1 files changed, 24 insertions, 0 deletions
diff --git a/container-search/src/main/java/com/yahoo/search/grouping/request/ConstantValueComparator.java b/container-search/src/main/java/com/yahoo/search/grouping/request/ConstantValueComparator.java
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index 00000000000..e8017bbb796
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+++ b/container-search/src/main/java/com/yahoo/search/grouping/request/ConstantValueComparator.java
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.search.grouping.request;
+
+import java.util.Comparator;
+
+/**
+ * This class compares two constant values, and takes into account that one of
+ * the arguments may be the very special infinity value.
+ *
+ * @author <a href="mailto:lulf@yahoo-inc.com">Ulf Lilleengen</a>
+ */
+@SuppressWarnings("rawtypes")
+public class ConstantValueComparator implements Comparator<ConstantValue> {
+    @SuppressWarnings("unchecked")
+    @Override
+    public int compare(ConstantValue lhs, ConstantValue rhs) {
+        // Run infinite comparison method if one of the arguments are infinite.
+        if (rhs instanceof InfiniteValue) {
+            return (-1 * rhs.getValue().compareTo(lhs));
+        }
+        return (lhs.getValue().compareTo(rhs.getValue()));
+    }
+
+}