JBR-9698 Wayland: session auto-detection doesn't work with binary launcher

Use getRootPane()
.putClientProperty("wlawt.popup_position_unconstrained", Boolean.TRUE)
to enable unconstrained popup positioning.

src/hotspot/share/runtime/arguments.cpp

@@ -22,6 +22,10 @@
  *
  */
 
+#ifdef __linux
+#include <dlfcn.h>
+#endif
+
 #include "cds/aotLogging.hpp"
 #include "cds/cds_globals.hpp"
 #include "cds/cdsConfig.hpp"
@@ -3855,6 +3859,34 @@ void Arguments::set_compact_headers_flags() {
 #endif
 }
 
+#ifdef __linux
+static const char * get_toolkit_name() {
+  const char * toolkit_name = "XToolkit";
+  void* libwayland = dlopen(VERSIONED_JNI_LIB_NAME("wayland-client", "0"), RTLD_LAZY | RTLD_LOCAL);
+  if (!libwayland) {
+    // Fallback to any development version available on the system
+    libwayland = dlopen(JNI_LIB_NAME("wayland-client"), RTLD_LAZY | RTLD_LOCAL);
+  }
+  if (libwayland) {
+    typedef void* (*wl_display_connect_t)(const char*);
+    typedef void (*wl_display_disconnect_t)(void*);
+
+    wl_display_connect_t fp_wl_display_connect = (wl_display_connect_t) dlsym(libwayland, "wl_display_connect");
+    wl_display_disconnect_t fp_wl_display_disconnect = (wl_display_disconnect_t) dlsym(libwayland, "wl_display_disconnect");
+
+    if (fp_wl_display_connect && fp_wl_display_disconnect) {
+      void* display = fp_wl_display_connect(NULL);
+      if (display) {
+        toolkit_name = "WLToolkit";
+        fp_wl_display_disconnect(display);
+      }
+    }
+    dlclose(libwayland);
+  }
+  return toolkit_name;
+}
+#endif
+
 jint Arguments::apply_ergo() {
   // Set flags based on ergonomics.
   jint result = set_ergonomics_flags();
@@ -3925,6 +3957,17 @@ jint Arguments::apply_ergo() {
     FLAG_SET_DEFAULT(BytecodeVerificationRemote, true);
   }
 
+#ifdef __linux
+  // Replace -Dawt.toolkit.name=auto with either XToolkit (the default) or
+  // WLToolkit, if we are able to connect to the Wayland server.
+  const char* toolkit_name = PropertyList_get_value(_system_properties, "awt.toolkit.name");
+  if (toolkit_name && strcmp(toolkit_name, "auto") == 0) {
+    const char* toolkit_name = get_toolkit_name();
+    PropertyList_unique_add(&_system_properties, "awt.toolkit.name", toolkit_name,
+                            AddProperty, WriteableProperty, ExternalProperty);
+  }
+#endif
+
 #ifndef PRODUCT
   if (!LogVMOutput && FLAG_IS_DEFAULT(LogVMOutput)) {
     if (use_vm_log()) {

src/java.desktop/unix/classes/sun/awt/wl/FullFrameDecorationHelper.java

@@ -164,7 +164,7 @@ public abstract class FullFrameDecorationHelper extends FrameDecoration {
 
     @Override
     public void paint(Graphics g) {
-        assert isRepaintNeeded();
+        assert isRepaintNeeded() : "paint() called when no repaint needed";
 
         int width = peer.getWidth();
         int height = peer.getHeight();
@@ -196,7 +196,7 @@ public abstract class FullFrameDecorationHelper extends FrameDecoration {
     }
 
     private boolean isSignificantDrag(Point p) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         Objects.requireNonNull(p);
         return pressedLocation != null && isSignificantDragDistance(pressedLocation, p);
@@ -208,7 +208,7 @@ public abstract class FullFrameDecorationHelper extends FrameDecoration {
 
     @Override
     boolean processMouseEvent(MouseEvent e) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (super.processMouseEvent(e)) return true;
 
@@ -326,7 +326,7 @@ public abstract class FullFrameDecorationHelper extends FrameDecoration {
         }
 
         private boolean processMouseEvent(MouseEvent e) {
-            assert EventQueue.isDispatchThread();
+            assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
             Rectangle buttonBounds = bounds.get();
             boolean ourLocation = buttonBounds != null && e.getID() != MouseEvent.MOUSE_EXITED &&

src/java.desktop/unix/classes/sun/awt/wl/GtkFrameDecoration.java

@@ -68,7 +68,7 @@ public class GtkFrameDecoration extends FullFrameDecorationHelper {
     public GtkFrameDecoration(WLDecoratedPeer peer, boolean showMinimize, boolean showMaximize) {
         super(peer, showMinimize, showMaximize);
         nativePtr = nativeCreateDecoration(showMinimize, showMaximize, isDarkTheme());
-        assert nativePtr != 0;
+        assert nativePtr != 0 : "Failed to create the native part of the decoration";
         int t = nativeGetIntProperty(nativePtr, "gtk-dnd-drag-threshold");
         dndThreshold = t > 0 ? t : 4;
     }
@@ -87,8 +87,8 @@ public class GtkFrameDecoration extends FullFrameDecorationHelper {
         int width = peer.getWidth();
         int height = titleBarHeight;
 
-        assert width >= titleBarMinWidth;
-        assert peer.getHeight() >= titleBarHeight;
+        assert width >= titleBarMinWidth : "The frame width is too small to display the title bar";
+        assert peer.getHeight() >= titleBarHeight : "The frame height is too small to display the title bar";
 
         double scale = ((WLGraphicsConfig) peer.getGraphicsConfiguration()).getEffectiveScale();
         g2d.setBackground(new Color(0, true));

src/java.desktop/unix/classes/sun/awt/wl/ServerSideFrameDecoration.java

@@ -96,7 +96,7 @@ public class ServerSideFrameDecoration extends FrameDecoration {
     @Override
     public void dispose() {
         // Native resources must have been already disposed when the window was hidden
-        assert nativeDecorPtr == 0;
+        assert nativeDecorPtr == 0 : "Native resources must have been already disposed";
     }
 
     private native long createToplevelDecorationImpl(long nativeFramePtr);

src/java.desktop/unix/classes/sun/awt/wl/WLComponentPeer.java

@@ -88,6 +88,8 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
     private static final PlatformLogger focusLog = PlatformLogger.getLogger("sun.awt.wl.focus.WLComponentPeer");
     private static final PlatformLogger popupLog = PlatformLogger.getLogger("sun.awt.wl.popup.WLComponentPeer");
 
