src/macosx/classes/sun/awt/CGraphicsDevice.java

*** 28,37 ****
--- 28,38 ----
  import java.awt.GraphicsConfiguration;
  import java.awt.GraphicsDevice;
  import java.awt.Window;
  import java.awt.AWTPermission;
  import java.awt.DisplayMode;
+ import java.util.Objects;
  
  import sun.java2d.opengl.CGLGraphicsConfig;
  
  public final class CGraphicsDevice extends GraphicsDevice {
  
*** 120,135 ****
          }
  
          boolean fsSupported = isFullScreenSupported();
  
          if (fsSupported && old != null) {
!             // enter windowed mode (and restore original display mode)
!             exitFullScreenExclusive(old);
              if (originalMode != null) {
                  setDisplayMode(originalMode);
                  originalMode = null;
              }
          }
  
          super.setFullScreenWindow(w);
  
          if (fsSupported && w != null) {
--- 121,136 ----
          }
  
          boolean fsSupported = isFullScreenSupported();
  
          if (fsSupported && old != null) {
!             // restore original display mode and enter windowed mode.
              if (originalMode != null) {
                  setDisplayMode(originalMode);
                  originalMode = null;
              }
+             exitFullScreenExclusive(old);
          }
  
          super.setFullScreenWindow(w);
  
          if (fsSupported && w != null) {
*** 184,200 ****
      public boolean isDisplayChangeSupported() {
          return true;
      }
  
      @Override
!     public void setDisplayMode(DisplayMode dm) {
          if (dm == null) {
              throw new IllegalArgumentException("Invalid display mode");
          }
!         nativeSetDisplayMode(displayID, dm.getWidth(), dm.getHeight(), dm.getBitDepth(), dm.getRefreshRate());
!         if (isFullScreenSupported() && getFullScreenWindow() != null) {
!             getFullScreenWindow().setSize(dm.getWidth(), dm.getHeight());
          }
      }
  
      @Override
      public DisplayMode getDisplayMode() {
--- 185,208 ----
      public boolean isDisplayChangeSupported() {
          return true;
      }
  
      @Override
!     public void setDisplayMode(final DisplayMode dm) {
          if (dm == null) {
              throw new IllegalArgumentException("Invalid display mode");
          }
!         if (!Objects.equals(dm, getDisplayMode())) {
!             final Window w = getFullScreenWindow();
!             if (w != null) {
!                 exitFullScreenExclusive(w);
!             }
!             nativeSetDisplayMode(displayID, dm.getWidth(), dm.getHeight(),
!                                  dm.getBitDepth(), dm.getRefreshRate());
!             if (isFullScreenSupported() && w != null) {
!                 enterFullScreenExclusive(w);
!             }
          }
      }
  
      @Override
      public DisplayMode getDisplayMode() {