1 /*
   2  * Copyright (c) 1997, 2007, 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 package com.sun.org.glassfish.external.statistics.impl;
  27 import com.sun.org.glassfish.external.statistics.RangeStatistic;
  28 import java.util.concurrent.atomic.AtomicLong;
  29 import java.util.Map;
  30 import java.lang.reflect.*;
  31 
  32 /**
  33  * @author Sreenivas Munnangi
  34  */
  35 public final class RangeStatisticImpl extends StatisticImpl
  36     implements RangeStatistic, InvocationHandler {
  37 
  38     private long currentVal = 0L;
  39     private long highWaterMark = Long.MIN_VALUE;
  40     private long lowWaterMark = Long.MAX_VALUE;
  41     private final long initCurrentVal;
  42     private final long initHighWaterMark;
  43     private final long initLowWaterMark;
  44 
  45     private final RangeStatistic rs =
  46             (RangeStatistic) Proxy.newProxyInstance(
  47             RangeStatistic.class.getClassLoader(),
  48             new Class[] { RangeStatistic.class },
  49             this);
  50 
  51     public RangeStatisticImpl(long curVal, long highMark, long lowMark,
  52                               String name, String unit, String desc,
  53                               long startTime, long sampleTime) {
  54         super(name, unit, desc, startTime, sampleTime);
  55         currentVal = curVal;
  56         initCurrentVal = curVal;
  57         highWaterMark = highMark;
  58         initHighWaterMark = highMark;
  59         lowWaterMark = lowMark;
  60         initLowWaterMark = lowMark;
  61     }
  62 
  63     public synchronized RangeStatistic getStatistic() {
  64         return rs;
  65     }
  66 
  67     public synchronized Map getStaticAsMap() {
  68         Map m = super.getStaticAsMap();
  69         m.put("current", getCurrent());
  70         m.put("lowwatermark", getLowWaterMark());
  71         m.put("highwatermark", getHighWaterMark());
  72         return m;
  73     }
  74 
  75     public synchronized long getCurrent() {
  76         return currentVal;
  77     }
  78 
  79     public synchronized void setCurrent(long curVal) {
  80         currentVal = curVal;
  81         lowWaterMark = (curVal >= lowWaterMark ? lowWaterMark : curVal);
  82         highWaterMark = (curVal >= highWaterMark ? curVal : highWaterMark);
  83         sampleTime = System.currentTimeMillis();
  84     }
  85 
  86     /**
  87      * Returns the highest value of this statistic, since measurement started.
  88      */
  89     public synchronized long getHighWaterMark() {
  90         return highWaterMark;
  91     }
  92 
  93     public synchronized void setHighWaterMark(long hwm) {
  94         highWaterMark = hwm;
  95     }
  96 
  97     /**
  98      * Returns the lowest value of this statistic, since measurement started.
  99      */
 100     public synchronized long getLowWaterMark() {
 101         return lowWaterMark;
 102     }
 103 
 104     public synchronized void setLowWaterMark(long lwm) {
 105         lowWaterMark = lwm;
 106     }
 107 
 108     @Override
 109     public synchronized void reset() {
 110         super.reset();
 111         currentVal = initCurrentVal;
 112         highWaterMark = initHighWaterMark;
 113         lowWaterMark = initLowWaterMark;
 114         sampleTime = -1L;
 115     }
 116 
 117     public synchronized String toString() {
 118         return super.toString() + NEWLINE +
 119             "Current: " + getCurrent() + NEWLINE +
 120             "LowWaterMark: " + getLowWaterMark() + NEWLINE +
 121             "HighWaterMark: " + getHighWaterMark();
 122     }
 123 
 124     // todo: equals implementation
 125     public Object invoke(Object proxy, Method m, Object[] args) throws Throwable {
 126         Object result;
 127         try {
 128             result = m.invoke(this, args);
 129         } catch (InvocationTargetException e) {
 130             throw e.getTargetException();
 131         } catch (Exception e) {
 132             throw new RuntimeException("unexpected invocation exception: " +
 133                        e.getMessage());
 134         } finally {
 135         }
 136         return result;
 137     }
 138 }