8259680: Need API to query states of CAPS LOCK and NUM LOCK keys

Reviewed-by: arapte, pbansal

Author: kevinrushforth

modules/javafx.graphics/src/main/java/com/sun/glass/events/KeyEvent.java

@@ -68,6 +68,13 @@ public class KeyEvent {
     @Native public final static int MODIFIER_BUTTON_BACK       = 1 << 8;
     @Native public final static int MODIFIER_BUTTON_FORWARD    = 1 << 9;
 
+    /*
+     * Key lock state
+     */
+    @Native public static final int KEY_LOCK_OFF = 0;
+    @Native public static final int KEY_LOCK_ON = 1;
+    @Native public static final int KEY_LOCK_UNKNOWN = -1;
+
     /*
      * Key event key codes.
      */

modules/javafx.graphics/src/main/java/com/sun/glass/ui/Application.java

@@ -36,6 +36,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.LinkedList;
+import java.util.Optional;
 
 public abstract class Application {
 
@@ -744,4 +745,22 @@ public final boolean supportsSystemMenu() {
     public static int getKeyCodeForChar(char c) {
         return application._getKeyCodeForChar(c);
     }
+
+    protected int _isKeyLocked(int keyCode) {
+        // Overridden in subclasses
+        return KeyEvent.KEY_LOCK_UNKNOWN;
+    }
+
+    public final Optional<Boolean> isKeyLocked(int keyCode) {
+        checkEventThread();
+        int lockState = _isKeyLocked(keyCode);
+        switch (lockState) {
+            case KeyEvent.KEY_LOCK_OFF:
+                return Optional.of(false);
+            case KeyEvent.KEY_LOCK_ON:
+                return Optional.of(true);
+            default:
+                return Optional.empty();
+        }
+    }
 }

modules/javafx.graphics/src/main/java/com/sun/glass/ui/gtk/GtkApplication.java

@@ -478,4 +478,7 @@ protected boolean _supportsInputMethods() {
     @Override
     protected native int _getKeyCodeForChar(char c);
 
+    @Override
+    protected native int _isKeyLocked(int keyCode);
+
 }

modules/javafx.graphics/src/main/java/com/sun/glass/ui/mac/MacApplication.java

@@ -391,4 +391,7 @@ public String getDataDirectory() {
 
     @Override
     protected native int _getKeyCodeForChar(char c);
+
+    @Override
+    protected native int _isKeyLocked(int keyCode);
 }

modules/javafx.graphics/src/main/java/com/sun/glass/ui/win/WinApplication.java

@@ -358,4 +358,7 @@ public String getDataDirectory() {
 
     @Override
     protected native int _getKeyCodeForChar(char c);
+
+    @Override
+    protected native int _isKeyLocked(int keyCode);
 }

modules/javafx.graphics/src/main/java/com/sun/javafx/tk/DummyToolkit.java

@@ -67,6 +67,7 @@
 import com.sun.scenario.animation.AbstractPrimaryTimer;
 import com.sun.scenario.effect.FilterContext;
 import com.sun.scenario.effect.Filterable;
+import java.util.Optional;
 
 /**
  * A stubbed out Toolkit that provides no useful implementation. This is used
@@ -371,6 +372,11 @@ public KeyCode getPlatformShortcutKey() {
         throw new UnsupportedOperationException("Not supported yet.");
     }
 
+    @Override
+    public Optional<Boolean> isKeyLocked(KeyCode keyCode) {
+        throw new UnsupportedOperationException("Not supported yet.");
+    }
+
     @Override
     public FileChooserResult showFileChooser(TKStage ownerWindow,
                                       String title,

modules/javafx.graphics/src/main/java/com/sun/javafx/tk/Toolkit.java

@@ -94,6 +94,7 @@
 import com.sun.scenario.effect.Color4f;
 import com.sun.scenario.effect.FilterContext;
 import com.sun.scenario.effect.Filterable;
+import java.util.Optional;
 
 
 public abstract class Toolkit {
@@ -873,6 +874,13 @@ public KeyCode getPlatformShortcutKey() {
         return PlatformUtil.isMac() ? KeyCode.META : KeyCode.CONTROL;
     }
 
+    /**
+     * Returns the lock state for the given keyCode.
+     * @param keyCode the keyCode to check
+     * @return the lock state for the given keyCode.
+     */
+    public abstract Optional<Boolean> isKeyLocked(KeyCode keyCode);
+
     public abstract FileChooserResult showFileChooser(
             TKStage ownerWindow,
             String title,

modules/javafx.graphics/src/main/java/com/sun/javafx/tk/quantum/QuantumToolkit.java

