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diff --git a/vespajlib/src/main/java/com/yahoo/collections/PredicateSplit.java b/vespajlib/src/main/java/com/yahoo/collections/PredicateSplit.java
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+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.collections;
+
+import java.util.List;
+import java.util.ArrayList;
+import java.util.function.Predicate;
+
+/**
+ * Class holding the result of a partition-by-predicate operation.
+ **/
+public class PredicateSplit<E> {
+    public final List<E> falseValues; /// list of values where the predicate returned false
+    public final List<E> trueValues;  /// list of values where the predicate returned true
+
+    private PredicateSplit() {
+	falseValues = new ArrayList<E>();
+	trueValues = new ArrayList<E>();
+    }
+
+    /**
+     * Perform a partition-by-predicate operation.
+     * Each value in the input is tested by the predicate and
+     * added to either the falseValues list or the trueValues list.
+     * @param collection The input collection.
+     * @param predicate A test for selecting the target list.
+     * @return Two lists bundled in an object.
+     **/
+    public static <V> PredicateSplit<V> partition(Iterable<V> collection, Predicate<? super V> predicate)
+    {
+        PredicateSplit<V> r = new PredicateSplit<V>();
+        for (V value : collection) {
+            if (predicate.test(value)) {
+                r.trueValues.add(value);
+            } else {
+                r.falseValues.add(value);
+            }
+        }
+        return r;
+    }
+}