+    public static final String POPUP_POSITION_UNCONSTRAINED_CLIENT_PROPERTY = "wlawt.popup_position_unconstrained";
+
     protected static final int MINIMUM_WIDTH = 1;
     protected static final int MINIMUM_HEIGHT = 1;
 
@@ -318,7 +320,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         if (what.getMinY() >= where.getMaxY()) {
             what.y -= what.getMinY() - where.getMaxY();
         }
-        assert what.intersects(where);
+        assert what.intersects(where) : String.format("Failed to move %s to overlap %s", what, where);
     }
 
     Point nativeLocationForPopup(Window popup, Component popupParent, Window toplevel) {
@@ -351,6 +353,18 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         return popupBounds.getLocation();
     }
 
+    private boolean isPopupPositionUnconstrained() {
+        if (SunToolkit.isInstanceOf(target, "javax.swing.RootPaneContainer")) {
+            javax.swing.JRootPane rootpane = ((javax.swing.RootPaneContainer) target).getRootPane();
+            Object prop = rootpane.getClientProperty(POPUP_POSITION_UNCONSTRAINED_CLIENT_PROPERTY);
+            if (prop instanceof Boolean booleanProp) {
+                return booleanProp;
+            }
+        }
+
+        return false;
+    }
+
     protected void wlSetVisible(boolean v) {
         // TODO: this whole method should be moved to WLWindowPeer
         synchronized (getStateLock()) {
@@ -370,9 +384,10 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
                     : Frame.NORMAL;
             boolean isMaximized = (state & Frame.MAXIMIZED_BOTH) == Frame.MAXIMIZED_BOTH;
             boolean isMinimized = (state & Frame.ICONIFIED) == Frame.ICONIFIED;
+            boolean isUnconstrained = isPopupPositionUnconstrained();
 
             performLocked(() -> {
-                assert wlSurface == null;
+                assert wlSurface == null : "Invisible window already has a Wayland surface attached";
                 wlSurface = new WLMainSurface((WLWindowPeer) this);
                 long wlSurfacePtr = wlSurface.getWlSurfacePtr();
                 if (isWlPopup) {
@@ -381,7 +396,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
                     Window toplevel = getToplevelFor(popupParent);
                     Point nativeLocation = nativeLocationForPopup(popup, popupParent, toplevel);
                     nativeCreatePopup(nativePtr, getNativePtrFor(toplevel), wlSurfacePtr,
-                            thisWidth, thisHeight, nativeLocation.x, nativeLocation.y);
+                            thisWidth, thisHeight, nativeLocation.x, nativeLocation.y, isUnconstrained);
                 } else {
                     nativeCreateWindow(nativePtr, getParentNativePtr(target), wlSurfacePtr,
                             isModal, isMaximized, isMinimized, title, WLToolkit.getApplicationID());
@@ -462,7 +477,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
 
     @Override
     public void updateSurfaceSize() {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         // Note: must be called after a buffer of proper size has been attached to the surface,
         // but the surface has not yet been committed. Otherwise, the sizes will get out of sync,
         // which may result in visual artifacts.
@@ -500,7 +515,8 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
             final Component popupParent = AWTAccessor.getWindowAccessor().getPopupParent(popup);
             final Window toplevel = getToplevelFor(popupParent);
             Point nativeLocation = nativeLocationForPopup(popup, popupParent, toplevel);
-            nativeRepositionWLPopup(nativePtr, surfaceWidth, surfaceHeight, nativeLocation.x, nativeLocation.y);
+            boolean isUnconstrained = isPopupPositionUnconstrained();
+            nativeRepositionWLPopup(nativePtr, surfaceWidth, surfaceHeight, nativeLocation.x, nativeLocation.y, isUnconstrained);
         }
     }
 
@@ -894,7 +910,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         //  a button press, key press, or touch down event."
         // So 'serial' must appertain to such an event.
 
-        assert serial != 0;
+        assert serial != 0 : "The serial number of the event requesting the window menu must be non-zero";
 
         int xNative = javaUnitsToSurfaceUnits(x);
         int yNative = javaUnitsToSurfaceUnits(y);
@@ -954,7 +970,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         WLToolkit.targetDisposedPeer(target, this);
 
         performLocked(() -> {
-            assert !isVisible();
+            assert !isVisible() : "Disposed window must have been already hidden";
 
             nativeDisposeFrame(nativePtr);
             nativePtr = 0;
@@ -1150,12 +1166,14 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
                                                 String title, String appID);
 
     protected native void nativeCreatePopup(long ptr, long parentPtr, long wlSurfacePtr,
-                                              int width, int height,
-                                              int offsetX, int offsetY);
+                                            int width, int height,
+                                            int offsetX, int offsetY,
+                                            boolean isUnconstrained);
 
     protected native void nativeRepositionWLPopup(long ptr,
                                                   int width, int height,
-                                                  int offsetX, int offsetY);
+                                                  int offsetX, int offsetY,
+                                                  boolean isUnconstrained);
     protected native void nativeHideFrame(long ptr);
 
     protected native void nativeDisposeFrame(long ptr);
@@ -1355,7 +1373,8 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
             }
 
             if (verticalMWERoundRotations != 0 || verticalMWEPreciseRotations != 0) {
-                assert(verticalMWEScrollAmount > 0);
+                assert verticalMWEScrollAmount > 0
+                        : String.format("Vertical scrolling event has negative scroll amount: %d", verticalMWEScrollAmount);
 
                 final MouseEvent mouseEvent = new MouseWheelEvent(getTarget(),
                         MouseEvent.MOUSE_WHEEL,
@@ -1374,7 +1393,8 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
             }
 
             if (horizontalMWERoundRotations != 0 || horizontalMWEPreciseRotations != 0) {
-                assert(horizontalMWEScrollAmount > 0);
+                assert horizontalMWEScrollAmount > 0
+                        : String.format("Horizontal scrolling event has negative scroll amount: %d", horizontalMWEScrollAmount);;
 
