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diff --git a/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/util/SizeOf.java b/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/util/SizeOf.java
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+++ b/qpid/java/junit-toolkit/src/main/org/apache/qpid/junit/extensions/util/SizeOf.java
@@ -0,0 +1,94 @@
+/*
+ *
+ * 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.util;
+
+/**
+ * SizeOf provides a static method that does its best to return an accurate measure of the total amount of memory used by
+ * the virtual machine. This is calculated as the total memory available to the VM minus the actual amount used by it.
+ * Before this measurement is taken the garbage collector is run many times until the used memory calculation stabilizes.
+ * Generally, this trick works quite well to provide an accurate reading, however, it cannot be relied upon to be totally
+ * accurate. It is also quite slow.
+ *
+ * <p><table id="crc"><caption>CRC Card</caption>
+ * <tr><th> Responsibilities <th> Collaborations
+ * <tr><td> Calculate total memory used.
+ * </table>
+ *
+ * @author Rupert Smith
+ */
+public class SizeOf
+{
+    /** Holds a reference to the runtime object. */
+    private static final Runtime RUNTIME = Runtime.getRuntime();
+
+    /**
+     * Makes 4 calls the {@link #runGCTillStable} method.
+     */
+    public static void runGCTillStableSeveralTimes()
+    {
+        // It helps to call Runtime.gc() using several method calls.
+        for (int r = 0; r < 4; ++r)
+        {
+            runGCTillStable();
+        }
+    }
+
+    /**
+     * Runs the garbage collector until the used memory reading stabilizes. It may run the garbage collector up
+     * to 500 times.
+     */
+    public static void runGCTillStable()
+    {
+        long usedMem1 = usedMemory(), usedMem2 = Long.MAX_VALUE;
+
+        for (int i = 0; (usedMem1 < usedMem2) && (i < 500); ++i)
+        {
+            RUNTIME.runFinalization();
+            RUNTIME.gc();
+            Thread.currentThread().yield();
+
+            usedMem2 = usedMem1;
+            usedMem1 = usedMemory();
+        }
+    }
+
+    /**
+     * Runs the garbage collector until the used memory stabilizes and then measures it.
+     *
+     * @return The amount of memory used by the virtual machine.
+     */
+    public static long getUsedMemory()
+    {
+        runGCTillStableSeveralTimes();
+
+        return usedMemory();
+    }
+
+    /**
+     * Returns the amount of memory used by subtracting the free memory from the total available memory.
+     *
+     * @return The amount of memory used.
+     */
+    private static long usedMemory()
+    {
+        return RUNTIME.totalMemory() - RUNTIME.freeMemory();
+    }
+}