--- old/src/java.desktop/macosx/native/libawt_lwawt/awt/AWTEvent.m	2019-03-11 19:59:36.000000000 +0300
+++ new/src/java.desktop/macosx/native/libawt_lwawt/awt/AWTEvent.m	2019-03-11 19:59:36.000000000 +0300
@@ -243,16 +243,20 @@
     //NSUInteger cgsRightMask;
     unsigned short leftKeyCode;
     unsigned short rightKeyCode;
+    BOOL leftKeyPressed;
+    BOOL rightKeyPressed;
     jint javaExtMask;
     jint javaMask;
     jint javaKey;
 }
-const nsKeyToJavaModifierTable[] =
+nsKeyToJavaModifierTable[] =
 {
     {
         NSAlphaShiftKeyMask,
         0,
         0,
+        NO,
+        NO,
         0, // no Java equivalent
         0, // no Java equivalent
         java_awt_event_KeyEvent_VK_CAPS_LOCK
@@ -263,6 +267,8 @@
         //kCGSFlagsMaskAppleRightShiftKey,
         56,
         60,
+        NO,
+        NO,
         java_awt_event_InputEvent_SHIFT_DOWN_MASK,
         java_awt_event_InputEvent_SHIFT_MASK,
         java_awt_event_KeyEvent_VK_SHIFT
@@ -273,6 +279,8 @@
         //kCGSFlagsMaskAppleRightControlKey,
         59,
         62,
+        NO,
+        NO,
         java_awt_event_InputEvent_CTRL_DOWN_MASK,
         java_awt_event_InputEvent_CTRL_MASK,
         java_awt_event_KeyEvent_VK_CONTROL
@@ -283,6 +291,8 @@
         //kCGSFlagsMaskAppleRightCommandKey,
         55,
         54,
+        NO,
+        NO,
         java_awt_event_InputEvent_META_DOWN_MASK,
         java_awt_event_InputEvent_META_MASK,
         java_awt_event_KeyEvent_VK_META
@@ -292,35 +302,28 @@
         //kCGSFlagsMaskAppleLeftAlternateKey,
         //kCGSFlagsMaskAppleRightAlternateKey,
         58,
-        0,
+        61,
+        NO,
+        NO,
         java_awt_event_InputEvent_ALT_DOWN_MASK,
         java_awt_event_InputEvent_ALT_MASK,
         java_awt_event_KeyEvent_VK_ALT
     },
-    {
-        NSAlternateKeyMask,
-        0,
-        61,
-        java_awt_event_InputEvent_ALT_DOWN_MASK | java_awt_event_InputEvent_ALT_GRAPH_DOWN_MASK,
-        java_awt_event_InputEvent_ALT_MASK | java_awt_event_InputEvent_ALT_GRAPH_MASK,
-        java_awt_event_KeyEvent_VK_ALT | java_awt_event_KeyEvent_VK_ALT_GRAPH
-    },
     // NSNumericPadKeyMask
     {
         NSHelpKeyMask,
         0,
         0,
+        NO,
+        NO,
         0, // no Java equivalent
         0, // no Java equivalent
         java_awt_event_KeyEvent_VK_HELP
     },
     // NSFunctionKeyMask
-    {0, 0, 0, 0, 0, 0}
+    {0, 0, 0, NO, NO, 0, 0, 0}
 };
 
-static BOOL leftAltKeyPressed;
-static BOOL altGRPressed = NO;
-
 /*
  * Almost all unicode characters just go from NS to Java with no translation.
  *  For the few exceptions, we handle it here with this small table.
@@ -521,7 +524,7 @@
 {
     static NSUInteger sPreviousNSFlags = 0;
 
-    const struct _nsKeyToJavaModifier* cur;
+    struct _nsKeyToJavaModifier* cur;
     NSUInteger oldNSFlags = sPreviousNSFlags;
     NSUInteger changedNSFlags = oldNSFlags ^ nsFlags;
     sPreviousNSFlags = nsFlags;
@@ -531,27 +534,37 @@
     *javaKeyType = java_awt_event_KeyEvent_KEY_PRESSED;
 
