src/java.desktop/windows/classes/sun/awt/windows/WWindowPeer.java

*** 79,88 ****
--- 79,91 ----
       * Called (on the Toolkit thread) before the appropriate
       * WindowStateEvent is posted to the EventQueue.
       */
      private WindowListener windowListener;
  
+     private float scaleX;
+     private float scaleY;
+ 
      /**
       * Initialize JNI field IDs
       */
      private static native void initIDs();
      static {
*** 188,198 ****
              ((Window) target).setBackground(SystemColor.window);
          }
  
          // Express our interest in display changes
          GraphicsConfiguration gc = getGraphicsConfiguration();
!         ((Win32GraphicsDevice)gc.getDevice()).addDisplayChangedListener(this);
  
          initActiveWindowsTracking((Window)target);
  
          updateIconImages();
  
--- 191,204 ----
              ((Window) target).setBackground(SystemColor.window);
          }
  
          // Express our interest in display changes
          GraphicsConfiguration gc = getGraphicsConfiguration();
!         Win32GraphicsDevice gd = (Win32GraphicsDevice) gc.getDevice();
!         gd.addDisplayChangedListener(this);
!         scaleX = gd.getDefaultScaleX();
!         scaleY = gd.getDefaultScaleY();
  
          initActiveWindowsTracking((Window)target);
  
          updateIconImages();
  
*** 537,548 ****
--- 543,569 ----
              newDev.addDisplayChangedListener(this);
          }
  
          AWTAccessor.getComponentAccessor().
              setGraphicsConfiguration((Component)target, winGraphicsConfig);
+ 
+         float newScaleX = newDev.getDefaultScaleX();
+         float newScaleY = newDev.getDefaultScaleY();
+ 
+         if (scaleX != newScaleX || scaleY != newScaleY) {
+             Window win = (Window) target;
+             setBounds(rescale(win.getX(), scaleX, newScaleX),
+                       rescale(win.getY(), scaleY, newScaleY),
+                       win.getWidth(), win.getHeight(), SET_BOUNDS);
+             scaleX = newScaleX;
+             scaleY = newScaleY;
+         }
      }
  
+     private static int rescale(int position, float oldScale, float newScale) {
+         return Math.round(position * oldScale / newScale);
+     }
      /**
       * From the DisplayChangedListener interface.
       *
       * This method handles a display change - either when the display settings
       * are changed, or when the window has been dragged onto a different