCOM object. The |QueryReferent| member function provides a
1.19 + * (hopefully short-lived) owning reference on demand, through which clients
1.20 + * can get useful access to the referent, while it still exists.
1.21 + *
1.22 + * @version 1.0
1.23 + * @see nsISupportsWeakReference
1.24 + * @see nsWeakReference
1.25 + * @see nsWeakPtr
1.26 + */
1.27 +[scriptable, uuid(9188bc85-f92e-11d2-81ef-0060083a0bcf)]
1.28 +interface nsIWeakReference : nsISupports
1.29 + {
1.30 + /**
1.31 + * |QueryReferent| queries the referent, if it exists, and like |QueryInterface|, produces
1.32 + * an owning reference to the desired interface. It is designed to look and act exactly
1.33 + * like (a proxied) |QueryInterface|. Don't hold on to the produced interface permanently;
1.34 + * that would defeat the purpose of using a non-owning |nsIWeakReference| in the first place.
1.35 + */
1.36 + void QueryReferent( in nsIIDRef uuid, [iid_is(uuid), retval] out nsQIResult result );
1.37 + };
1.38 +
1.39 +
1.40 +/**
1.41 + * |nsISupportsWeakReference| is a factory interface which produces appropriate
1.42 + * instances of |nsIWeakReference|. Weak references in this scheme can only be
1.43 + * produced for objects that implement this interface.
1.44 + *
1.45 + * @version 1.0
1.46 + * @see nsIWeakReference
1.47 + * @see nsSupportsWeakReference
1.48 + */
1.49 +[scriptable, uuid(9188bc86-f92e-11d2-81ef-0060083a0bcf)]
1.50 +interface nsISupportsWeakReference : nsISupports
1.51 + {
1.52 + /**
1.53 + * |GetWeakReference| produces an appropriate instance of |nsIWeakReference|.
1.54 + * As with all good XPCOM `getters', you own the resulting interface and should
1.55 + * manage it with an |nsCOMPtr|.
1.56 + *
1.57 + * @see nsIWeakReference
1.58 + * @see nsWeakPtr
1.59 + * @see nsCOMPtr
1.60 + */
1.61 + nsIWeakReference GetWeakReference();
1.62 + };
1.63 +
1.64 +
1.65 +%{C++
1.66 +#ifdef MOZILLA_INTERNAL_API
1.67 +#include "nsIWeakReferenceUtils.h"
1.68 +#endif
1.69 +%}
1.70 +