                 final MouseEvent mouseEvent = new MouseWheelEvent(getTarget(),
                         MouseEvent.MOUSE_WHEEL,
@@ -1585,7 +1605,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         // "This request must be used in response to some sort of user action like a button press,
         //  key press, or touch down event. The passed serial is used to determine the type
         //  of interactive move (touch, pointer, etc)."
-        assert serial != 0;
+        assert serial != 0 : "The serial number of the event requesting the drag must be non-zero";
 
         performLocked(() -> nativeStartDrag(serial, nativePtr));
     }
@@ -1594,7 +1614,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         // "This request must be used in response to some sort of user action like a button press,
         //  key press, or touch down event. The passed serial is used to determine the type
         //  of interactive resize (touch, pointer, etc)."
-        assert serial != 0;
+        assert serial != 0 : "The serial number of the event requesting the resize must be non-zero";
 
         performLocked(() -> nativeStartResize(serial, nativePtr, edges));
     }
@@ -1674,7 +1694,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
 
     void notifyConfigured(int newSurfaceX, int newSurfaceY, int newSurfaceWidth, int newSurfaceHeight,
                           boolean active, boolean maximized, boolean fullscreen) {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
         // NB: The width and height, as well as X and Y arguments, specify the size and the location
         //     of the window in surface-local coordinates.
@@ -1755,12 +1775,12 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
     }
 
     void notifyPopupDone() {
-        assert(targetIsWlPopup());
+        assert targetIsWlPopup() : "This method must be invoked only for popups";
         target.setVisible(false);
     }
 
     void checkIfOnNewScreen() {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
         if (wlSurface == null) return;
         final WLGraphicsDevice newDevice = wlSurface.getGraphicsDevice();
@@ -2005,7 +2025,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
 
         @Override
         public void updateSurfaceSize() {
-            assert SunToolkit.isAWTLockHeldByCurrentThread();
+            assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
             shadowSurface.updateSurfaceSize(shadowWlSize.getSurfaceWidth(), shadowWlSize.getSurfaceHeight());
         }
@@ -2017,8 +2037,8 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         }
 
         public void createSurface() {
-            assert shadowSurface == null;
-            assert SunToolkit.isAWTLockHeldByCurrentThread();
+            assert shadowSurface == null : "The shadow surface must not be created twice";
+            assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
             int shadowOffset = -javaUnitsToSurfaceUnits(shadowSize);
             shadowSurface = new WLSubSurface(wlSurface, shadowOffset, shadowOffset);
@@ -2026,13 +2046,13 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
 
         public void commitSurface() {
             assert shadowSurface != null;
-            assert SunToolkit.isAWTLockHeldByCurrentThread();
+            assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
             shadowSurface.commit();
         }
 
         public void dispose() {
-            assert SunToolkit.isAWTLockHeldByCurrentThread();
+            assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
             if (shadowSurface != null) {
                 shadowSurface.dispose();
@@ -2047,7 +2067,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         }
 
         public void hide() {
-            assert SunToolkit.isAWTLockHeldByCurrentThread();
+            assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
             if (shadowSurface != null) {
                 shadowSurface.dispose();
@@ -2056,7 +2076,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         }
 
         public void updateSurfaceData() {
-            assert SunToolkit.isAWTLockHeldByCurrentThread();
+            assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
             needsRepaint = true;
             SurfaceData.convertTo(WLSurfaceDataExt.class, shadowSurfaceData).revalidate(
@@ -2064,7 +2084,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
         }
 
         public void paint() {
-            assert SunToolkit.isAWTLockHeldByCurrentThread();
+            assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
             if (!needsRepaint) {
                 return;
@@ -2090,7 +2110,7 @@ public class WLComponentPeer implements ComponentPeer, WLSurfaceSizeListener {
 
         public void notifyConfigured(boolean active, boolean maximized, boolean fullscreen) {
             assert shadowSurface != null;
-            assert SunToolkit.isAWTLockHeldByCurrentThread();
+            assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
             needsRepaint |= active ^ isActive;
 

src/java.desktop/unix/classes/sun/awt/wl/WLDataOffer.java

@@ -77,7 +77,8 @@ public class WLDataOffer {
 
         fd = openReceivePipe(nativePtr, mime);
 
-        assert(fd != -1); // Otherwise an exception should be thrown from native code
+        // Otherwise an exception should be thrown from native code
+        assert fd != -1 : "An invalid file descriptor received from the native code";
 
         FileDescriptor javaFD = new FileDescriptor();
         jdk.internal.access.SharedSecrets.getJavaIOFileDescriptorAccess().set(javaFD, fd);

src/java.desktop/unix/classes/sun/awt/wl/WLDataSource.java

@@ -53,7 +53,7 @@ public class WLDataSource {
         var wlDataTransferer = (WLDataTransferer) WLDataTransferer.getInstance();
 
         nativePtr = initNative(dataDevice.getNativePtr(), protocol);
-        assert nativePtr != 0; // should've already thrown in native
+        assert nativePtr != 0 : "Failed to initialize the native part of the source"; // should've already thrown in native
         this.data = data;
 
         try {

src/java.desktop/unix/classes/sun/awt/wl/WLGraphicsDevice.java

@@ -128,10 +128,10 @@ public class WLGraphicsDevice extends GraphicsDevice {
                              int widthLogical, int heightLogical,
                              int widthMm, int heightMm,
                              int displayScale) {
-        assert width > 0 && height > 0;
-        assert widthLogical > 0 && heightLogical > 0;
-        assert widthMm > 0 && heightMm > 0;
-        assert displayScale > 0;
+        assert width > 0 && height > 0 : String.format("Invalid device size: %dx%d", width, height);
+        assert widthLogical > 0 && heightLogical > 0 : String.format("Invalid logical device size: %dx%d", widthLogical, heightLogical);
+        assert widthMm > 0 && heightMm > 0 : String.format("Invalid physical device size: %dx%d", widthMm, heightMm);
+        assert displayScale > 0 : String.format("Invalid display scale: %d", displayScale);
 
         this.wlID = id;
         this.name = name;
@@ -176,10 +176,10 @@ public class WLGraphicsDevice extends GraphicsDevice {
                              int widthLogical, int heightLogical,
                              int widthMm, int heightMm,
                              int scale) {
-        assert width > 0 && height > 0;
-        assert widthLogical > 0 && heightLogical > 0;
-        assert widthMm > 0 && heightMm > 0;
-        assert scale > 0;
+        assert width > 0 && height > 0 : String.format("Invalid device size: %dx%d", width, height);
+        assert widthLogical > 0 && heightLogical > 0 : String.format("Invalid logical device size: %dx%d", widthLogical, heightLogical);
+        assert widthMm > 0 && heightMm > 0 : String.format("Invalid physical device size: %dx%d", widthMm, heightMm);
+        assert scale > 0 : String.format("Invalid display scale: %d", scale);
 
         this.name = name;
         this.x = x;

src/java.desktop/unix/classes/sun/awt/wl/WLGraphicsEnvironment.java

@@ -133,8 +133,16 @@ public class WLGraphicsEnvironment extends SunGraphicsEnvironment implements HiD
         }
 
