diff --git a/src/java.desktop/share/classes/java/awt/font/NumericShaper.java b/src/java.desktop/share/classes/java/awt/font/NumericShaper.java
index 99b59cc2e0ec3..44b7b1a23fec6 100644
--- a/src/java.desktop/share/classes/java/awt/font/NumericShaper.java
+++ b/src/java.desktop/share/classes/java/awt/font/NumericShaper.java
@@ -1441,6 +1441,9 @@ public static NumericShaper getShaper(Range singleRange) {
      * EUROPEAN digits are encountered before any strong directional
      * text in the string, the context is presumed to be EUROPEAN, and
      * so the digits will not shape.
+     * Any bit set in the {@code ranges} bitmask which is not a
+     * recognised value is discarded. Similarly if two bits are
+     * specified where one takes precedence, the lesser one is discarded.
      * @param ranges the specified Unicode ranges
      * @return a shaper for the specified ranges
      */
@@ -1460,6 +1463,9 @@ public static NumericShaper getContextualShaper(int ranges) {
      * directional text in the string, the context is presumed to be
      * EUROPEAN, and so the digits will not shape.
      *
+     * If two ranges are specified where one takes precedence over the
+     * other the lesser range is discarded.
+     *
      * @param ranges the specified Unicode ranges
      * @return a contextual shaper for the specified ranges
      * @throws NullPointerException if {@code ranges} is {@code null}.
@@ -1499,6 +1505,9 @@ public static NumericShaper getContextualShaper(int ranges, int defaultContext)
      * range is one of the provided ranges. The shaper uses {@code
      * defaultContext} as the starting context.
      *
+     * If two ranges are specified where one takes precedence over the
+     * other the lesser range is discarded.
+     *
      * @param ranges the specified Unicode ranges
      * @param defaultContext the starting context, such as
      *                       {@code NumericShaper.Range.EUROPEAN}
@@ -1522,7 +1531,7 @@ public static NumericShaper getContextualShaper(Set<Range> ranges,
      */
     private NumericShaper(int key, int mask) {
         this.key = key;
-        this.mask = mask;
+        this.mask = mask & (CONTEXTUAL_MASK | ALL_RANGES);
         if (((this.mask & ARABIC) != 0) && ((this.mask & EASTERN_ARABIC) != 0)) {
             this.mask &= ~ARABIC;
         }
diff --git a/test/jdk/java/awt/font/NumericShaper/NSEqualsTest.java b/test/jdk/java/awt/font/NumericShaper/NSEqualsTest.java
index 6af73b7efa2ff..cc1c078bf7937 100644
--- a/test/jdk/java/awt/font/NumericShaper/NSEqualsTest.java
+++ b/test/jdk/java/awt/font/NumericShaper/NSEqualsTest.java
@@ -23,7 +23,7 @@
 
 /*
  * @test
- * @bug 8365077
+ * @bug 8365077 8370160
  * @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.
@@ -38,6 +38,12 @@ public class NSEqualsTest {
 
     public static void main(String[] args) {
 
+        // Invalid ranges should be discarded
+        NumericShaper cs1 =
+            NumericShaper.getContextualShaper(NumericShaper.ALL_RANGES);
+        NumericShaper cs2 = NumericShaper.getContextualShaper(-1);
+        printAndCompare(cs1, cs2);
+
         for (Range r1 : Range.values()) {
            test(r1);
            for (Range r2 : Range.values()) {