8365077: java.awt.font.NumericShaper violates equals/hashCode contract

Reviewed-by: kizune, psadhukhan

src/java.desktop/share/classes/java/awt/font/NumericShaper.java

@@ -346,6 +346,19 @@ public final class NumericShaper implements java.io.Serializable {
             return index < NUM_KEYS ? Range.values()[index] : null;
         }
 
+        private static int toRangeHash(Set<Range> ranges) {
+            int m = 0;
+            for (Range range : ranges) {
+                int index = range.ordinal();
+                if (index < NUM_KEYS) {
+                    m |= 1 << index;
+                } else {
+                    m |=  (1 << NUM_KEYS) + index;
+                }
+            }
+            return m;
+        }
+
         private static int toRangeMask(Set<Range> ranges) {
             int m = 0;
             for (Range range : ranges) {
@@ -576,7 +589,7 @@ public final class NumericShaper implements java.io.Serializable {
     // and a linear probe is ok.
 
     private static int ctCache = 0;
-    private static int ctCacheLimit = contexts.length - 2;
+    private static final int ctCacheLimit = contexts.length - 2;
 
     // warning, synchronize access to this as it modifies state
     private static int getContextKey(char c) {
@@ -1510,6 +1523,9 @@ public final class NumericShaper implements java.io.Serializable {
     private NumericShaper(int key, int mask) {
         this.key = key;
         this.mask = mask;
+        if (((this.mask & ARABIC) != 0) && ((this.mask & EASTERN_ARABIC) != 0)) {
+            this.mask &= ~ARABIC;
+        }
     }
 
     private NumericShaper(Range defaultContext, Set<Range> ranges) {
@@ -1795,15 +1811,7 @@ public final class NumericShaper implements java.io.Serializable {
      * @see java.lang.Object#hashCode
      */
     public int hashCode() {
-        int hash = mask;
-        if (rangeSet != null) {
-            // Use the CONTEXTUAL_MASK bit only for the enum-based
-            // NumericShaper. A deserialized NumericShaper might have
-            // bit masks.
-            hash &= CONTEXTUAL_MASK;
-            hash ^= rangeSet.hashCode();
-        }
-        return hash;
+        return (rangeSet != null) ? Range.toRangeHash(rangeSet) : (mask & ~CONTEXTUAL_MASK);
     }
 
     /**

test/jdk/java/awt/font/NumericShaper/NSEqualsTest.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+ * 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.
+ */
+
+/*
+ * @test
+ * @bug 8365077
+ * @summary confirm that an instance which is created with Enum ranges is
+ * equal to another instance which is created with equivalent traditional
+ * ranges, and that in such a case the hashCodes are also equal.
+ */
+
+import java.awt.font.NumericShaper;
+import java.awt.font.NumericShaper.Range;
+import static java.awt.font.NumericShaper.Range.*;
+import java.util.EnumSet;
+
+public class NSEqualsTest {
+
+    public static void main(String[] args) {
+
+        for (Range r1 : Range.values()) {
+           test(r1);
+           for (Range r2 : Range.values()) {
+              test(r1, r2);
+           }
+        }
+    }
+
+    static void test(Range r) {
+        if (r.ordinal() > MONGOLIAN.ordinal()) {
+            return;
+        }
+        int o = 1 << r.ordinal();
+        NumericShaper nsr = NumericShaper.getContextualShaper(EnumSet.of(r));
+        NumericShaper nso = NumericShaper.getContextualShaper(o);
+        printAndCompare(nsr, nso);
+    }
+
+    static void test(Range r1, Range r2) {
+        if (r1.ordinal() > MONGOLIAN.ordinal() || r2.ordinal() > MONGOLIAN.ordinal()) {
+            return;
+        }
+        int o1 = 1 << r1.ordinal();
+        int o2 = 1 << r2.ordinal();
+
+        NumericShaper nsr = NumericShaper.getContextualShaper(EnumSet.of(r1, r2));
+        NumericShaper nso = NumericShaper.getContextualShaper(o1 | o2);
+        printAndCompare(nsr, nso);
+    }
+
+    static void printAndCompare(NumericShaper nsr, NumericShaper nso) {
+        System.err.println(nsr);
+        System.err.println(nso);
+        System.err.println(nsr.hashCode() + " vs " + nso.hashCode() +
+                           " equal: " + nsr.equals(nso));
+        if (!nsr.equals(nso)) {
+            throw new RuntimeException("Expected equal");
+        }
+        if (nsr.hashCode() != nso.hashCode()) {
+            throw new RuntimeException("Different hash codes:");
+        }
+    }
+}
+