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diff --git a/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/Throttle.java b/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/Throttle.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;
+
+/**
+ * Throttle is an interface that supplies a {@link #throttle} method, that can only be called at the rate specified
+ * in a call to the {@link #setRate} method. This can be used to restict processing to run at a certain number
+ * of operations per second.
+ *
+ * <p/>Throttle also supplies a method to check the throttle rate, without waiting. This could be used to update a user
+ * interface every time an event occurs, but only up to a maximum rate. For example, as elements are added to a list,
+ * a count of elements is updated for the user to see, but only up to a maximum rate of ten updates a second, as updating
+ * faster than that slows the processing of element-by-element additions to the list unnecessarily.
+ *
+ * <p/><table id="crc"><caption>CRC Card</caption>
+ * <tr><th> Responsibilities
+ * <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 interface Throttle
+{
+    /**
+     * 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);
+
+    /**
+     * 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.
+     *
+     * <p/>If the thread executing this method is interrupted, it must ensure that the threads interrupt thread
+     * remains set upon exit from the method. This method does not expose InterruptedException, to indicate interruption
+     * of the throttle during a timed wait. It may be changed so that it does.
+     */
+    public void throttle();
+
+    /**
+     * 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();
+}