1/*
2 * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26
27
28package com.sun.org.glassfish.external.statistics.impl;
29import com.sun.org.glassfish.external.statistics.RangeStatistic;
30import java.util.Map;
31import java.lang.reflect.*;
32
33/**
34 * @author Sreenivas Munnangi
35 */
36public final class RangeStatisticImpl extends StatisticImpl
37    implements RangeStatistic, InvocationHandler {
38
39    private long currentVal = 0L;
40    private long highWaterMark = Long.MIN_VALUE;
41    private long lowWaterMark = Long.MAX_VALUE;
42    private final long initCurrentVal;
43    private final long initHighWaterMark;
44    private final long initLowWaterMark;
45
46    private final RangeStatistic rs =
47            (RangeStatistic) Proxy.newProxyInstance(
48            RangeStatistic.class.getClassLoader(),
49            new Class[] { RangeStatistic.class },
50            this);
51
52    public RangeStatisticImpl(long curVal, long highMark, long lowMark,
53                              String name, String unit, String desc,
54                              long startTime, long sampleTime) {
55        super(name, unit, desc, startTime, sampleTime);
56        currentVal = curVal;
57        initCurrentVal = curVal;
58        highWaterMark = highMark;
59        initHighWaterMark = highMark;
60        lowWaterMark = lowMark;
61        initLowWaterMark = lowMark;
62    }
63
64    public synchronized RangeStatistic getStatistic() {
65        return rs;
66    }
67
68    public synchronized Map getStaticAsMap() {
69        Map m = super.getStaticAsMap();
70        m.put("current", getCurrent());
71        m.put("lowwatermark", getLowWaterMark());
72        m.put("highwatermark", getHighWaterMark());
73        return m;
74    }
75
76    public synchronized long getCurrent() {
77        return currentVal;
78    }
79
80    public synchronized void setCurrent(long curVal) {
81        currentVal = curVal;
82        lowWaterMark = (curVal >= lowWaterMark ? lowWaterMark : curVal);
83        highWaterMark = (curVal >= highWaterMark ? curVal : highWaterMark);
84        sampleTime = System.currentTimeMillis();
85    }
86
87    /**
88     * Returns the highest value of this statistic, since measurement started.
89     */
90    public synchronized long getHighWaterMark() {
91        return highWaterMark;
92    }
93
94    public synchronized void setHighWaterMark(long hwm) {
95        highWaterMark = hwm;
96    }
97
98    /**
99     * Returns the lowest value of this statistic, since measurement started.
100     */
101    public synchronized long getLowWaterMark() {
102        return lowWaterMark;
103    }
104
105    public synchronized void setLowWaterMark(long lwm) {
106        lowWaterMark = lwm;
107    }
108
109    @Override
110    public synchronized void reset() {
111        super.reset();
112        currentVal = initCurrentVal;
113        highWaterMark = initHighWaterMark;
114        lowWaterMark = initLowWaterMark;
115        sampleTime = -1L;
116    }
117
118    public synchronized String toString() {
119        return super.toString() + NEWLINE +
120            "Current: " + getCurrent() + NEWLINE +
121            "LowWaterMark: " + getLowWaterMark() + NEWLINE +
122            "HighWaterMark: " + getHighWaterMark();
123    }
124
125    // todo: equals implementation
126    public Object invoke(Object proxy, Method m, Object[] args) throws Throwable {
127        checkMethod(m);
128
129        Object result;
130        try {
131            result = m.invoke(this, args);
132        } catch (InvocationTargetException e) {
133            throw e.getTargetException();
134        } catch (Exception e) {
135            throw new RuntimeException("unexpected invocation exception: " +
136                       e.getMessage());
137        }
138        return result;
139    }
140}
141