         // Logical size comes from an optional protocol, so take the data from the main one, if absent
-        if (widthLogical == 0) widthLogical = width;
-        if (heightLogical == 0) heightLogical = height;
+        if (widthLogical <= 0) widthLogical = width;
+        if (heightLogical <= 0) heightLogical = height;
+
+        // Physical size may be absent for virtual outputs.
+        if (widthMm <= 0 || heightMm <= 0) {
+            // Assume a 92 DPI display
+            widthMm = (int) Math.ceil(25.4 * width / 92.0);
+            heightMm = (int) Math.ceil(25.4 * height / 92.0);
+        }
+
         String humanID = deviceNameFrom(name, make, model);
 
         WLGraphicsDevice gd = deviceWithID(wlID);

src/java.desktop/unix/classes/sun/awt/wl/WLInputState.java

@@ -242,7 +242,9 @@ record WLInputState(WLPointerEvent eventWithSurface,
                                                         WLPointerEvent newEventWithTimestamp,
                                                         WLPointerEvent newEventWithPosition) {
         if (pointerEvent.hasButtonEvent() && pointerEvent.getIsButtonPressed() && newEventWithSurface != null) {
-            assert newEventWithTimestamp != null && newEventWithPosition != null;
+            assert newEventWithTimestamp != null && newEventWithPosition != null
+                    : "Events with timestamp and position are both required to be present";
+
             int clickCount = 1;
             final boolean pressedSameButton = pointerButtonPressedEvent != null
                     && pointerEvent.getButtonCode() == pointerButtonPressedEvent.linuxCode;

src/java.desktop/unix/classes/sun/awt/wl/WLKeyboard.java

@@ -48,7 +48,7 @@ class WLKeyboard {
         // called from native code
         void setRepeatInfo(int charsPerSecond, int delayMillis) {
             // this function receives (0, 0) when key repeat is disabled
-            assert EventQueue.isDispatchThread();
+            assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
             this.delayBeforeRepeatMillis = delayMillis;
             if (charsPerSecond > 0) {
                 this.delayBetweenRepeatMillis = (int) (1000.0 / charsPerSecond);
@@ -64,7 +64,7 @@ class WLKeyboard {
         }
 
         void cancelRepeat() {
-            assert EventQueue.isDispatchThread();
+            assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
             if (currentRepeatTask != null) {
                 currentRepeatTask.cancel();
                 currentRepeatTask = null;
@@ -74,7 +74,7 @@ class WLKeyboard {
 
         // called from native code
         void stopRepeat(int keycode) {
-            assert EventQueue.isDispatchThread();
+            assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
             if (currentRepeatKeycode == keycode) {
                 cancelRepeat();
             }
@@ -82,7 +82,7 @@ class WLKeyboard {
 
         // called from native code
         void startRepeat(long serial, long timestamp, int keycode) {
-            assert EventQueue.isDispatchThread();
+            assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
             cancelRepeat();
             if (keycode == 0 || !isRepeatEnabled()) {
                 return;
@@ -123,7 +123,7 @@ class WLKeyboard {
     public native boolean isNumLockPressed();
 
     public void onLostFocus() {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
         keyRepeatManager.cancelRepeat();
         cancelCompose();
     }

src/java.desktop/unix/classes/sun/awt/wl/WLMainSurface.java

@@ -91,7 +91,7 @@ public class WLMainSurface extends WLSurface {
     }
 
     public void activateByAnotherSurface(long serial, long activatingSurfacePtr) {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         nativeActivate(getNativePtr(), serial, activatingSurfacePtr);

src/java.desktop/unix/classes/sun/awt/wl/WLPointerEvent.java

@@ -217,37 +217,37 @@ class WLPointerEvent {
     }
 
     public long getSurface() {
-        assert hasSurface();
+        assert hasSurface() : "The event must have a valid surface";
         return surface;
     }
 
     public long getSerial() {
-        assert hasSerial();
+        assert hasSerial() : "The event must have a valid serial";
         return serial;
     }
 
     public long getTimestamp() {
-        assert hasTimestamp();
+        assert hasTimestamp() : "The event must have a valid timestamp";
         return timestamp;
     }
 
     public int getSurfaceX() {
-        assert hasCoordinates();
+        assert hasCoordinates() : "The event must have valid coordinates";
         return surface_x;
     }
 
     public int getSurfaceY() {
-        assert hasCoordinates();
+        assert hasCoordinates() : "The event must have valid coordinates";
         return surface_y;
     }
 
     public int getButtonCode() {
-        assert hasButtonEvent();
+        assert hasButtonEvent() : "Must have a button event to get the button code";
         return buttonCode;
     }
 
     public boolean getIsButtonPressed() {
-        assert hasButtonEvent();
+        assert hasButtonEvent() : "Must have a button event to get the button state";
         return isButtonPressed;
     }
 
@@ -270,12 +270,12 @@ class WLPointerEvent {
     }
 
     public double getXAxisVectorValue() {
-        assert xAxisHasVectorValue();
+        assert xAxisHasVectorValue() : "Must have an X axis vector value";
         return xAxis_vectorValue;
     }
 
     public int getXAxisSteps120Value() {
-        assert xAxisHasSteps120Value();
+        assert xAxisHasSteps120Value() : "Must have an X axis steps120 value";
         return xAxis_steps120Value;
     }
 
@@ -298,12 +298,12 @@ class WLPointerEvent {
     }
 
     public double getYAxisVectorValue() {
-        assert yAxisHasVectorValue();
+        assert yAxisHasVectorValue()  : "Must have an Y axis vector value";
         return yAxis_vectorValue;
     }
 
     public int getYAxisSteps120Value() {
-        assert yAxisHasSteps120Value();
+        assert yAxisHasSteps120Value(): "Must have an Y axis steps120 value";
         return yAxis_steps120Value;
     }
 

src/java.desktop/unix/classes/sun/awt/wl/WLRobotPeer.java

@@ -171,7 +171,7 @@ public class WLRobotPeer implements RobotPeer {
     static Point getLocationOfWLSurface(WLSurface wlSurface) {
         checkExtensionPresent();
 