     for (cur = nsKeyToJavaModifierTable; cur->nsMask != 0; ++cur) {
-        if (changedNSFlags & cur->nsMask) {
-            *javaKeyCode = cur->javaKey;
-            *javaKeyLocation = java_awt_event_KeyEvent_KEY_LOCATION_STANDARD;
-            // TODO: uses SPI...
-            //if (changedNSFlags & cur->cgsLeftMask) {
-            //    *javaKeyLocation = java_awt_event_KeyEvent_KEY_LOCATION_LEFT;
-            //} else if (changedNSFlags & cur->cgsRightMask) {
-            //    *javaKeyLocation = java_awt_event_KeyEvent_KEY_LOCATION_RIGHT;
-            //}
-            if (eventKeyCode == cur->leftKeyCode) {
-                leftAltKeyPressed = YES;
+        if (eventKeyCode != 0) {
+            // if key code is specified we are able to determine its location
+            // also it is possible to track the pressed state of the corresponding key
+            if (cur->leftKeyCode == eventKeyCode) {
+                // specified key code switches the pressed state only if the current mask is set
+                cur->leftKeyPressed = !cur->leftKeyPressed && (cur->nsMask & nsFlags);
+                *javaKeyCode = cur->javaKey;
                 *javaKeyLocation = java_awt_event_KeyEvent_KEY_LOCATION_LEFT;
-            } else if (eventKeyCode == cur->rightKeyCode) {
+                *javaKeyType = cur->leftKeyPressed
+                        ? java_awt_event_KeyEvent_KEY_PRESSED
+                        : java_awt_event_KeyEvent_KEY_RELEASED;
+                break;
+            }
+            if (cur->rightKeyCode == eventKeyCode) {
+                // specified key code switches the pressed state only if the current mask is set
+                cur->rightKeyPressed = !cur->rightKeyPressed && (cur->nsMask & nsFlags);
+                *javaKeyCode = cur->javaKey;
                 *javaKeyLocation = java_awt_event_KeyEvent_KEY_LOCATION_RIGHT;
-            } else if (cur->nsMask == NSAlternateKeyMask) {
-                leftAltKeyPressed = NO;
-                continue;
+                *javaKeyType = cur->rightKeyPressed
+                        ? java_awt_event_KeyEvent_KEY_PRESSED
+                        : java_awt_event_KeyEvent_KEY_RELEASED;
+                break;
             }
-            *javaKeyType = (cur->nsMask & nsFlags) ?
-            java_awt_event_KeyEvent_KEY_PRESSED :
-            java_awt_event_KeyEvent_KEY_RELEASED;
+        }
+        // skip current record in the table if current mask is not changed
+        if (changedNSFlags & cur->nsMask) {
+            *javaKeyCode = cur->javaKey;
+            *javaKeyLocation = java_awt_event_KeyEvent_KEY_LOCATION_STANDARD;
+            *javaKeyType = (cur->nsMask & nsFlags)
+                    ? java_awt_event_KeyEvent_KEY_PRESSED
+                    : java_awt_event_KeyEvent_KEY_RELEASED;
             break;
         }
     }
@@ -563,22 +576,10 @@
 jint NsKeyModifiersToJavaModifiers(NSUInteger nsFlags, BOOL isExtMods)
 {
     jint javaModifiers = 0;
-    const struct _nsKeyToJavaModifier* cur;
+    struct _nsKeyToJavaModifier* cur;
 
     for (cur = nsKeyToJavaModifierTable; cur->nsMask != 0; ++cur) {
-        if ((cur->nsMask & nsFlags) != 0) {
-
-            if (cur->nsMask == NSAlternateKeyMask) {
-                if (leftAltKeyPressed == YES) {
-                    javaModifiers |= isExtMods? cur->javaExtMask : cur->javaMask;
-                    if (altGRPressed == NO)
-                        break;
-                    } else {
-                        leftAltKeyPressed = YES;
-                        altGRPressed = YES;
-                        continue;
-                    }
-                }
+        if (cur->nsMask & nsFlags) {
             javaModifiers |= isExtMods ? cur->javaExtMask : cur->javaMask;
         }
     }
@@ -592,7 +593,7 @@
 NSUInteger JavaModifiersToNsKeyModifiers(jint javaModifiers, BOOL isExtMods)
 {
     NSUInteger nsFlags = 0;
-    const struct _nsKeyToJavaModifier* cur;
+    struct _nsKeyToJavaModifier* cur;
 
     for (cur = nsKeyToJavaModifierTable; cur->nsMask != 0; ++cur) {
         jint mask = isExtMods? cur->javaExtMask : cur->javaMask;
@@ -600,15 +601,6 @@
             nsFlags |= cur->nsMask;
         }
     }
-
-    // special case
-    jint mask = isExtMods? java_awt_event_InputEvent_ALT_GRAPH_DOWN_MASK :
-                           java_awt_event_InputEvent_ALT_GRAPH_MASK;
-
-    if ((mask & javaModifiers) != 0) {
-        nsFlags |= NSAlternateKeyMask;
-    }
-
     return nsFlags;
 }