--- old/src/java.base/share/classes/java/util/ArraysParallelSortHelpers.java	2019-08-27 17:28:49.106324386 -0700
+++ new/src/java.base/share/classes/java/util/ArraysParallelSortHelpers.java	2019-08-27 17:28:48.930324386 -0700
@@ -87,6 +87,7 @@
      * quartile task, that does not need to maintain array state.
      */
     static final class EmptyCompleter extends CountedCompleter<Void> {
+        @java.io.Serial
         static final long serialVersionUID = 2446542900576103244L;
         EmptyCompleter(CountedCompleter<?> p) { super(p); }
         public final void compute() { }
@@ -96,6 +97,7 @@
      * A trigger for secondary merge of two merges
      */
     static final class Relay extends CountedCompleter<Void> {
+        @java.io.Serial
         static final long serialVersionUID = 2446542900576103244L;
         final CountedCompleter<?> task;
         Relay(CountedCompleter<?> task) {
@@ -111,6 +113,7 @@
     /** Object + Comparator support class */
     static final class FJObject {
         static final class Sorter<T> extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final T[] a, w;
             final int base, size, wbase, gran;
@@ -148,6 +151,7 @@
         }
 
         static final class Merger<T> extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final T[] a, w; // main and workspace arrays
             final int lbase, lsize, rbase, rsize, wbase, gran;
@@ -233,6 +237,7 @@
     /** byte support class */
     static final class FJByte {
         static final class Sorter extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final byte[] a, w;
             final int base, size, wbase, gran;
@@ -266,6 +271,7 @@
         }
 
         static final class Merger extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final byte[] a, w; // main and workspace arrays
             final int lbase, lsize, rbase, rsize, wbase, gran;
@@ -344,6 +350,7 @@
     /** char support class */
     static final class FJChar {
         static final class Sorter extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final char[] a, w;
             final int base, size, wbase, gran;
@@ -377,6 +384,7 @@
         }
 
         static final class Merger extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final char[] a, w; // main and workspace arrays
             final int lbase, lsize, rbase, rsize, wbase, gran;
@@ -455,6 +463,7 @@
     /** short support class */
     static final class FJShort {
         static final class Sorter extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final short[] a, w;
             final int base, size, wbase, gran;
@@ -488,6 +497,7 @@
         }
 
         static final class Merger extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final short[] a, w; // main and workspace arrays
             final int lbase, lsize, rbase, rsize, wbase, gran;
@@ -566,6 +576,7 @@
     /** int support class */
     static final class FJInt {
         static final class Sorter extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final int[] a, w;
             final int base, size, wbase, gran;
@@ -599,6 +610,7 @@
         }
 
         static final class Merger extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final int[] a, w; // main and workspace arrays
             final int lbase, lsize, rbase, rsize, wbase, gran;
@@ -677,6 +689,7 @@
     /** long support class */
     static final class FJLong {
         static final class Sorter extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final long[] a, w;
             final int base, size, wbase, gran;
@@ -710,6 +723,7 @@
         }
 
         static final class Merger extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final long[] a, w; // main and workspace arrays
             final int lbase, lsize, rbase, rsize, wbase, gran;
@@ -788,6 +802,7 @@
     /** float support class */
     static final class FJFloat {
         static final class Sorter extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final float[] a, w;
             final int base, size, wbase, gran;
@@ -821,6 +836,7 @@
         }
 
         static final class Merger extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final float[] a, w; // main and workspace arrays
             final int lbase, lsize, rbase, rsize, wbase, gran;
@@ -899,6 +915,7 @@
     /** double support class */
     static final class FJDouble {
         static final class Sorter extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final double[] a, w;
             final int base, size, wbase, gran;
@@ -932,6 +949,7 @@
         }
 
         static final class Merger extends CountedCompleter<Void> {
+            @java.io.Serial
             static final long serialVersionUID = 2446542900576103244L;
             final double[] a, w; // main and workspace arrays
             final int lbase, lsize, rbase, rsize, wbase, gran;