org.eclipse.linuxtools.tmf/src/org/eclipse/linuxtools/tmf/trace/TmfTrace.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  *   Francois Chouinard - Initial API and implementation
  11  *******************************************************************************/
  12
  13 package org.eclipse.linuxtools.tmf.trace;
  14
  15 import java.util.HashSet;
  16 import java.util.Set;
  17 import java.util.Vector;
  18
  19 import org.eclipse.linuxtools.tmf.event.TmfEvent;
  20 import org.eclipse.linuxtools.tmf.event.TmfTimeRange;
  21 import org.eclipse.linuxtools.tmf.event.TmfTimestamp;
  22 import org.eclipse.linuxtools.tmf.request.ITmfRequestHandler;
  23 import org.eclipse.linuxtools.tmf.request.TmfDataRequest;
  24 import org.eclipse.linuxtools.tmf.stream.ITmfEventStream;
  25 import org.eclipse.linuxtools.tmf.stream.TmfStreamUpdateEvent;
  26 import org.eclipse.linuxtools.tmf.stream.ITmfEventStream.StreamContext;
  27
  28 /**
  29  * <b><u>TmfEventLog</u></b>
  30  * <p>
  31  * TmfEventLog represents a time-ordered set of events tied to a single event
  32  * stream. It keeps track of the global information about the event log:
  33  * <ul>
  34  * <li> the epoch, a reference timestamp for the whole log (t0)
  35  * <li> the span of the log i.e. the timestamps range
  36  * <li> the total number of events
  37  * </ul>
  38  * As an ITmfRequestHandler, it provides an implementation of process()
  39  * which handles event requests.
  40  * <p>
  41  * TODO: Handle concurrent and possibly overlapping requests in a way that
  42  * optimizes the stream access and event parsing.
  43  */
  44 public class TmfTrace implements ITmfRequestHandler<TmfEvent> {
  45
  46     // ========================================================================
  47     // Attributes
  48     // ========================================================================
  49
  50         private final String fId;
  51     private final ITmfEventStream fStream;
  52     private final TmfTimestamp fEpoch;
  53
  54     // The listeners
  55     private Set<ITmfTraceEventListener> fListeners = new HashSet<ITmfTraceEventListener>();
  56
  57     // ========================================================================
  58     // Constructors/Destructors
  59     // ========================================================================
  60
  61     public TmfTrace(String id, ITmfEventStream stream) {
  62         this(id, stream, TmfTimestamp.BigBang);
  63     }
  64
  65     public TmfTrace(String id, ITmfEventStream stream, TmfTimestamp epoch) {
  66         assert stream != null;
  67         fId = id;
  68         fStream = stream;
  69         fEpoch = epoch;
  70         fStream.addListener(this);
  71     }
  72
  73     public void dispose() {
  74         fStream.removeListener(this);
  75     }
  76
  77     // ========================================================================
  78     // Accessors
  79     // ========================================================================
  80
  81     public String getId() {
  82         return fId;
  83     }
  84
  85     public ITmfEventStream getStream() {
  86         return fStream;
  87     }
  88
  89     public TmfTimestamp getEpoch() {
  90         return fEpoch;
  91     }
  92
  93     public TmfTimeRange getTimeRange() {
  94         return fStream.getTimeRange();
  95     }
  96
  97     public int getNbEvents() {
  98         return fStream.getNbEvents();
  99     }
 100
 101     // ========================================================================
 102     // Operators
 103     // ========================================================================
 104
 105     /* (non-Javadoc)
 106      * @see org.eclipse.linuxtools.tmf.eventlog.ITmfRequestHandler#processRequest(org.eclipse.linuxtools.tmf.eventlog.TmfDataRequest, boolean)
 107      */
 108     public void processRequest(TmfDataRequest<TmfEvent> request, boolean waitForCompletion) {
 109         if (request.getRange() != null) {
 110                 serviceEventRequestByTimestamp(request);
 111         } else {
 112                 serviceEventRequestByIndex(request);
 113         }
 114         if (waitForCompletion) {
 115             request.waitForCompletion();
 116         }
 117     }
 118
 119         public void addListener(ITmfTraceEventListener listener) {
 120                 fListeners.add(listener);
 121         }
 122
 123         public void removeListener(ITmfTraceEventListener listener) {
 124                 fListeners.remove(listener);
 125         }
 126
