tim/prune/data/sort/WaypointComparer.java

   1 package tim.prune.data.sort;
   2
   3 import java.util.Comparator;
   4
   5 import tim.prune.data.DataPoint;
   6
   7
   8 /**
   9  * Class for comparing waypoints to sort them by name or timestamp
  10  */
  11 public class WaypointComparer implements Comparator<DataPoint>
  12 {
  13         /** Sort mode */
  14         private SortMode _sortMode;
  15
  16
  17         /**
  18          * Constructor
  19          * @param inMode sort mode
  20          */
  21         public WaypointComparer(SortMode inMode)
  22         {
  23                 _sortMode = inMode;
  24         }
  25
  26         /**
  27          * Main compare method
  28          */
  29         public int compare(DataPoint inP1, DataPoint inP2)
  30         {
  31                 if (inP2 == null || !inP2.isWaypoint()) return -1; // all nulls at end
  32                 if (inP1 == null || !inP1.isWaypoint()) return 1;
  33
  34                 // Sort by time, if requested
  35                 int result = 0;
  36                 if (_sortMode == SortMode.SORTBY_TIME) {
  37                         result = compareTimes(inP1, inP2);
  38                 }
  39                 // check names if names requested or if times didn't work
  40                 if (result == 0) {
  41                         result = inP1.getWaypointName().compareTo(inP2.getWaypointName());
  42                 }
  43                 // names and times equal, try longitude
  44                 if (result == 0) {
  45                         result = inP1.getLongitude().getDouble() > inP2.getLongitude().getDouble() ? 1 : -1;
  46                 }
  47                 // and latitude
  48                 if (result == 0) {
  49                         result = inP1.getLatitude().getDouble() > inP2.getLatitude().getDouble() ? 1 : -1;
  50                 }
  51                 return result;
  52         }
  53
  54         /**
  55          * Compare the timestamps of the two waypoints
  56          * @param inP1 first point
  57          * @param inP2 second point
  58          * @return compare value (-1,0,1)
  59          */
  60         private int compareTimes(DataPoint inP1, DataPoint inP2)
  61         {
  62                 // Points might not have timestamps
  63                 if (inP1.hasTimestamp() && !inP2.hasTimestamp()) return 1;
  64                 if (!inP1.hasTimestamp() && inP2.hasTimestamp()) return -1;
  65                 if (inP1.hasTimestamp() && inP2.hasTimestamp())
  66                 {
  67                         // Compare the timestamps
  68                         long secDiff = inP1.getTimestamp().getMillisecondsSince(inP2.getTimestamp());
  69                         return (secDiff<0?-1:(secDiff==0?0:1));
  70                 }
  71                 // neither has a timestamp
  72                 return 0;
  73         }
  74 }