org.eclipse.linuxtools.lttng.ui/src/org/eclipse/linuxtools/lttng/ui/views/histogram/HistogramRequest.java

   1 /*******************************************************************************
   2  * Copyright (c) 2009 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   William Bourque - Initial API and implementation
  11  *
  12  * Modifications:
  13  * 2010-07-16 Yuriy Vashchuk - Heritage correction.
  14  *******************************************************************************/
  15 package org.eclipse.linuxtools.lttng.ui.views.histogram;
  16
  17 import org.eclipse.linuxtools.lttng.event.LttngEvent;
  18 import org.eclipse.linuxtools.tmf.event.TmfTimeRange;
  19 import org.eclipse.linuxtools.tmf.request.ITmfDataRequest;
  20 import org.eclipse.linuxtools.tmf.request.TmfEventRequest;
  21
  22 /**
  23  * <b><u>HistogramRequest</u></b>
  24  * <p>
  25  * Request class, to perform a request to TMF for the histograms.
  26  * <p>
  27  */
  28 public class HistogramRequest extends TmfEventRequest<LttngEvent> {
  29 /*
  30         private HistogramContent histogramContent = null;
  31 */
  32
  33         private int     lastInterval = 0;
  34         private long    lastRangeTime = 0L;
  35         private long    nbEventsInInterval = 0L;
  36
  37         private int     nbIntervalNotEmpty = 1;
  38         private int     nbEventRead = 0;
  39
  40         private int     lastDrawPosition = 0;
  41
  42         private HistogramCanvas parentCanvas = null;
  43
  44         private boolean isCompleted = false;
  45
  46         /**
  47          * Constructor for HistogramRequest.<p>
  48          * Prepare the request in TMF and reset the histogram content.
  49          *
  50          * @param range                         Range of the request.
  51          * @param nbRequested           Nb events requested. Can be "Infinity" for all.
  52          * @param newParentCanvas       HistogramCanvas related to the request.
  53          * @param timeInterval          Time interval to consider (i.e. : 1 interval is 1 bar in the histogram)
  54          *
  55          * @see org.eclipse.linuxtools.tmf.request.TmfEventRequest
  56          */
  57         public HistogramRequest(TmfTimeRange range, int nbRequested, HistogramCanvas newParentCanvas, long timeInterval, ITmfDataRequest.ExecutionType execType) {
  58         super((Class<LttngEvent>)LttngEvent.class, range, nbRequested, HistogramConstant.MAX_EVENTS_PER_READ, execType);
  59
  60         setIsCompleted(false);
  61
  62         // *** FIXME ***
  63         // This does not work! The request won't be processed or the number of events returned is wrong!
  64         // We cannot use this !
  65                 //super((Class<LttngEvent>)dataType, range);
  66
  67         parentCanvas = newParentCanvas;
  68
  69         // Reset the content of the HistogramContent... the given data better be valid or this will fail.
  70         parentCanvas.getHistogramContent().clearContentData();
  71         parentCanvas.getHistogramContent().resetTable(range.getStartTime().getValue(), range.getEndTime().getValue(), timeInterval);
  72
  73         lastRangeTime = range.getStartTime().getValue();
  74
  75         // Notify the UI even before the request started, so we set the timestamp already.
  76         parentCanvas.notifyParentUpdatedInformationAsynchronously();
  77     }
  78
  79         /**
  80          * HandleData function : will be called by TMF each time a new event is receive for the request.<p>
  81          * Calculation for the content is done here.
  82          */
  83         @Override
  84     public void handleData() {
  85         LttngEvent[] result = getData();
  86         LttngEvent event = (result.length > 0) ? result[0] : null;
  87
  88         // *** FIXME ***
  89         // *** EVIL BUG ***
  90         // The request by timerange only does not work! (see constructor above)
  91         //      However, the request with number of events will loop until it reach its number or EOF
  92         //  We have to filter out ourself the extra useless events!