 127         public void handleEvent(TmfStreamUpdateEvent event) {
 128         for (ITmfTraceEventListener listener : fListeners) {
 129                 listener.handleEvent(new TmfTraceUpdateEvent(this));
 130         }
 131     }
 132
 133     // ========================================================================
 134     // Helper functions
 135     // ========================================================================
 136
 137     /* (non-Javadoc)
 138      *
 139      * @param request
 140      */
 141     private void serviceEventRequestByTimestamp(final TmfDataRequest<TmfEvent> request) {
 142         Thread thread = new Thread() {
 143             @Override
 144             public void run() {
 145                 TmfTimestamp startTime = request.getRange().getStartTime();
 146                 TmfTimestamp endTime   = request.getRange().getEndTime();
 147                 int blockSize = request.getBlockize();
 148
 149                 int nbRequestedEvents = request.getNbRequestedItems();
 150                 if (nbRequestedEvents == -1) {
 151                     nbRequestedEvents = Integer.MAX_VALUE;
 152                 }
 153
 154                 Vector<TmfEvent> events = new Vector<TmfEvent>();
 155                 int nbEvents = 0;
 156
 157                 StreamContext context = new StreamContext(null);
 158                 TmfEvent event = fStream.getEvent(context, startTime);
 159
 160                 while (!request.isCancelled() && nbEvents < nbRequestedEvents && event != null &&
 161                         event.getTimestamp().compareTo(endTime, false) <= 0 )
 162                 {
 163                     events.add(event);
 164                     if (++nbEvents % blockSize == 0) {
 165                         TmfEvent[] result = new TmfEvent[events.size()];
 166                         events.toArray(result);
 167                         request.setData(result);
 168                         request.handlePartialResult();
 169                         events.removeAllElements();
 170                     }
 171                     // To avoid an unnecessary read passed the last event requested
 172                     if (nbEvents < nbRequestedEvents)
 173                         event = fStream.getNextEvent(context);
 174                 }
 175                 TmfEvent[] result = new TmfEvent[events.size()];
 176                 events.toArray(result);
 177                 request.setData(result);
 178
 179                 request.handlePartialResult();
 180                 request.done();
 181             }
 182         };
 183         thread.start();
 184     }
 185
 186     /* (non-Javadoc)
 187      *
 188      * @param request
 189      */
 190     private void serviceEventRequestByIndex(final TmfDataRequest<TmfEvent> request) {
 191         Thread thread = new Thread() {
 192             @Override
 193             public void run() {
 194                 int blockSize = request.getBlockize();
 195
 196                 int nbRequestedEvents = request.getNbRequestedItems();
 197                 if (nbRequestedEvents == -1) {
 198                     nbRequestedEvents = Integer.MAX_VALUE;
 199                 }
 200
 201                 Vector<TmfEvent> events = new Vector<TmfEvent>();
 202                 int nbEvents = 0;
 203
 204                 StreamContext context = new StreamContext(null);
 205                 TmfEvent event = fStream.getEvent(context, request.getIndex());
 206
 207                 while (!request.isCancelled() && nbEvents < nbRequestedEvents && event != null)
 208                 {
 209                     events.add(event);
 210                     if (++nbEvents % blockSize == 0) {
 211                         TmfEvent[] result = new TmfEvent[events.size()];
 212                         events.toArray(result);
 213                         request.setData(result);
 214                         request.handlePartialResult();
 215                         events.removeAllElements();
 216                     }
 217                     // To avoid an unnecessary read passed the last event requested
 218                     if (nbEvents < nbRequestedEvents)
 219                         event = fStream.getNextEvent(context);
 220                 }
 221                 TmfEvent[] result = new TmfEvent[events.size()];
 222                 events.toArray(result);
 223
 224                 request.setData(result);
 225                 request.handlePartialResult();
 226                 request.done();
 227             }
 228         };
 229         thread.start();
 230     }
 231
 232 }