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diff --git a/vespajlib/src/main/java/com/yahoo/collections/IntArrayComparator.java b/vespajlib/src/main/java/com/yahoo/collections/IntArrayComparator.java
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+++ b/vespajlib/src/main/java/com/yahoo/collections/IntArrayComparator.java
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+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.collections;
+
+/**
+ * Utility class which is useful when implementing <code>Comparable</code> and one needs to
+ * compare int arrays as instance variables.
+ *
+ * @author <a href="mailto:einarmr@yahoo-inc.com">Einar M R Rosenvinge</a>
+ */
+public class IntArrayComparator {
+    /**
+     * Compare the arguments. Shorter arrays are always considered
+     * smaller than longer arrays. For arrays of equal lengths, the elements
+     * are compared one-by-one. Whenever two corresponding elements in the
+     * two arrays are non-equal, the method returns. If all elements at
+     * corresponding positions in the two arrays are equal, the arrays
+     * are considered equal.
+     *
+     * @param first an int array to be compared
+     * @param second an int array to be compared
+     * @return 0 if the arguments are equal, -1 if the first argument is smaller, 1 if the second argument is smaller
+     * @throws NullPointerException if any of the arguments are null
+     */
+    public static int compare(int[] first, int[] second) {
+        if (first.length < second.length) {
+            return -1;
+        }
+        if (first.length > second.length) {
+            return 1;
+        }
+
+        //lengths are equal, compare contents
+        for (int i = 0; i < first.length; i++) {
+            if (first[i] < second[i]) {
+                return -1;
+            } else if (first[i] > second[i]) {
+                return 1;
+            }
+            //values at index i are equal, continue...
+        }
+
+        //we haven't returned yet; contents must be equal:
+        return 0;
+    }
+}