  93         //
  94         if (event != null) {
  95
  96                 LttngEvent tmpEvent = (LttngEvent) event;
  97
  98 //                      Tracer.trace("Hst: " + event.getTimestamp());
  99
 100                 // This check is linked to the evil fix mentionned above
 101                 if ( ( tmpEvent.getTimestamp().getValue() >= parentCanvas.getHistogramContent().getStartTime() ) &&
 102                          ( tmpEvent.getTimestamp().getValue() <= parentCanvas.getHistogramContent().getEndTime() ) )
 103                 {
 104
 105                         // Distance (in time) between this event and the last one we read
 106                         long distance = ( tmpEvent.getTimestamp().getValue() - lastRangeTime );
 107
 108                         // Check if we changed of interval (the distance is higher than the interval time)
 109                                 if  ( distance > parentCanvas.getHistogramContent().getElementsTimeInterval() ) {
 110
 111                                         parentCanvas.getHistogramContent().getElementByIndex(lastInterval).intervalNbEvents = nbEventsInInterval;
 112                                         lastRangeTime = tmpEvent.getTimestamp().getValue();
 113
 114                                         // * NOTE *
 115                                         // We can skip several interval at once, so we need to find what was our interval now
 116                                         lastInterval = (int)((lastRangeTime - parentCanvas.getHistogramContent().getStartTime()) / parentCanvas.getHistogramContent().getElementsTimeInterval() );
 117
 118                                         // *** HACK ***
 119                                         // Because of the threads, weird phenomenons seem to happen here, like a position after the
 120                                         //       element range because another request was issued.
 121                                         // This enforce the position but may result in slightly inconsistent result (i.e. a weird misplaced bar sometime).
 122                                         if ( lastInterval < 0 ) {
 123                                                 lastInterval = 0;
 124                                         }
 125                                         else if ( lastInterval >= parentCanvas.getHistogramContent().getNbElement() ) {
 126                                                 lastInterval = (parentCanvas.getHistogramContent().getNbElement()-1);
 127                                         }
 128
 129                                         // * NOTE *
 130                                         // We save the time we have here. This mean only the FIRST time read in an interval will be saved.
 131                                         parentCanvas.getHistogramContent().getElementByIndex(lastInterval).firstIntervalTimestamp = lastRangeTime;
 132                                         parentCanvas.getHistogramContent().setReadyUpToPosition(lastInterval);
 133
 134                                         nbIntervalNotEmpty++;
 135                                         nbEventsInInterval = 1L;
 136                                 }
 137                                 // We are still in the same interval, just keep counting
 138                                 else {
 139                                         nbEventsInInterval++;
 140                                 }
 141
 142                                 if ( nbEventsInInterval > parentCanvas.getHistogramContent().getHeighestEventCount() ) {
 143                                         parentCanvas.getHistogramContent().setHeighestEventCount(nbEventsInInterval);
 144                                 }
 145                                 nbEventRead++;
 146
 147                                 // Call an asynchronous redraw every REDRAW_EVERY_NB_EVENTS events
 148                                 // That way we don't need to wait until to end to have something on the screen
 149                                 if ( nbEventRead % HistogramConstant.REDRAW_EVERY_NB_EVENTS == 0 ) {
 150                                         redrawAsyncronously();
 151                                 }
 152                 }
 153                 }
 154         // We got a null event! This mean we reach the end of the request.
 155         // Save the last interval we had, so we won't miss the very last events at the end.
 156         else {
 157                 // Save the last events
 158                 parentCanvas.getHistogramContent().getElementByIndex(lastInterval).intervalNbEvents = nbEventsInInterval;
 159                 // We reached the end of the request, so assume we fill up the content as well
 160                 parentCanvas.getHistogramContent().setReadyUpToPosition(parentCanvas.getHistogramContent().getNbElement());
 161
 162                         // If the interval wasn't null, count this as a "non empty" interval
 163                         if (nbEventsInInterval > 0) {
 164                                 nbIntervalNotEmpty++;
 165                         }
 166         }
 167     }
 168
 169         /**
 170          * Function that is called when the request completed (successful or not).<p>
 171          * Update information and redraw the screen.
