Added SizeStatisicsImpl for https://issues.apache.org/jira/browse/AMQ-4697

git-svn-id: https://svn.apache.org/repos/asf/activemq/trunk@1518217 13f79535-47bb-0310-9956-ffa450edef68

activemq-client/src/main/java/org/apache/activemq/management/SizeStatisticImpl.java

@@ -0,0 +1,168 @@
+/**
+ * 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.activemq.management;
+
+public class SizeStatisticImpl extends StatisticImpl{
+    private long count;
+    private long maxSize;
+    private long minSize;
+    private long totalSize;
+    private SizeStatisticImpl parent;
+
+    public SizeStatisticImpl(String name, String description) {
+        this(name, "bytes", description);
+    }
+
+    public SizeStatisticImpl(SizeStatisticImpl parent, String name, String description) {
+        this(name, description);
+        this.parent = parent;
+    }
+
+    public SizeStatisticImpl(String name, String unit, String description) {
+        super(name, unit, description);
+    }
+
+    public synchronized void reset() {
+        if(isDoReset()) {
+            super.reset();
+            count = 0;
+            maxSize = 0;
+            minSize = 0;
+            totalSize = 0;
+        }
+    }
+
+    public synchronized long getCount() {
+        return count;
+    }
+
+    public synchronized void addSize(long size) {
+        count++;
+        totalSize += size;
+        if (size > maxSize) {
+            maxSize = size;
+        }
+        if (size < minSize || minSize == 0) {
+            minSize = size;
+        }
+        updateSampleTime();
+        if (parent != null) {
+            parent.addSize(size);
+        }
+    }
+
+    /**
+     * @return the maximum time of any step
+     */
+    public long getMaxSize() {
+        return maxSize;
+    }
+
+    /**
+     * @return the minimum time of any step
+     */
+    public synchronized long getMinSize() {
+        return minSize;
+    }
+
+    /**
+     * @return the total time of all the steps added together
+     */
+    public synchronized long getTotalSize() {
+        return totalSize;
+    }
+
+    /**
+     * @return the average time calculated by dividing the
+     *         total time by the number of counts
+     */
+    public synchronized double getAverageSize() {
+        if (count == 0) {
+            return 0;
+        }
+        double d = totalSize;
+        return d / count;
+    }
+
+
+    /**
+     * @return the average time calculated by dividing the
+     *         total time by the number of counts but excluding the
+     *         minimum and maximum times.
+     */
+    public synchronized double getAverageSizeExcludingMinMax() {
+        if (count <= 2) {
+            return 0;
+        }
+        double d = totalSize - minSize - maxSize;
+        return d / (count - 2);
+    }
+
+
+    /**
+     * @return the average number of steps per second
+     */
+    public double getAveragePerSecond() {
+        double d = 1000;
+        double averageSize = getAverageSize();
+        if (averageSize == 0) {
+            return 0;
+        }
+        return d / averageSize;
+    }
+
+    /**
+     * @return the average number of steps per second excluding the min & max values
+     */
+    public double getAveragePerSecondExcludingMinMax() {
+        double d = 1000;
+        double average = getAverageSizeExcludingMinMax();
+        if (average == 0) {
+            return 0;
+        }
+        return d / average;
+    }
+
+    public SizeStatisticImpl getParent() {
+        return parent;
+    }
+
+    public void setParent(SizeStatisticImpl parent) {
+        this.parent = parent;
+    }
+
+    protected synchronized void appendFieldDescription(StringBuffer buffer) {
+        buffer.append(" count: ");
+        buffer.append(Long.toString(count));
+        buffer.append(" maxSize: ");
+        buffer.append(Long.toString(maxSize));
+        buffer.append(" minSize: ");
+        buffer.append(Long.toString(minSize));
+        buffer.append(" totalSize: ");
+        buffer.append(Long.toString(totalSize));
+        buffer.append(" averageTime: ");
+        buffer.append(Double.toString(getAverageSize()));
+        buffer.append(" averageTimeExMinMax: ");
+        buffer.append(Double.toString(getAveragePerSecondExcludingMinMax()));
+        buffer.append(" averagePerSecond: ");
+        buffer.append(Double.toString(getAveragePerSecond()));
+        buffer.append(" averagePerSecondExMinMax: ");
+        buffer.append(Double.toString(getAveragePerSecondExcludingMinMax()));
+        super.appendFieldDescription(buffer);
+    }
+
+}