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
         final long wlSurfacePtr = wlSurface.getWlSurfacePtr();
         // The native implementation allows for just one such request at a time

src/java.desktop/unix/classes/sun/awt/wl/WLSurface.java

@@ -57,7 +57,7 @@ public class WLSurface {
     }
 
     public void dispose() {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
 
         if (isValid) {
             hide();
@@ -67,7 +67,7 @@ public class WLSurface {
     }
 
     public void hide() {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         if (surfaceData == null) return;
@@ -85,14 +85,14 @@ public class WLSurface {
     }
 
     public boolean hasSurfaceData() {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         return surfaceData != null;
     }
 
     public void associateWithSurfaceData(SurfaceData data) {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         Objects.requireNonNull(data);
         assertIsValid();
 
@@ -103,7 +103,7 @@ public class WLSurface {
     }
 
     public void commit() {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         nativeCommitWlSurface(nativePtr);
@@ -115,28 +115,28 @@ public class WLSurface {
      * @return a pointer to wl_surface native object
      */
     public long getWlSurfacePtr() {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         return wlSurfacePtr;
     }
 
     protected long getNativePtr() {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         return nativePtr;
     }
 
     public void setSize(int width, int height) {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         nativeSetSize(nativePtr, width, height);
     }
 
     public void setOpaqueRegion(int x, int y, int width, int height) {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         nativeSetOpaqueRegion(nativePtr, x, y, width, height);
@@ -151,7 +151,7 @@ public class WLSurface {
     }
 
     public void updateSurfaceSize(int surfaceWidth, int surfaceHeight) {
-        assert SunToolkit.isAWTLockHeldByCurrentThread();
+        assert SunToolkit.isAWTLockHeldByCurrentThread() : "This method must be invoked while holding the AWT lock";
         assertIsValid();
 
         setSize(surfaceWidth, surfaceHeight);

src/java.desktop/unix/classes/sun/awt/wl/WLToolkit.java

@@ -331,7 +331,7 @@ public class WLToolkit extends UNIXToolkit implements Runnable {
 
     private static void dispatchPointerEvent(WLPointerEvent e) {
         // Invoked from the native code
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (log.isLoggable(PlatformLogger.Level.FINE)) log.fine("dispatchPointerEvent: " + e);
 
@@ -362,7 +362,7 @@ public class WLToolkit extends UNIXToolkit implements Runnable {
                                                  char keyChar,
                                                  int modifiers) {
         // Invoked from the native code
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         inputState = inputState.updatedFromKeyEvent(serial);
 
@@ -425,14 +425,14 @@ public class WLToolkit extends UNIXToolkit implements Runnable {
     }
 
     private static void dispatchKeyboardModifiersEvent(long serial) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
         inputState = inputState.updatedFromKeyboardModifiersEvent(serial, keyboard.getModifiers());
         WLDropTargetContextPeer.getInstance().handleModifiersUpdate();
     }
 
     private static void dispatchKeyboardEnterEvent(long serial, long surfacePtr) {
         // Invoked from the native code
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (logKeys.isLoggable(PlatformLogger.Level.FINE)) {
             logKeys.fine("dispatchKeyboardEnterEvent: " + serial + ", surface 0x"
@@ -461,7 +461,7 @@ public class WLToolkit extends UNIXToolkit implements Runnable {
 
     private static void dispatchKeyboardLeaveEvent(long serial, long surfacePtr) {
         // Invoked from the native code
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (logKeys.isLoggable(PlatformLogger.Level.FINE)) {
             logKeys.fine("dispatchKeyboardLeaveEvent: " + serial + ", surface 0x"

src/java.desktop/unix/classes/sun/awt/wl/im/text_input_unstable_v3/ClientComponentCaretPositionTracker.java

@@ -67,7 +67,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
 
 
     public void startTracking(final Component component) {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (log.isLoggable(PlatformLogger.Level.FINER)) {
             log.finer(
@@ -108,7 +108,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
     }
 
     public void stopTrackingCurrentComponent() {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (log.isLoggable(PlatformLogger.Level.FINER)) {
             log.finer(String.format("stopTrackingCurrentComponent(): this=%s.", this), new Throwable("Stacktrace"));
@@ -160,7 +160,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
     }
 
     public Component getTrackedComponentIfTracking() {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         final Component trackedComponentStrong;
         if (trackedComponent == null) {
@@ -188,7 +188,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
 
 
     public void deferUpdates() {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (log.isLoggable(PlatformLogger.Level.FINER)) {
             log.finer(String.format("deferUpdates(): this=%s.", this), new Throwable("Stacktrace"));
@@ -198,7 +198,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
     }
 
     public void resumeUpdates(final boolean discardDeferredUpdates) {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (log.isLoggable(PlatformLogger.Level.FINER)) {
             log.finer(String.format("resumeUpdates(%b): this=%s.", discardDeferredUpdates, this), new Throwable("Stacktrace"));
@@ -215,7 +215,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
     }
 
     public boolean areUpdatesDeferred() {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         return updatesAreDeferred;
     }
@@ -225,7 +225,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
 
     /** This method is intended to be called from the owning IM's {@link java.awt.im.spi.InputMethod#dispatchEvent(AWTEvent)}. */
     public void onIMDispatchEvent(AWTEvent event) {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (log.isLoggable(PlatformLogger.Level.FINER)) {
             log.finer("onIMDispatchEvent(event={0}): this={1}.", event, this);
@@ -254,7 +254,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
 
     /** This method is intended to be called from the owning IM's {@link java.awt.im.spi.InputMethod#notifyClientWindowChange(Rectangle)}. */
     public void onIMNotifyClientWindowChange(Rectangle location) {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (log.isLoggable(PlatformLogger.Level.FINER)) {
             log.finer("onIMNotifyClientWindowChange(location={0}): this={1}.", location, this);
@@ -333,7 +333,7 @@ class ClientComponentCaretPositionTracker implements ComponentListener, CaretLis
 
 
     private WLInputMethodZwpTextInputV3 getOwnerIm() {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         final WLInputMethodZwpTextInputV3 thisImStrong;
         if (this.im == null) {

src/java.desktop/unix/classes/sun/awt/wl/im/text_input_unstable_v3/InputContextState.java

