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 
  28 package com.sun.org.glassfish.external.statistics.impl;
  29 import com.sun.org.glassfish.external.statistics.RangeStatistic;
  30 import java.util.Map;
  31 import java.lang.reflect.*;
  32 
  33 /**
  34  * @author Sreenivas Munnangi
  35  */
  36 public 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 }