--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/eclipse/jetty/util/statistic/CounterStatistic.java	Wed Sep 07 21:15:48 2016 -0600
@@ -0,0 +1,117 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
+//  ------------------------------------------------------------------------
+//  All rights reserved. This program and the accompanying materials
+//  are made available under the terms of the Eclipse Public License v1.0
+//  and Apache License v2.0 which accompanies this distribution.
+//
+//      The Eclipse Public License is available at
+//      http://www.eclipse.org/legal/epl-v10.html
+//
+//      The Apache License v2.0 is available at
+//      http://www.opensource.org/licenses/apache2.0.php
+//
+//  You may elect to redistribute this code under either of these licenses.
+//  ========================================================================
+//
+
+package org.eclipse.jetty.util.statistic;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+import org.eclipse.jetty.util.Atomics;
+
+
+/* ------------------------------------------------------------ */
+/** Statistics on a counter value.
+ * <p>
+ * Keep total, current and maximum values of a counter that
+ * can be incremented and decremented. The total refers only
+ * to increments.
+ *
+ */
+public class CounterStatistic
+{
+    protected final AtomicLong _max = new AtomicLong();
+    protected final AtomicLong _curr = new AtomicLong();
+    protected final AtomicLong _total = new AtomicLong();
+
+    /* ------------------------------------------------------------ */
+    public void reset()
+    {
+        reset(0);
+    }
+
+    /* ------------------------------------------------------------ */
+    public void reset(final long value)
+    {
+        _max.set(value);
+        _curr.set(value);
+        _total.set(0); // total always set to 0 to properly calculate cumulative total
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @param delta the amount to add to the count
+     */
+    public void add(final long delta)
+    {
+        long value=_curr.addAndGet(delta);
+        if (delta > 0)
+            _total.addAndGet(delta);
+        Atomics.updateMax(_max,value);
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @param delta the amount to subtract the count by.
+     */
+    public void subtract(final long delta)
+    {
+        add(-delta);
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     */
+    public void increment()
+    {
+        add(1);
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     */
+    public void decrement()
+    {
+        add(-1);
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @return max value
+     */
+    public long getMax()
+    {
+        return _max.get();
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @return current value
+     */
+    public long getCurrent()
+    {
+        return _curr.get();
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @return total value
+     */
+    public long getTotal()
+    {
+        return _total.get();
+    }
+}