 172          */
 173     @Override
 174     public void handleCompleted() {
 175         setIsCompleted(true);
 176         parentCanvas.notifyParentUpdatedInformationAsynchronously();
 177                 redrawAsyncronously();
 178                 super.handleCompleted();
 179 //              System.out.println(System.currentTimeMillis() + ": HistogramView (" + ((getExecType() == ExecutionType.LONG) ? "long" : "short") + ") completed");
 180     }
 181
 182 //    /**
 183 //       * Function that is called when the request completed successfully.<p>
 184 //       */
 185 //    @Override
 186 //    public void handleSuccess() {
 187 //      // Nothing different from completed.
 188 //    }
 189
 190 //    /**
 191 //       * Function that is called when the request completed in failure.<p>
 192 //       */
 193 //    @Override
 194 //    public void handleFailure() {
 195 //      // Nothing different from cancel.
 196 //    }
 197
 198     /**
 199          * Function that is called when the request was cancelled.<p>
 200          * Redraw and set the requestCompleted flag to true;
 201          */
 202     @Override
 203     public void handleCancel() {
 204         redrawAsyncronously();
 205     }
 206
 207     /**
 208          * Update the HistogramContent with the latest information.<p>
 209          * This will perform some calculation that might be a bit harsh so it should'nt be called too often.
 210          */
 211     public void updateEventsInfo() {
 212         // *** Note ***
 213         // The average number of event is calculated while skipping empty interval if asked
 214         int averageNumberOfEvents = 0;
 215         if ( HistogramConstant.SKIP_EMPTY_INTERVALS_WHEN_CALCULATING_AVERAGE ) {
 216                 averageNumberOfEvents = (int)Math.ceil((double)nbEventRead / (double)nbIntervalNotEmpty);
 217         }
 218         else {
 219                 averageNumberOfEvents = (int)Math.ceil((double)nbEventRead / (double)parentCanvas.getHistogramContent().getNbElement());
 220         }
 221
 222         parentCanvas.getHistogramContent().setAverageNumberOfEvents(averageNumberOfEvents);
 223
 224         // It is possible that the height factor didn't change;
 225         //              If not, we only need to redraw the updated section, no the whole content
 226         // Save the actual height, recalculate the height and check if there was any changes
 227         double previousHeightFactor = parentCanvas.getHistogramContent().getHeightFactor();
 228         parentCanvas.getHistogramContent().recalculateHeightFactor();
 229         if ( parentCanvas.getHistogramContent().getHeightFactor() != previousHeightFactor ) {
 230                 parentCanvas.getHistogramContent().recalculateEventHeight();
 231         }
 232         else {
 233                 parentCanvas.getHistogramContent().recalculateEventHeightInInterval(lastDrawPosition, parentCanvas.getHistogramContent().getReadyUpToPosition());
 234         }
 235
 236         lastDrawPosition = parentCanvas.getHistogramContent().getReadyUpToPosition();
 237     }
 238
 239     /**
 240          * Perform an asynchonous redraw of the screen.
 241          */
 242     public void redrawAsyncronously() {
 243         updateEventsInfo();
 244         // Canvas redraw is already asynchronous
 245         parentCanvas.redrawAsynchronously();
 246     }
 247
 248         /**
 249          * Getter for isCompleted variable
 250          * @return true if the request is completed
 251          */
 252         public boolean getIsCompleted() {
 253                 return isCompleted;
 254         }
 255
 256         /**
 257          * Setter for isCompleted variable
 258          * @param isCompleted value to set the completed flag
 259          */
 260         public void setIsCompleted(boolean isCompleted) {
 261                 this.isCompleted = isCompleted;
 262         }
 263
 264 }