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/*
* java-gnome, a UI library for writing GTK and GNOME programs from Java!
*
* Copyright © 2006-2010 Operational Dynamics Consulting, Pty Ltd
*
* The code in this file, and the program it is a part of, is made available
* to you by its authors as open source software: you can redistribute it
* and/or modify it under the terms of the GNU General Public License version
* 2 ("GPL") as published by the Free Software Foundation.
*
* This program 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 GPL for more details.
*
* You should have received a copy of the GPL along with this program. If not,
* see http://www.gnu.org/licenses/. The authors of this program may be
* contacted through http://java-gnome.sourceforge.net/.
*/
import java.util.HashSet;
import org.freedesktop.bindings.Debug;
import org.gnome.gdk.Event;
import org.gnome.gtk.Button;
import org.gnome.gtk.Gtk;
import org.gnome.gtk.Label;
import org.gnome.gtk.VBox;
import org.gnome.gtk.Widget;
import org.gnome.gtk.Window;
/**
* Fork of Experiment to specifically test memory management under limited and
* almost controllable conditions. This is not example code!
*
* @author Andrew Cowie
*/
public final class Toggling
{
private HashSet<Window> set;
/*
* It is not, strictly speaking, necessary to put the UI building code
* into a constructor; there's nothing wrong in a tiny program with doing
* it all in static code in main().
*
* What we gain, however, is that the references to all the objects
* created become unreachable as soon as it runs, and that allowed us to
* evaluate that the memory management is working correctly.
*/
private Toggling() {
final Window w;
final VBox x;
final Button b;
final Button gc;
final Button res;
if (!Debug.MEMORY_MANAGEMENT) {
System.err.println("Debug.MEMORY_MANAGEMENT must be enabled to run this class");
System.exit(1);
}
w = new Window();
set = new HashSet<Window>();
x = new VBox(false, 3);
b = new Button("New window");
x.packStart(b, false, false, 0);
res = new Button("Ressurect");
x.packStart(res, false, false, 0);
res.connect(new Button.Clicked() {
public void onClicked(Button source) {
for (Window w : set) {
w.present();
}
}
});
gc = new Button("Run gc()");
x.packStart(gc, false, false, 0);
gc.connect(new Button.Clicked() {
public void onClicked(Button source) {
System.err.println("Run Java garbage collector");
System.gc();
}
});
w.add(x);
w.setTitle("Toggling");
b.connect(new Button.Clicked() {
public void onClicked(Button source) {
final Window z;
final Label d;
z = new Window();
d = new Label("This is some very very\nimportant data that concerns your future!");
z.add(d);
z.showAll();
set.add(z);
}
});
Button zero = new Button("Drop extra refs");
x.packStart(zero, false, false, 0);
zero.connect(new Button.Clicked() {
public void onClicked(Button source) {
System.err.println("Drop refs");
set = null;
}
});
w.showAll();
w.connect(new Window.DeleteEvent() {
public boolean onDeleteEvent(Widget source, Event event) {
System.out.println("I was deleted!");
Gtk.mainQuit();
return false;
}
});
}
public static void main(String[] args) {
Gtk.init(args);
new Toggling();
System.out.println("Main loop starting...");
Gtk.main();
System.out.println("Main loop exited");
// Observe release() being done on the various Proxies created. As
// ever, though, calling gc() is not imperative.
System.err.println("Run Java garbage collector (last-1 time)");
System.gc();
try {
Thread.sleep(500);
} catch (Exception e) {
// ignore
}
System.err.println("Run Java garbage collector (last time)");
System.gc();
try {
Thread.sleep(500);
} catch (Exception e) {
// ignore
}
// And, hopefully, we make it out of the main loop without crashing
System.out.println("Bye now.");
}
}
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