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diff --git a/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/BatchedThrottle.java b/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/BatchedThrottle.java
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+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+package org.apache.qpid.junit.extensions;
+
+/**
+ * BatchedThrottle is a {@link SleepThrottle} that uses batching to achieve much higher throttling rates than a sleep
+ * throttle can. Sleep throttle has difficulties once the rate gets above a few hundred hertz, because the JVM cannot
+ * generate timed pauses that are that short. BatchedThrottle gets around this by only inserting pauses once every so
+ * many calls to the {@link #throttle()} method, and using a sleep throttle run at a lower rate. The rate for the sleep
+ * throttle is chosen so that it remains under 100hz. The final throttling rate of this throttle is equal to the batch
+ * size times the rate of the underlying sleep throttle.
+ *
+ * <p/>The batching calculation involves taking the log to the base 100 of the desired rate and rounding this to
+ * an integer. The batch size is always an exact power of 100 because of the rounding. The rate for an underlying
+ * sleep throttle is then chosen appropriately.
+ *
+ * <p/>In practice, the accuracy of a BacthedThrottle skews off but can sometimes even be reasonable up to ten thousand
+ * hertz compared with 100 Hz for a {@link SleepThrottle}.
+ *
+ * <p><table id="crc"><caption>CRC Card</caption>
+ * <tr><th> Responsibilities <th> Collaborations
+ * <tr><td> Accept throttling rate in operations per second.
+ * <tr><td> Inject short pauses, occasionaly, to fill out processing cycles to a specified rate.
+ * <tr><td> Check against a throttle speed without waiting.
+ * </table>
+ *
+ * @todo Should always round the log base 100 down to the nearest integer?
+ *
+ * @author Rupert Smith
+ */
+public class BatchedThrottle extends BaseThrottle
+{
+    /** Holds the batch size. */
+    int batchSize;
+
+    /** The call count within the current batch. */
+    long callCount;
+
+    /** Holds a sleep throttle configured to run at the batched rate. */
+    private Throttle batchRateThrottle = new SleepThrottle();
+
+    /**
+     * Specifies the throttling rate in operations per second.
+     *
+     * @param hertz The throttling rate in cycles per second.
+     */
+    public void setRate(float hertz)
+    {
+        // Pass the rate unaltered down to the base implementation, for the check method.
+        super.setRate(hertz);
+
+        // Log base 10 over 2 is used here to get a feel for what power of 100 the total rate is.
+        // As the total rate goes up the powers of 100 the batch size goes up by powers of 100 to keep the
+        // throttle rate in the range 1 to 100.
+        int x = (int) (Math.log10(hertz) / 2);
+        batchSize = (int) Math.pow(100, x);
+        float throttleRate = hertz / batchSize;
+
+        // Reset the call count.
+        callCount = 0;
+
+        // Set the sleep throttle wrapped implementation at a rate within its abilities.
+        batchRateThrottle.setRate(throttleRate);
+    }
+
+    /**
+     * Throttle calls to this method to the rate specified by the {@link #setRate(float)} method.
+     */
+    public void throttle()
+    {
+        if ((callCount++ % batchSize) == 0)
+        {
+            batchRateThrottle.throttle();
+        }
+    }
+}