@@ -40,7 +40,7 @@ final class InputContextState {
 
 
     public InputContextState(long nativeContextPtr) {
-        assert(nativeContextPtr != 0);
+        assert nativeContextPtr != 0 : "Cannot create an input context from a NULL pointer";
 
         this.nativeContextPtr = nativeContextPtr;
     }

src/java.desktop/unix/classes/sun/awt/wl/im/text_input_unstable_v3/JavaPreeditString.java

@@ -82,8 +82,8 @@ record JavaPreeditString(String text, int cursorBeginCodeUnit, int cursorEndCode
         }
 
         if (resultText == null) {
-            assert(fixedCursorBeginUtf8Byte == 0);
-            assert(fixedCursorEndUtf8Byte == 0);
+            assert fixedCursorBeginUtf8Byte == 0 : "Cursor begin byte must be zero for an empty string";
+            assert fixedCursorEndUtf8Byte == 0 : "Cursor end byte must be zero for an empty string";
 
             return JavaPreeditString.EMPTY;
         }

src/java.desktop/unix/classes/sun/awt/wl/im/text_input_unstable_v3/WLInputMethodDescriptorZwpTextInputV3.java

@@ -71,7 +71,7 @@ public final class WLInputMethodDescriptorZwpTextInputV3 implements InputMethodD
 
     @Override
     public String getInputMethodDisplayName(Locale inputLocale, Locale displayLanguage) {
-        assert isAvailableOnPlatform();
+        assert isAvailableOnPlatform() : "IM must be available on the platform";
 
         // This is how it's implemented in all other Toolkits.
         //
@@ -183,7 +183,7 @@ public final class WLInputMethodDescriptorZwpTextInputV3 implements InputMethodD
 
 
     private WLInputMethodDescriptorZwpTextInputV3() {
-        assert isAvailableOnPlatform();
+        assert isAvailableOnPlatform() : "IM must be available on the platform";
 
         initAndGetToolkitStartupLocale();
     }

src/java.desktop/unix/classes/sun/awt/wl/im/text_input_unstable_v3/WLInputMethodZwpTextInputV3.java

@@ -243,7 +243,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
         }
 
         // "The method is only called when the input method is inactive."
-        assert(this.awtActivationStatus != AWTActivationStatus.ACTIVATED);
+        assert this.awtActivationStatus != AWTActivationStatus.ACTIVATED : "The method is called when the IM is active";
 
         // The protocol doesn't provide a separate method for hiding the IM window(s),
         //   but this effect can be achieved by disabling the native context.
@@ -259,7 +259,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
         }
 
         // "The method is only called when the input method is inactive."
-        assert(this.awtActivationStatus != AWTActivationStatus.ACTIVATED);
+        assert this.awtActivationStatus != AWTActivationStatus.ACTIVATED : "The method is called when the IM is active";
 
         wlDisableContextNow();
     }
@@ -374,10 +374,10 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
     /* AWT-side methods section */
 
     private static void awtFillWlContentTypeOf(Component component, OutgoingChanges out) {
-        assert(component != null);
-        assert(out != null);
+        assert component != null : "Component must not be null";
+        assert out != null : "OutgoingChanges must not be null";
 
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         // TODO: there's no dedicated AWT/Swing API for that, but we can make a few guesses, e.g.
         //       (component instanceof JPasswordField) ? ContentPurpose.PASSWORD
@@ -389,7 +389,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
      *          compatible with {@code zwp_text_input_v3::set_cursor_rectangle} API;
      */
     private static Rectangle awtGetWlCursorRectangleOf(Component component) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         Rectangle result = null;
 
@@ -434,7 +434,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
      * @throws IllegalArgumentException if {@code visibleComponent} is {@code null} or isn't showing on the screen.
      */
     private static Rectangle awtGetCaretOf(Component visibleComponent) {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (!Objects.requireNonNull(visibleComponent, "visibleComponent").isShowing()) {
             throw new IllegalArgumentException("visibleComponent must be showing");
@@ -474,7 +474,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
     }
 
     private static Rectangle awtGetVisibleRectOf(final Component component) {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (component instanceof javax.swing.JComponent jComponent) {
             return jComponent.getVisibleRect();
@@ -488,7 +488,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
      *         or {@code null} if the rectangle couldn't be determined.
      */
     private static Rectangle awtConvertRectOnComponentToRectOnWlSurface(Component component, Rectangle rectOnComponent) {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         Objects.requireNonNull(component, "component");
 
@@ -536,7 +536,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
      *         or its closest ancestor meeting these requirements.
      */
     private static Window awtGetWlSurfaceComponentOf(Component component) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         return WLComponentPeer.getToplevelFor(component);
     }
@@ -557,8 +557,8 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
             log.finer("awtPostIMESafely(preeditString={0}, commitString={1}): this={2}.", preeditString, commitString, this);
         }
 
-        assert(preeditString != null);
-        assert(commitString != null);
+        assert preeditString != null : "Pre-edit string must be present";
+        assert commitString != null : "Commit string must be present";
 
         try {
             if (awtActivationStatus != AWTActivationStatus.ACTIVATED) {
@@ -769,8 +769,8 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
             specialPreeditHighlightingBegin = swapTemp;
         }
 
-        assert(specialPreeditHighlightingBegin >= 0);
-        assert(specialPreeditHighlightingEnd <= preeditTextLength);
+        assert specialPreeditHighlightingBegin >= 0 : "specialPreeditHighlightingBegin is invalid";
+        assert specialPreeditHighlightingEnd <= preeditTextLength : "specialPreeditHighlightingEnd is out of range";
 
         //    v
         // |BASIC+SPECIAL...|
@@ -827,10 +827,10 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
     // The methods in this section implement the core logic of working with the "text-input-unstable-v3" protocol.
 
     private void wlInitializeContext() throws AWTException {
-        assert(wlInputContextState == null);
-        assert(wlPendingChanges == null);
-        assert(wlBeingCommittedChanges == null);
-        assert(wlIncomingChanges == null);
+        assert wlInputContextState == null : "Must not initialize input context twice";
+        assert wlPendingChanges == null : "Must not initialize pending changes twice";
+        assert wlBeingCommittedChanges == null : "Must not initialize being-committed changes twice";
+        assert wlIncomingChanges == null : "Must not initialize incoming changes twice";
 
         long nativeCtxPtr = 0;
 
