source4/lib/appweb/ejs-2.0/ejs/lib/timer.js

   1 /*
   2  *      @file   timer.js
   3  *      @brief  Timer class
   4  *      @copy   Copyright (c) Mbedthis Software LLC, 2005-2006. All Rights Reserved.
   5  *
   6  *      Usage:
   7  *              timer = new System.Timer("name", period);
   8  *              timer.onTick = function(arg) {
   9  *                      //      Anything here
  10  *              }
  11  *              timer.start();
  12  *      or
  13  *
  14  *              timer = new System.Timer("name", period, obj, method);
  15  *              timer.start();
  16  */
  17
  18 /******************************************************************************/
  19
  20 class System.Timer
  21 {
  22         var             id;
  23
  24         /* MOB -- really need accessor on period. If user updates period,
  25                 then due must be updated. */
  26         var             period;
  27         var             due;
  28         var             runOnce;                                        // Run timer just once
  29         var             method;                                         // Callback method
  30         var             obj;                                            // Callback object
  31
  32         function Timer(id, period, obj, method)
  33         {
  34                 this.id = id;
  35                 this.period = period;
  36                 due = time() + period;
  37
  38                 if (arguments.length >= 3) {
  39                         this.obj = obj;
  40                 } else {
  41                         this.obj = this;
  42                 }
  43                 if (arguments.length >= 4) {
  44                         this.method = method;
  45                 } else {
  46                         this.method = "onTick";
  47                 }
  48         }
  49
  50         /* MOB this should be deprecated */
  51         function reschedule(period)
  52         {
  53                 /* MOB -- should update the timer service somehow */
  54                 this.period = period;
  55         }
  56
  57         function run(now)
  58         {
  59                 if (obj[method] == undefined) {
  60                         trace("Timer cant find timer method " + method);
  61                         due = now + this.period;
  62                         return;
  63                 }
  64
  65                 /*
  66                  *      Run the timer
  67                  */
  68                 try {
  69                         obj[method](this);
  70                 }
  71                 catch (error) {
  72                         trace("Timer exception: " + error);
  73                 }
  74
  75                 if (runOnce) {
  76                         timerService.removeTimer(this);
  77
  78                 } else {
  79                         due = now + this.period;
  80                 }
  81         }
  82
  83         function start()
  84         {
  85                 if (obj[method] == undefined) {
  86                         throw new Error("Callback method is undefined");
  87                 } else {
  88                         timerService.addTimer(this);
  89                 }
  90         }
  91
  92         function stop()
  93         {
  94                 timerService.removeTimer(this);
  95         }
  96
  97 }
  98
  99 /* MOB -- should not need this */
 100 Timer = System.Timer;
 101
 102
 103 /*
 104  *      Timer service
 105  */
 106 class System.TimerService
 107 {
 108         var             timers;
 109         var             nextDue;
 110
 111         function TimerService()
 112         {
 113                 timers = new Object();
 114                 nextDue = 0;
 115                 global.timerService = this;
 116         }
 117
 118         function addTimer(timer)
 119         {
 120                 timers[timer.id] = timer;
 121         }
 122
 123         function removeTimer(timer)
 124         {
 125                 try {
 126                         delete timers[timer.id];
 127                 }
 128                 catch {}
 129         }
 130
 131         function getIdleTime()
 132         {
 133                 return nextDue - time();
 134         }
 135
 136         function runTimers()
 137         {
 138                 var             now = time();
 139
 140                 nextDue = 2147483647;           /* MOB -- MATH.MAX_INT; */
 141
 142                 for each (var timer in timers)
 143                 {
 144                         if (timer.due < now) {
 145                                 timer.run(now);
 146                         }
 147                 }
 148                 for each (var timer in timers)
 149                 {
 150                         if (timer.due < nextDue) {
 151                                 nextDue = timer.due;
 152                         }
 153                 }
 154                 // println("runTimers leaving with " + (nextDue - now));
 155                 return nextDue - time();
 156         }
 157 }
 158 TimerService = System.TimerService;