bundles/org.simantics.history/src/org/simantics/history/HistorySamplerItem2.java

   1 package org.simantics.history;
   2
   3 import java.util.Arrays;
   4
   5 import org.simantics.databoard.accessor.StreamAccessor;
   6 import org.simantics.databoard.accessor.error.AccessorException;
   7 import org.simantics.history.util.StreamIterator;
   8
   9 public class HistorySamplerItem2 implements Comparable<HistorySamplerItem2> {
  10
  11         public static class LevelItem implements Comparable<LevelItem> {
  12                 public final String id;
  13                 public final double samplingInterval;
  14
  15                 public LevelItem(String id, double samplingInterval) {
  16                         this.id = id;
  17                         this.samplingInterval = samplingInterval;
  18                 }
  19
  20                 @Override
  21                 public int compareTo(LevelItem o) {
  22                         int i = id.compareTo(o.id);
  23                         return i != 0 ? i : Double.compare(samplingInterval, o.samplingInterval);
  24                 }
  25         }
  26
  27         Collector collector;
  28         HistoryManager history;         // History source for this item
  29         LevelItem[] items;
  30
  31         // State data
  32         StreamAccessor accessor;                        // Stream accessor
  33         public StreamIterator iter;
  34         public int chartDataId;
  35
  36         public HistorySamplerItem2(Collector collector, HistoryManager history, LevelItem[] items, int identityHashCode) {
  37                 if (items.length == 0)
  38                         throw new IllegalArgumentException("Must have at least one existing history item to sample, zero provided");
  39                 this.collector = collector;
  40                 this.history = history;
  41                 this.items = items;
  42                 this.chartDataId = identityHashCode;
  43         }
  44
  45         public void flush() throws HistoryException {
  46                 if (collector != null)
  47                         collector.flush();
  48         }
  49
  50         public void open() throws HistoryException {
  51                 accessor = history.openStream(items[0].id, "r");
  52                 iter = new StreamIterator( accessor );
  53         }
  54
  55         public void open(double pixelsPerSecond) throws HistoryException {
  56                 LevelItem f = getFormat(pixelsPerSecond);
  57                 accessor = history.openStream(f.id, "r");
  58                 iter = new StreamIterator( accessor );
  59         }
  60
  61         public void close() {
  62                 if (accessor!=null) {
  63                         try {
  64                                 accessor.close();
  65                         } catch (AccessorException e) {
  66                         }
  67                 }
  68                 accessor = null;
  69                 iter = null;
  70         }
  71
  72         @Override
  73         public int compareTo(HistorySamplerItem2 o) {
  74                 int m = Math.min(items.length, o.items.length);
  75                 for (int j = 0; j < m; ++j) {
  76                         int i = items[j].compareTo(o.items[j]);
  77                         if (i != 0)
  78                                 return i;
  79                 }
  80                 return 0;
  81         }
  82
  83         @Override
  84         public int hashCode() {
  85                 int code = 0x2304;
  86                 code = 13*code + Arrays.hashCode(items);
  87                 code = 13*code + history.hashCode();
  88                 return code;
  89         }
  90
  91         @Override
  92         public boolean equals(Object obj) {
  93                 if ( obj == null ) return false;
  94                 if ( obj instanceof HistorySamplerItem2 == false ) return false;
  95                 HistorySamplerItem2 other = (HistorySamplerItem2) obj;
  96                 if ( !other.history.equals(history) ) return false;
  97                 if ( !Arrays.equals(other.items, items) ) return false;
  98                 return true;
  99         }
 100
 101         private LevelItem getFormat(double secondsPerPixel) throws HistoryException {
 102                 LevelItem result = null;
 103                 for (LevelItem format : items) {
 104                         double interval = format.samplingInterval;
 105                         if (Double.isNaN( interval ) || interval <= secondsPerPixel) {
 106                                 result = format;
 107                         } else {
 108                                 break;
 109                         }
 110                 }
 111                 return result;
 112         }
 113
 114 }