JDK-4676398 : dragEnter freezes the system window manager (jdk1.4 regression)
  • Type: Bug
  • Component: client-libs
  • Sub-Component: java.awt
  • Affected Version: 1.4.0
  • Priority: P2
  • Status: Closed
  • Resolution: Cannot Reproduce
  • OS: linux_2.4
  • CPU: x86
  • Submitted: 2002-04-29
  • Updated: 2002-05-01
  • Resolved: 2002-05-01
Related Reports
Relates :  
JDK-4744936 - Can not drag and drop between Netscape and Sun Download Manager
Description
DnD operation can freeze Xserver. It's appeared on Linux/Gnome, Solaris, w2k with jdk1.4 (jdk1.4.0-build92). This combination freezes Xserver sure:
1. a modal dialog as drag source
2. another component (e.g. JList in JFrame)
3. the modal dialog is show in SwinUtilities.invokeLater
4. the cursor enters in a component during DnD
==> Xserver freezes.

See attached test, try run DnDFreezesTest on jdk1.3_03 --> w/o problems
try run it on jdk1.4-b92 --> described behavior!

Thanks for attention.
Comments
EVALUATION We should investigate this for hopper. ###@###.### 2002-04-29 Name: dsR10078 Date: 04/30/2002 This hang has the same cause as the one documented in 4633417. If a component has an associated drop target, it receives drag notifications when the mouse is dragged over it during a drag operation. The toolkit thread waits while the drop target listener registered with the drop target processes the drag notification to communicate its response to the drag source. If the component with an associated drop target is outside of the current modal hierarchy, the drag notification is filtered out and the drop target listener doesn't have a chance to process this notification, so the toolkit thread remains blocked forever. The fix for 4633417 resolves this problem. I reproduced this hang on 1.4.0-b92 and 1.4.1-b05 on Sparc/Solaris and WinNT and verified that the hang is not reproducible on 1.4.1-b08,b09 and b10. ###@###.### 2002-04-30 ======================================================================
30-04-2002