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Java language bindings for Gobject, generated with Java-GI
There is a newer version: 0.11.2
/* Java-GI - Java language bindings for GObject-Introspection-based libraries
 * Copyright (C) 2022-2023 Jan-Willem Harmannij
 *
 * SPDX-License-Identifier: LGPL-2.1-or-later
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see .
 */

 /* This file has been generated with Java-GI.
  * Do not edit this file directly!
  * Visit https://jwharm.github.io/java-gi for more information.
  */

package org.gnome.gobject;

import io.github.jwharm.javagi.gobject.*;
import io.github.jwharm.javagi.gobject.types.*;
import io.github.jwharm.javagi.base.*;
import io.github.jwharm.javagi.interop.*;
import java.lang.foreign.*;
import java.lang.invoke.*;
import org.jetbrains.annotations.*;

/**
 * A {@link WeakNotify} function can be added to an object as a callback that gets
 * triggered when the object is finalized.
 * 
 * Since the object is already being disposed when the {@link WeakNotify} is called,
 * there's not much you could do with the object, apart from e.g. using its
 * address as hash-index or the like.
 * 

 * In particular, this means it’s invalid to call g_object_ref(),
 * g_weak_ref_init(), g_weak_ref_set(), g_object_add_toggle_ref(),
 * g_object_weak_ref(), g_object_add_weak_pointer() or any function which calls
 * them on the object from this callback.
 */
@FunctionalInterface
public interface WeakNotify {

    /**
     * A {@link WeakNotify} function can be added to an object as a callback that gets
     * triggered when the object is finalized.
     * 

     * Since the object is already being disposed when the {@link WeakNotify} is called,
     * there's not much you could do with the object, apart from e.g. using its
     * address as hash-index or the like.
     * 
     * In particular, this means it’s invalid to call g_object_ref(),
     * g_weak_ref_init(), g_weak_ref_set(), g_object_add_toggle_ref(),
     * g_object_weak_ref(), g_object_add_weak_pointer() or any function which calls
     * them on the object from this callback.
     */
    void run(@Nullable java.lang.foreign.MemorySegment data, org.gnome.gobject.GObject whereTheObjectWas);
    
    /**
     * The {@code upcall} method is called from native code. The parameters 
     * are marshalled and {@link #run} is executed.
     */
    @ApiStatus.Internal default void upcall(MemorySegment data, MemorySegment whereTheObjectWas) {
        run(data,
                (org.gnome.gobject.GObject) InstanceCache.getForType(whereTheObjectWas, org.gnome.gobject.GObject::new, false));
    }
    
    /**
     * Creates a callback that can be called from native code and executes the {@code run} method.
     * @return the memory address of the callback function
     */
    default MemorySegment toCallback() {
        FunctionDescriptor _fdesc = FunctionDescriptor.ofVoid(ValueLayout.ADDRESS, ValueLayout.ADDRESS);
        MethodHandle _handle = Interop.upcallHandle(MethodHandles.lookup(), WeakNotify.class, _fdesc);
        return Linker.nativeLinker().upcallStub(_handle.bindTo(this), _fdesc, SegmentScope.global());
    }
}