EVALUATION

The fix suggested is based on the fact that each AWT window that shouldn't be shown on the
taskbar has WS_POPUP style. For such windows we shouldn't set WS_EX_APPWINDOW style.
                                     

SUGGESTED FIX

src/windows/native/sun/windows/awt_PopupMenu.cpp
src/windows/native/sun/windows/awt_Window.cpp
src/windows/native/sun/windows/awt_Window.h


------- awt_PopupMenu.cpp -------
*** /tmp/sccs.UjaaMN	Tue Feb 21 18:22:25 2006
--- awt_PopupMenu.cpp	Tue Feb 21 16:42:10 2006
***************
*** 113,123 ****
              pt.y -= rctInsets.top;
  
              flags = TPM_LEFTALIGN | TPM_RIGHTBUTTON;
  
          } else {
-             ((AwtWindow*)awtOrigin)->SetFocusableWindow(TRUE); // for AwtWindow's focus hook
              ::SetForegroundWindow(awtOrigin->GetHWnd());
  
              flags = TPM_NONOTIFY | TPM_RIGHTALIGN | TPM_RIGHTBUTTON | TPM_BOTTOMALIGN;
          }
  
--- 113,122 ----


------- awt_Window.cpp -------
*** /tmp/sccs.staOTN	Tue Feb 21 18:22:26 2006
--- awt_Window.cpp	Tue Feb 21 18:11:27 2006
***************
*** 118,127 ****
--- 118,128 ----
  
      // what's the best initial value?
      m_screenNum = -1;
      ms_instanceCounter++;
      m_grabbed = FALSE;
+     m_isFocusableWindow = TRUE;
  
      if (AwtWindow::ms_instanceCounter == 1) {
          AwtWindow::ms_hCBTFilter =
              ::SetWindowsHookEx(WH_CBT, (HOOKPROC)AwtWindow::CBTFilter,
                                 0, AwtToolkit::MainThread());
***************
*** 1740,1759 ****
      
      PDATA pData;
      JNI_CHECK_PEER_GOTO(self, ret);
      window = (AwtWindow *)pData;
  
      if (IS_WIN2000) {
!         if (!isFocusableWindow) {
!             window->SetStyleEx(window->GetStyleEx() | WS_EX_APPWINDOW | AWT_WS_EX_NOACTIVATE);
          } else {
              window->SetStyleEx(window->GetStyleEx() & ~WS_EX_APPWINDOW & ~AWT_WS_EX_NOACTIVATE); 
          }
!     }
  
-     window->SetFocusableWindow(isFocusableWindow); 
- 
    ret:
      env->DeleteGlobalRef(self);
      delete sfws;
  }
  
--- 1741,1761 ----
      
      PDATA pData;
      JNI_CHECK_PEER_GOTO(self, ret);
      window = (AwtWindow *)pData;
  
+     window->m_isFocusableWindow = isFocusableWindow;
+ 
      if (IS_WIN2000) {
!         if (!window->m_isFocusableWindow) {
!             LONG isPopup = window->GetStyle() & WS_POPUP;
!             window->SetStyleEx(window->GetStyleEx() | (isPopup ? 0 : WS_EX_APPWINDOW) | AWT_WS_EX_NOACTIVATE);
          } else {
              window->SetStyleEx(window->GetStyleEx() & ~WS_EX_APPWINDOW & ~AWT_WS_EX_NOACTIVATE); 
          }
!     } 
  
    ret:
      env->DeleteGlobalRef(self);
      delete sfws;
  }
  

------- awt_Window.h -------
*** /tmp/sccs.JEaq1N	Tue Feb 21 18:22:27 2006
--- awt_Window.h	Tue Feb 21 18:11:34 2006
***************
*** 92,104 ****
      void SendComponentEvent(jint eventId);
      void SendWindowEvent(jint id, HWND opposite = NULL,
  			 jint oldState = 0, jint newState = 0);
  
      BOOL IsFocusableWindow();
-     INLINE void SetFocusableWindow(BOOL isFocusableWindow) {
-         m_isFocusableWindow = isFocusableWindow;
-     }
  
      /* some helper methods about blocking windows by modal dialogs */
      INLINE static HWND GetModalBlocker(HWND window) {
          return reinterpret_cast<HWND>(::GetProp(window, ModalBlockerProp));
      }
--- 92,101 ----
                                     

EVALUATION

This regression is caused by the fix for 5091224 (Non-focusable windows steal focus from desktop windows). In that fix an extended style WS_EX_APPWINDOW is added to every AWT toplevel window, and that leads to all the windows to appear on the taskbar.

If WS_EX_APPWINDOW style is simply removed, then all the non-focusable frames will disappear from the taskbar because of another style WS_EX_NOACTIVATE. So we need to track what toplevel is (Frame, Dialog, Window) and set WS_EX_APPWINDOW only for those that must be displayed on the taskbar: frames, ownerless dialogs, probably something else (need to be checked).