@@ -878,7 +878,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
      *   followed by a {@code zwp_text_input_v3::commit} request.
      */
     private void wlSendPendingChangesNow() {
-        assert(wlCanSendChangesNow());
+        assert wlCanSendChangesNow() : "Must be able to send pending changes now";
 
         final OutgoingChanges changesToSend = wlPendingChanges;
         wlPendingChanges = null;
@@ -997,7 +997,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
             throw new IllegalStateException("Attempt to enable an input context which hasn't entered any surface");
         }
 
-        assert(wlContextCanBeEnabledNow());
+        assert wlContextCanBeEnabledNow() : "Can't enable InputContext";
 
         // This way we guarantee the context won't accidentally get disabled because such a change has been scheduled earlier.
         // Anyway we consider any previously scheduled changes outdated because an 'enable' request is supposed to
@@ -1029,7 +1029,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
         awtFillWlContentTypeOf(getClientComponent(), changeSet);
 
         wlScheduleContextNewChanges(changeSet);
-        assert(wlPendingChanges != null);
+        assert wlPendingChanges != null : "Must have non-empty pending changes";
 
         // Pretending there are no committed, but not applied yet changes, so that wlCanSendChangesNow() is true.
         // We can do that because the assumption #1 and because any previously committed changes get lost when a
@@ -1038,7 +1038,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
         //    set_surrounding_text, set_text_change_cause, set_content_type, and set_cursor_rectangle requests [...]"
         wlBeingCommittedChanges = null;
 
-        assert(wlCanSendChangesNow());
+        assert wlCanSendChangesNow() : "Must be able to send pending changes now";
         wlSendPendingChangesNow();
 
         // See the assumption #2 above.
@@ -1103,10 +1103,10 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
             }
         }
 
-        assert(wlInputContextState.getCurrentWlSurfacePtr() != 0);
+        assert wlInputContextState.getCurrentWlSurfacePtr() != 0 : "InputContext must have a valid current surface pointer";
 
         wlScheduleContextNewChanges(new OutgoingChanges().setEnabledState(false));
-        assert(wlPendingChanges != null);
+        assert wlPendingChanges != null : "Must have non-empty pending changes";
 
         // Pretending there are no committed, but not applied yet changes, so that wlCanSendChangesNow() is true.
         // We can do that because the assumption #1 and because any previously committed changes get lost when a
@@ -1114,7 +1114,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
         //   "After an enter event or disable request all state information is invalidated and needs to be resent by the client."
         wlBeingCommittedChanges = null;
 
-        assert(wlCanSendChangesNow());
+        assert wlCanSendChangesNow() : "Must be able to send pending changes now";
         wlSendPendingChangesNow();
 
         // See the assumption #2 above.
@@ -1206,7 +1206,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
 
     /** Called by {@link ClientComponentCaretPositionTracker} */
     boolean wlUpdateCursorRectangle(final boolean forceUpdate) {
-        assert(EventQueue.isDispatchThread());
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         if (log.isLoggable(PlatformLogger.Level.FINER)) {
             log.finer("wlUpdateCursorRectangle(): forceUpdate={0}, this={1}.", forceUpdate, this);
@@ -1290,7 +1290,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
 
     /** Called in response to {@code zwp_text_input_v3::enter} events. */
     private void zwp_text_input_v3_onEnter(long enteredWlSurfacePtr) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         try {
             if (log.isLoggable(PlatformLogger.Level.FINE)) {
@@ -1312,7 +1312,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
 
     /** Called in response to {@code zwp_text_input_v3::leave} events. */
     private void zwp_text_input_v3_onLeave(long leftWlSurfacePtr) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         try {
             if (log.isLoggable(PlatformLogger.Level.FINE)) {
@@ -1335,7 +1335,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
 
     /** Called in response to {@code zwp_text_input_v3::preedit_string} events. */
     private void zwp_text_input_v3_onPreeditString(byte[] preeditStrUtf8, int cursorBeginUtf8Byte, int cursorEndUtf8Byte) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         try {
             if (log.isLoggable(PlatformLogger.Level.FINE)) {
@@ -1355,7 +1355,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
 
     /** Called in response to {@code zwp_text_input_v3::commit_string} events. */
     private void zwp_text_input_v3_onCommitString(byte[] commitStrUtf8) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         try {
             if (log.isLoggable(PlatformLogger.Level.FINE)) {
@@ -1375,7 +1375,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
 
     /** Called in response to {@code zwp_text_input_v3::delete_surrounding_text} events. */
     private void zwp_text_input_v3_onDeleteSurroundingText(long numberOfUtf8BytesBeforeToDelete, long numberOfUtf8BytesAfterToDelete) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         // TODO: support the surrounding text API (set_surrounding_text + set_text_change_cause | delete_surrounding text)
         //       at least for particular cases.
@@ -1394,7 +1394,7 @@ final class WLInputMethodZwpTextInputV3 extends InputMethodAdapter {
 
     /** Called in response to {@code zwp_text_input_v3::done} events. */
     private void zwp_text_input_v3_onDone(long doneSerial) {
-        assert EventQueue.isDispatchThread();
+        assert EventQueue.isDispatchThread() : "Method must only be invoked on EDT";
 
