bundles/org.simantics.history/src/org/simantics/history/util/StreamIterator.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2007, 2012 Association for Decentralized Information Management in\r
   3  * Industry THTH ry.\r
   4  * All rights reserved. This program and the accompanying materials\r
   5  * are made available under the terms of the Eclipse Public License v1.0\r
   6  * which accompanies this distribution, and is available at\r
   7  * http://www.eclipse.org/legal/epl-v10.html\r
   8  *\r
   9  * Contributors:\r
  10  *     VTT Technical Research Centre of Finland - initial API and implementation\r
  11  *******************************************************************************/\r
  12 package org.simantics.history.util;\r
  13 \r
  14 import org.simantics.databoard.Bindings;\r
  15 import org.simantics.databoard.accessor.ArrayAccessor;\r
  16 import org.simantics.databoard.accessor.error.AccessorException;\r
  17 import org.simantics.databoard.binding.Binding;\r
  18 import org.simantics.databoard.binding.RecordBinding;\r
  19 import org.simantics.databoard.binding.error.BindingException;\r
  20 import org.simantics.history.HistoryException;\r
  21 \r
  22 /**\r
  23  * Stream iterator iterates sample entries in an array.\r
  24  * \r
  25  * Is scans the next sample and knows its time stamp.\r
  26  * \r
  27  * @author toni.kalajainen\r
  28  */\r
  29 public class StreamIterator {\r
  30 \r
  31         // Sample binding\r
  32         RecordBinding sampleBinding;\r
  33         \r
  34         // Array accessor\r
  35         ArrayAccessor aa;\r
  36         // Array stream\r
  37         Stream stream;\r
  38         // From and end times of the whole stream\r
  39         double from, end;\r
  40         \r
  41         // Current and next sample\r
  42         Object current, next;\r
  43 \r
  44         // Utility for reading sample\r
  45         ValueBand valueBand, nextValueBand;\r
  46         // Start and end time of current sample\r
  47         double startTime, endTime;\r
  48         \r
  49         int index = -1;\r
  50         int size;\r
  51         \r
  52         public StreamIterator(ArrayAccessor aa) throws HistoryException {\r
  53                 try {\r
  54                         this.aa = aa;\r
  55                         sampleBinding = (RecordBinding) Bindings.getBeanBinding( aa.type().componentType );\r
  56                         current = sampleBinding.createDefault();\r
  57                         next = sampleBinding.createDefault();\r
  58                         valueBand = new ValueBand(sampleBinding, current);\r
  59                         nextValueBand = new ValueBand(sampleBinding, next);\r
  60                         stream = new Stream( aa, sampleBinding );\r
  61                         size = aa.size();\r
  62                         if ( size>0 ) {\r
  63                         aa.get(0, sampleBinding, current);\r
  64                                 from = valueBand.getTimeDouble();\r
  65                         aa.get(size-1, sampleBinding, current);\r
  66                                 end = valueBand.hasEndTime() ? valueBand.getEndTimeDouble() : valueBand.getTimeDouble();\r
  67                         }\r
  68                 } catch (BindingException e) {\r
  69                         throw new HistoryException( e );\r
  70                 } catch (AccessorException e) {\r
  71                         throw new HistoryException( e );\r
  72                 } \r
  73         }\r
  74         \r
  75         /**\r
  76          * Go to time using random access\r
  77          * @param time\r
  78          * @return true if sample was found\r
  79          * @throws HistoryException \r
  80          */\r
  81         public boolean gotoTime(double time) throws HistoryException {\r
  82                 // Outside range\r
  83                 if ( time<from || time>end ) {\r
  84                         index = -1;\r
  85                         return false;\r
  86                 }\r
  87                 \r
  88                 // Already at cursor\r
  89                 if ( time>=startTime && time<endTime ) return hasValue();\r
  90                 int i = stream.binarySearch(Bindings.DOUBLE, time);\r
  91                 if (i>=0) {\r
  92                         gotoIndex( i );\r
  93                 } else {\r
  94                         int insertPos = -i-2;\r
  95                         if ( insertPos<0 || insertPos>=size ) {\r
  96                                 index = -1;\r
  97                         } else {\r
  98                                 gotoIndex( insertPos );\r
  99                                 if ( endTime<time ) index = -1;\r
 100                         }\r
 101                 }\r
 102                 \r
 103                 return hasValue();              \r
 104         }\r
 105         \r
 106         /**\r
 107          * Proceed to time using sequential seek.\r
 108          * \r
 109          * @param time\r
 110          * @return true if sample was found\r
 111          * @throws HistoryException \r
 112          */\r
 113         public boolean proceedToTime(double time) throws HistoryException {\r
 114                 // Outside range\r
 115                 if ( time<from || time>end ) {\r
 116                         index = -1;\r
 117                         return false;\r
 118                 }\r
 119 \r
 120                 // No position, or going to past\r
 121                 if (index<0 || startTime>time) {\r
 122                         gotoTime(time);\r
 123                         return hasValue();\r
 124                 }\r
 125                 \r
 126                 // Proceed until end hit\r
 127                 while (time>=endTime && hasNext()) gotoIndex(index+1);\r
 128                 return hasValue();\r
 129         }\r
 130         \r
 131         /**\r
 132          * Go to index. If element does not exist, index is set to -1;\r
 133          * @param pos\r
 134          * @throws HistoryException\r
 135          */\r
 136         public void gotoIndex(int pos) throws HistoryException {\r
 137                 if (pos == index) return;\r