@@ -133,6 +133,7 @@
 import com.sun.javafx.logging.PulseLogger;
 import static com.sun.javafx.logging.PulseLogger.PULSE_LOGGING_ENABLED;
 import com.sun.javafx.scene.input.DragboardHelper;
+import java.util.Optional;
 
 public final class QuantumToolkit extends Toolkit {
 
@@ -1236,6 +1237,24 @@ public boolean isMSAASupported() {
         return  GraphicsPipeline.getPipeline().isMSAASupported();
     }
 
+    // Returns the glass keycode for the given JavaFX KeyCode.
+    // This method only converts lock state KeyCode values
+    private int toGlassKeyCode(KeyCode keyCode) {
+        switch (keyCode) {
+            case CAPS:
+                return com.sun.glass.events.KeyEvent.VK_CAPS_LOCK;
+            case NUM_LOCK:
+                return com.sun.glass.events.KeyEvent.VK_NUM_LOCK;
+            default:
+                return com.sun.glass.events.KeyEvent.VK_UNDEFINED;
+        }
+    }
+
+    @Override
+    public Optional<Boolean> isKeyLocked(KeyCode keyCode) {
+        return Application.GetApplication().isKeyLocked(toGlassKeyCode(keyCode));
+    }
+
     static TransferMode clipboardActionToTransferMode(final int action) {
         switch (action) {
             case Clipboard.ACTION_NONE:

modules/javafx.graphics/src/main/java/javafx/application/Platform.java

@@ -25,10 +25,12 @@
 
 package javafx.application;
 
+import com.sun.javafx.application.PlatformImpl;
 import com.sun.javafx.tk.Toolkit;
+import java.util.Optional;
 import javafx.beans.property.ReadOnlyBooleanProperty;
 import javafx.beans.property.ReadOnlyBooleanWrapper;
-import com.sun.javafx.application.PlatformImpl;
+import javafx.scene.input.KeyCode;
 
 /**
  * Application platform support class.
@@ -329,6 +331,43 @@ public static void exitNestedEventLoop(Object key, Object rval) {
         Toolkit.getToolkit().exitNestedEventLoop(key, rval);
     }
 
+    /**
+     * Returns a flag indicating whether the key corresponding to {@code keyCode}
+     * is in the locked (or "on") state.
+     * {@code keyCode} must be one of: {@link KeyCode#CAPS} or
+     * {@link KeyCode#NUM_LOCK}.
+     * If the underlying system is not able to determine the state of the
+     * specified {@code keyCode}, an empty {@code Optional} is returned.
+     * If the keyboard attached to the system doesn't have the specified key,
+     * an {@code Optional} containing {@code false} is returned.
+     * This method must be called on the JavaFX Application thread.
+     *
+     * @param keyCode the {@code KeyCode} of the lock state to query
+     *
+     * @return the lock state of the key corresponding to {@code keyCode},
+     * or an empty {@code Optional} if the system cannot determine its state
+     *
+     * @throws IllegalArgumentException if {@code keyCode} is not one of the
+     * valid {@code KeyCode} values
+     *
+     * @throws IllegalStateException if this method is called on a thread
+     * other than the JavaFX Application Thread
+     *
+     * @since 17
+     */
+    public static Optional<Boolean> isKeyLocked(KeyCode keyCode) {
+        Toolkit.getToolkit().checkFxUserThread();
+
+        switch (keyCode) {
+            case CAPS:
+            case NUM_LOCK:
+                break;
+            default:
+                throw new IllegalArgumentException("Invalid KeyCode");
+        }
+        return Toolkit.getToolkit().isKeyLocked(keyCode);
+    }
+
     /**
      * Checks whether a nested event loop is running, returning true to indicate
      * that one is, and false if there are no nested event loops currently

modules/javafx.graphics/src/main/native-glass/gtk/glass_key.cpp

@@ -29,6 +29,7 @@
 #include <glib.h>
 #include "glass_general.h"
 #include <gdk/gdkkeysyms.h>
+#include <X11/XKBlib.h>
 
 static gboolean key_initialized = FALSE;
 static GHashTable *keymap;
@@ -345,4 +346,63 @@ JNIEXPORT jint JNICALL Java_com_sun_glass_ui_gtk_GtkApplication__1getKeyCodeForC
     return gdk_keyval_to_glass(keyval);
 }
 