         try {
             if (log.isLoggable(PlatformLogger.Level.FINE)) {

src/java.desktop/unix/native/libawt_wlawt/WLComponentPeer.c

@@ -387,7 +387,7 @@ Java_sun_awt_wl_WLComponentPeer_nativeCreateWindow
 
 static struct xdg_positioner *
 newPositioner
-        (jint width, jint height, jint offsetX, jint offsetY)
+        (jint width, jint height, jint offsetX, jint offsetY, jboolean isUnconstrained)
 {
     struct xdg_positioner *xdg_positioner = xdg_wm_base_create_positioner(xdg_wm_base);
     CHECK_NULL_RETURN(xdg_positioner, NULL);
@@ -400,10 +400,15 @@ newPositioner
     xdg_positioner_set_offset(xdg_positioner, 0, 0);
     xdg_positioner_set_anchor(xdg_positioner, XDG_POSITIONER_ANCHOR_TOP_LEFT);
     xdg_positioner_set_gravity(xdg_positioner, XDG_POSITIONER_GRAVITY_BOTTOM_RIGHT);
-    xdg_positioner_set_constraint_adjustment(xdg_positioner,
-        XDG_POSITIONER_CONSTRAINT_ADJUSTMENT_FLIP_Y
-        | XDG_POSITIONER_CONSTRAINT_ADJUSTMENT_SLIDE_X
-        | XDG_POSITIONER_CONSTRAINT_ADJUSTMENT_SLIDE_Y);
+    if (isUnconstrained) {
+        xdg_positioner_set_constraint_adjustment(xdg_positioner,
+                                                 XDG_POSITIONER_CONSTRAINT_ADJUSTMENT_NONE);
+    } else {
+        xdg_positioner_set_constraint_adjustment(xdg_positioner,
+                                                 XDG_POSITIONER_CONSTRAINT_ADJUSTMENT_FLIP_Y
+                                                 | XDG_POSITIONER_CONSTRAINT_ADJUSTMENT_SLIDE_X
+                                                 | XDG_POSITIONER_CONSTRAINT_ADJUSTMENT_SLIDE_Y);
+    }
     return xdg_positioner;
 }
 
@@ -411,7 +416,8 @@ JNIEXPORT void JNICALL
 Java_sun_awt_wl_WLComponentPeer_nativeCreatePopup
         (JNIEnv *env, jobject obj, jlong ptr, jlong parentPtr, jlong wlSurfacePtr,
          jint width, jint height,
-         jint offsetX, jint offsetY)
+         jint offsetX, jint offsetY,
+         jboolean isUnconstrained)
 {
     struct WLFrame *frame = (struct WLFrame *) ptr;
     struct WLFrame *parentFrame = (struct WLFrame*) parentPtr;
@@ -423,7 +429,7 @@ Java_sun_awt_wl_WLComponentPeer_nativeCreatePopup
     frame->toplevel = JNI_FALSE;
 
     assert(parentFrame);
-    struct xdg_positioner *xdg_positioner = newPositioner(width, height, offsetX, offsetY);
+    struct xdg_positioner *xdg_positioner = newPositioner(width, height, offsetX, offsetY, isUnconstrained);
     CHECK_NULL(xdg_positioner);
     JNU_RUNTIME_ASSERT(env, parentFrame->toplevel, "Popup's parent surface must be a toplevel");
     frame->xdg_popup = xdg_surface_get_popup(frame->xdg_surface, parentFrame->xdg_surface, xdg_positioner);
@@ -436,13 +442,14 @@ JNIEXPORT void JNICALL
 Java_sun_awt_wl_WLComponentPeer_nativeRepositionWLPopup
         (JNIEnv *env, jobject obj, jlong ptr,
          jint width, jint height,
-         jint offsetX, jint offsetY)
+         jint offsetX, jint offsetY,
+         jboolean isUnconstrained)
 {
     struct WLFrame *frame = jlong_to_ptr(ptr);
     assert (!frame->toplevel);
 
     if (wl_proxy_get_version((struct wl_proxy *)xdg_wm_base) >= 3) {
-        struct xdg_positioner *xdg_positioner = newPositioner(width, height, offsetX, offsetY);
+        struct xdg_positioner *xdg_positioner = newPositioner(width, height, offsetX, offsetY, isUnconstrained);
         CHECK_NULL(xdg_positioner);
         static int token = 42; // This will be received by xdg_popup_repositioned(); unused for now.
         xdg_popup_reposition(frame->xdg_popup, xdg_positioner, token++);

test/jdk/jb/javax/swing/wayland/WLPopupUnconstrained.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright 2025 JetBrains s.r.o.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+import javax.swing.JButton;
+import javax.swing.JPanel;
+import javax.swing.JWindow;
+import javax.swing.SwingUtilities;
+import java.awt.GridLayout;
+import java.awt.Window;
+import java.awt.event.MouseEvent;
+import java.awt.event.MouseAdapter;
+import java.util.concurrent.CompletableFuture;
+
+/**
+ * @test
+ * @summary Verifies popups can be located regardless of the screen edge proximity
+ * @requires os.family == "linux"
+ * @key headful
+ * @modules java.desktop/sun.awt
+ * @run main/manual WLPopupUnconstrained
+ */
+public class WLPopupUnconstrained {
+    static final CompletableFuture<RuntimeException> swingError = new CompletableFuture<>();
+
+    public static void main(String[] args) throws Exception {
+        SwingUtilities.invokeAndWait(WLPopupUnconstrained::showUI);
+        swingError.get();
+    }
+
+    private static void showUI() {
+        JFrame frame = new JFrame("Unconstrained popup test");
+        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+
+        JLabel label = new JLabel("Right-click here for a popup.");
+
+        JPanel popupContents = new JPanel();
+        popupContents.add(new JLabel("test popup"));
+        JWindow popup = new JWindow(frame);
+        popup.setType(Window.Type.POPUP);
+        sun.awt.AWTAccessor.getWindowAccessor().setPopupParent(popup, label);
+        popup.getRootPane().putClientProperty("wlawt.popup_position_unconstrained", Boolean.TRUE);
+        popup.setSize(300, 250);
+        popup.add(popupContents);
+        label.addMouseListener(new MouseAdapter() {
+            public void mousePressed(MouseEvent e) {
+                if (e.isPopupTrigger()) {
+                    popup.setLocation(e.getX(), e.getY());
+                    popup.setVisible(true);
+                } else {
+                    popup.setVisible(false);
+                }
+            }
+        });
+        JPanel content = new JPanel();
+        var layout = new GridLayout(3, 2, 10, 10);
+        content.setLayout(layout);
+        content.add(new JLabel("<html><h1>INSTRUCTIONS</h1>" +
+                "<p>Locate this window close to the bottom-right edge of the screen.</p>" +
+                "<p>Make the popup appear (on the right) such that it is partially outside the screen.</p>" +
+                "<p>Press Pass iff the popup indeed crossed the screen edge.</p>" +
+                "<p>Otherwise press Fail.</p></html>"));
+        content.add(label);
+        JButton passButton = new JButton("Pass");
+        passButton.addActionListener(e -> {swingError.complete(null);});
+        JButton failButton = new JButton("Fail");
+        failButton.addActionListener(e -> {swingError.completeExceptionally(new RuntimeException("The tester has pressed FAILED"));});
+        content.add(failButton);
+        content.add(passButton);
+        frame.setContentPane(content);
+        frame.pack();
+        frame.setVisible(true);
+    }
+}