 138                 \r
 139                 if (pos<0 || pos>=size) {\r
 140                         index = -1;\r
 141                         return;\r
 142                 }\r
 143 \r
 144                 try {\r
 145                         // Read current value\r
 146                         if (pos == index+1 && index>=0) {\r
 147                                 sampleBinding.readFrom(sampleBinding, next, current);\r
 148                         } else {\r
 149                                 aa.get(pos, sampleBinding, current);\r
 150                         }\r
 151                         startTime = valueBand.getTimeDouble();\r
 152                         \r
 153                         // Read next value\r
 154                         if (pos+1<size) {\r
 155                                 aa.get(pos+1, sampleBinding, next);\r
 156                                 //endTime = valueBand.isValidValue() ? nextValueBand.getTimeDouble() : ( nextValueBand.isValidValue() ? nextValueBand.getTimeDouble() : nextValueBand.getTimeDouble() );\r
 157                                 endTime = nextValueBand.getTimeDouble();\r
 158                         } else {                                \r
 159                                 endTime = valueBand.hasEndTime() ? valueBand.getEndTimeDouble() : valueBand.getTimeDouble();\r
 160                         }\r
 161                         \r
 162                         // \r
 163                         index = pos;\r
 164                 } catch (AccessorException e) {\r
 165                         throw new HistoryException( e );\r
 166                 } catch (BindingException e) {\r
 167                         throw new HistoryException( e );\r
 168                 }\r
 169         }\r
 170 \r
 171         \r
 172         public boolean hasNext() {\r
 173                 return index<size-1;\r
 174         }\r
 175 \r
 176         public void next() throws HistoryException {\r
 177                 //if (index>=0) \r
 178                 gotoIndex( index+1 );\r
 179         }\r
 180         \r
 181         public ValueBand getValueBand() {\r
 182                 return valueBand;\r
 183         }\r
 184         \r
 185         public Object getValue(Binding binding) throws HistoryException {\r
 186                 return valueBand.getValue(binding);\r
 187         }\r
 188         \r
 189         public Object getSample() {\r
 190                 return current;\r
 191         }\r
 192         \r
 193         public RecordBinding getSampleBinding() {\r
 194                 return sampleBinding;\r
 195         }\r
 196         \r
 197         public boolean hasValue() {\r
 198                 return index!=-1;\r
 199         }\r
 200         \r
 201         public boolean hasValidValue() throws HistoryException {\r
 202                 return index!=-1 && !valueBand.isNanSample() && !valueBand.isNullValue();\r
 203         }\r
 204         /**\r
 205          * Get the start time. The value is valid if index != -1\r
 206          * @return start time\r
 207          */\r
 208         public double getStartTime() {\r
 209                 return startTime;\r
 210         }\r
 211         \r
 212         /**\r
 213          * Get end time, the value is valid if index != -1\r
 214          * @return end time\r
 215          */\r
 216         public double getEndTime() {\r
 217                 return endTime;\r
 218         }\r
 219         \r
 220         public Double getNextTime() throws HistoryException {\r
 221                 if ( size==0 ) return null;\r
 222                 if ( index==-1 ) return from;\r
 223                 return (Double) nextValueBand.getTime(Bindings.DOUBLE);\r
 224         }\r
 225         \r
 226         public Double getNextTime( double currentTime ) throws HistoryException {\r
 227                 if ( size==0 ) return null;\r
 228                 if ( index==-1 ) return from;\r
 229                 \r
 230                 if ( valueBand.hasEndTime() ) {\r
 231                         Double endTime = (Double) valueBand.getEndTime(Bindings.DOUBLE);\r
 232                         if ( endTime>currentTime ) return endTime;\r
 233                 }\r
 234                 \r
 235                 double nextTime = (Double) nextValueBand.getTime(Bindings.DOUBLE);\r
 236                 return nextTime;\r
 237         }\r
 238         \r
 239         \r
 240         \r
 241         /**\r
 242          * get index of the cursor\r
 243          * @return index or -1\r
 244          */\r
 245         public int getIndex() {\r
 246                 return index;\r
 247         }\r
 248         \r
 249         @Override\r
 250         public String toString() {\r
 251                 Binding valueBinding = valueBand.getValueBinding();\r
 252                 String valueStr;\r
 253                 try {\r
 254                         valueStr = valueBinding.toString( valueBand.getValue() );\r
 255                 } catch (BindingException e) {\r
 256                         valueStr = e.toString();\r
 257                 } catch (HistoryException e) {\r
 258                         valueStr = e.toString();\r
 259                 }\r
 260                 if ( hasValue() ) {\r
 261                         return "i="+index+", time=["+startTime+"-"+endTime+"], value="+valueStr;\r
 262                 } else {\r
 263                         return "<no value>";\r
 264                 }\r
 265         }\r
 266         \r
 267         /**\r
 268          * Get start time of the first sample.\r
 269          * @return time\r
 270          */\r
 271         public double getFirstTime() {\r
 272                 return from;\r
 273         }\r
 274         \r
 275         /**\r
 276          * Get end time of the last sample.\r
 277          * @return time\r
 278          */\r
 279         public double getLastTime() {\r
 280                 return end;\r
 281         }\r
 282         \r
 283         public int size() {\r
 284                 return size;\r
 285         }\r
 286         \r
 287         public boolean isEmpty() {\r
 288                 return size==0;\r
 289         }\r
 290         \r
 291 }\r