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diff --git a/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/BaseThrottle.java b/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/BaseThrottle.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;
+
+/**
+ * Provides a base implementation of the non-waiting throttle checking method, using the system nano timer.
+ *
+ * <p/><table id="crc"><caption>CRC Card</caption>
+ * <tr><th> Responsibilities <th> Collaborations
+ * <tr><td> Check against a throttle speed without waiting.
+ * </table>
+ *
+ * @author Rupert Smith
+ */
+public abstract class BaseThrottle implements Throttle
+{
+    /** Holds the length of a single cycle in nano seconds. */
+    protected long cycleTimeNanos;
+
+    /** Holds the time of the last succesfull call to the check method. */
+    private long lastCheckTimeNanos;
+
+    /** Flag used to detect the first call to the {@link #checkThrottle()} method. */
+    boolean firstCheckCall = true;
+
+    /**
+     * Flag used to detect the first call to the {@link #throttle()} method. Zero or negative start time cannot be
+     * relied on to detect this as System.nanoTime can return zero or negative values.
+     */
+    boolean firstCall = true;
+
+    /**
+     * Specifies the throttling rate in operations per second. This must be called with with a value, the inverse
+     * of which is a measurement in nano seconds, such that the number of nano seconds do not overflow a long integer.
+     * The value must also be larger than zero.
+     *
+     * @param hertz The throttling rate in cycles per second.
+     */
+    public void setRate(float hertz)
+    {
+        // Check that the argument is above zero.
+        if (hertz <= 0.0f)
+        {
+            throw new IllegalArgumentException("The throttle rate must be above zero.");
+        }
+
+        // Calculate the cycle time.
+        cycleTimeNanos = (long) (1000000000f / hertz);
+
+        // Reset the first pass flag.
+        firstCall = false;
+        firstCheckCall = false;
+    }
+
+    /**
+     * Checks but does not enforce the throttle rate. When this method is called, it checks if a length of time greater
+     * than that equal to the inverse of the throttling rate has passed since it was last called and returned <tt>true</tt>
+     *
+     * @return <tt>true</tt> if a length of time greater than that equal to the inverse of the throttling rate has
+     *         passed since this method was last called and returned <tt>true</tt>, <tt>false</tt> otherwise. The very
+     *         first time this method is called on a throttle, it returns <tt>true</tt> as the base case to the above
+     *         self-referential definition.
+     */
+    public boolean checkThrottle()
+    {
+        long now = System.nanoTime();
+
+        if ((now > (cycleTimeNanos + lastCheckTimeNanos)) || firstCheckCall)
+        {
+            firstCheckCall = false;
+            lastCheckTimeNanos = now;
+
+            return true;
+        }
+        else
+        {
+            return false;
+        }
+    }
+}