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diff --git a/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/SleepThrottle.java b/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/SleepThrottle.java
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+++ b/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/SleepThrottle.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;
+
+/**
+ * SleepThrottle is a Throttle implementation that generates short pauses using the thread sleep methods. As the pauses
+ * get shorter, this technique gets more innacurate. In practice, around 100 Hz is the cap rate for accuracy.
+ *
+ * <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 to fill out processing cycles to a specified rate.
+ * <tr><td> Check against a throttle speed without waiting.
+ * </table>
+ *
+ * @author Rupert Smith
+ */
+public class SleepThrottle extends BaseThrottle implements Throttle
+{
+    /** Holds the time of the last call to the throttle method in nano seconds. */
+    private long lastTimeNanos;
+
+    /**
+     * This method can only be called at the rate set by the {@link #setRate} method, if it is called faster than this
+     * it will inject short pauses to restrict the call rate to that rate.
+     */
+    public void throttle()
+    {
+        // Get the current time in nanos.
+        long currentTimeNanos = System.nanoTime();
+
+        // Don't introduce any pause on the first call.
+        if (!firstCall)
+        {
+            // Check if there is any time left in the cycle since the last call to this method and introduce a short pause
+            // to fill that time if there is.
+            long remainingTimeNanos = cycleTimeNanos - (currentTimeNanos - lastTimeNanos);
+
+            if (remainingTimeNanos > 0)
+            {
+                long milliPause = remainingTimeNanos / 1000000;
+                int nanoPause = (int) (remainingTimeNanos % 1000000);
+
+                try
+                {
+                    Thread.sleep(milliPause, nanoPause);
+                }
+                catch (InterruptedException e)
+                {
+                    // Restore the interrupted thread, in-case the caller is checking for it.
+                    Thread.currentThread().interrupt();
+                }
+            }
+        }
+        else
+        {
+            firstCall = false;
+        }
+
+        // Update the last time stamp.
+        lastTimeNanos = System.nanoTime();
+    }
+}