Mantis's GTK+ Look&Feel looks mostly fine, but the JFileChooser seems to have a bug in the filename completion. I run SwingSet2.jar from the demos dir, go to the file chooser pane, invoke a plain JFileChooser, and with the cursor in the filename field and the current directory my home directory (the default), I type a couple letters matching a prefix of a folder in my home dir, and press TAB. Java freezes immediately (and reproducibly):

"AWT-EventQueue-0" prio=1 tid=0x0815cdf0 nid=0xc29 runnable [4d934000..4d9358b8]
at com.sun.java.swing.plaf.gtk.SynthFileChooserUI.getCommonStartString(SynthFileChooserUI.java:646)
at com.sun.java.swing.plaf.gtk.SynthFileChooserUI.updateFileNameCompletion(SynthFileChooserUI.java:619)
at com.sun.java.swing.plaf.gtk.SynthFileChooserUI.access$000(SynthFileChooserUI.java:32)
at com.sun.java.swing.plaf.gtk.SynthFileChooserUI$DelayedSelectionUpdater.run(SynthFileChooserUI.java:199)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:178)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:454)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:141)
at java.awt.Dialog$1.run(Dialog.java:540)
at java.awt.Dialog.show(Dialog.java:561)
at javax.swing.JFileChooser.showDialog(JFileChooser.java:696)
[etc.]

The method getCommonStartString has a while-loop which appears to only be terminated under certain conditions; I am guessing that those conditions are not hit and the loop runs endlessly. The thread dump always shows the PC in the line "i++".

I am using Mantis b19:

java version "1.4.2-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2-beta-b19)
Java HotSpot(TM) Client VM (build 1.4.2-beta-b19, mixed mode)

###@###.### 2003-04-03
###@###.### 2003-04-03