+/*
+ * Function to determine whether the Xkb extention is available. This is a
+ * precaution against X protocol errors, although it should be available on all
+ * Linux systems.
+ */
+
+static Bool xkbInitialized = False;
+static Bool xkbAvailable = False;
+
+static Bool isXkbAvailable(Display *display) {
+    if (!xkbInitialized) {
+        int xkbMajor = XkbMajorVersion;
+        int xkbMinor = XkbMinorVersion;
+        xkbAvailable = XkbQueryExtension(display, NULL, NULL, NULL, &xkbMajor, &xkbMinor);
+        xkbInitialized = True;
+    }
+    return xkbAvailable;
+}
+
+/*
+ * Class:     com_sun_glass_ui_gtk_GtkApplication
+ * Method:    _isKeyLocked
+ * Signature: (I)I
+ */
+JNIEXPORT jint JNICALL Java_com_sun_glass_ui_gtk_GtkApplication__1isKeyLocked
+  (JNIEnv * env, jobject obj, jint keyCode)
+{
+    Display* display = gdk_x11_display_get_xdisplay(gdk_display_get_default());
+    if (!isXkbAvailable(display)) {
+        return com_sun_glass_events_KeyEvent_KEY_LOCK_UNKNOWN;
+    }
+
+    Atom keyCodeAtom = None;
+    switch (keyCode) {
+        case com_sun_glass_events_KeyEvent_VK_CAPS_LOCK:
+            keyCodeAtom = XInternAtom(display, "Caps Lock", True);
+            break;
+
+        case com_sun_glass_events_KeyEvent_VK_NUM_LOCK:
+            keyCodeAtom = XInternAtom(display, "Num Lock", True);
+            break;
+    }
+
+    if (keyCodeAtom == None) {
+        return com_sun_glass_events_KeyEvent_KEY_LOCK_UNKNOWN;
+    }
+
+    Bool isLocked = False;
+    if (XkbGetNamedIndicator(display, keyCodeAtom, NULL, &isLocked, NULL, NULL)) {
+        if (isLocked) {
+            return com_sun_glass_events_KeyEvent_KEY_LOCK_ON;
+        } else {
+            return com_sun_glass_events_KeyEvent_KEY_LOCK_OFF;
+        }
+    }
+
+    return com_sun_glass_events_KeyEvent_KEY_LOCK_UNKNOWN;
+}
+
 } // extern "C"

modules/javafx.graphics/src/main/native-glass/mac/GlassKey.m

@@ -396,3 +396,25 @@ BOOL GetMacKey(jint javaKeyCode, unsigned short *outMacKeyCode)
     return [GlassApplication getKeyCodeForChar:c];
 }
 
+/*
+ * Class:     com_sun_glass_ui_mac_MacApplication
+ * Method:    _isKeyLocked
+ * Signature: (I)I
+ */
+JNIEXPORT jint JNICALL Java_com_sun_glass_ui_mac_MacApplication__1isKeyLocked
+  (JNIEnv * env, jobject obj, jint keyCode)
+{
+    NSUInteger mask = 0;
+    switch (keyCode) {
+        case com_sun_glass_events_KeyEvent_VK_CAPS_LOCK:
+            mask = NSEventModifierFlagCapsLock;
+            break;
+
+        // Caps lock is the only locking key supported on macOS
+        default:
+            return com_sun_glass_events_KeyEvent_KEY_LOCK_UNKNOWN;
+    }
+    NSUInteger modifierFlags = [NSEvent modifierFlags];
+    return (modifierFlags & mask) ? com_sun_glass_events_KeyEvent_KEY_LOCK_ON
+                                  : com_sun_glass_events_KeyEvent_KEY_LOCK_OFF;
+}

modules/javafx.graphics/src/main/native-glass/win/KeyTable.cpp

@@ -247,5 +247,27 @@ JNIEXPORT jint JNICALL Java_com_sun_glass_ui_win_WinApplication__1getKeyCodeForC
     return WindowsKeyToJavaKey(vkey);
 }
 
+/*
+ * Class:     com_sun_glass_ui_win_WinApplication
+ * Method:    _isKeyLocked
+ * Signature: (I)I
+ */
+JNIEXPORT jint JNICALL Java_com_sun_glass_ui_win_WinApplication__1isKeyLocked
+  (JNIEnv * env, jobject obj, jint keyCode)
+{
+    SHORT keyState = 0;
+    switch (keyCode) {
+        case com_sun_glass_events_KeyEvent_VK_CAPS_LOCK:
+            keyState = ::GetKeyState(VK_CAPITAL);
+            break;
 
+        case com_sun_glass_events_KeyEvent_VK_NUM_LOCK:
+            keyState = ::GetKeyState(VK_NUMLOCK);
+            break;
 
+        default:
+            return com_sun_glass_events_KeyEvent_KEY_LOCK_UNKNOWN;
+    }
+    return (keyState & 0x1) ? com_sun_glass_events_KeyEvent_KEY_LOCK_ON
+                            : com_sun_glass_events_KeyEvent_KEY_LOCK_OFF;
+}

modules/javafx.graphics/src/test/java/test/com/sun/javafx/pgstub/StubToolkit.java

@@ -750,6 +750,11 @@ public KeyCode getPlatformShortcutKey() {
         return platformShortcutKey;
     }
 
+    @Override
+    public Optional<Boolean> isKeyLocked(KeyCode keyCode) {
+        return Optional.empty();
+    }
+
     private DndDelegate dndDelegate;
     public void setDndDelegate(DndDelegate dndDelegate) {
         this.dndDelegate = dndDelegate;