tim/prune/undo/UndoReverseSection.java

   1 package tim.prune.undo;
   2
   3 import tim.prune.I18nManager;
   4 import tim.prune.data.DataPoint;
   5 import tim.prune.data.Track;
   6 import tim.prune.data.TrackInfo;
   7
   8 /**
   9  * Undo reversal of track section
  10  */
  11 public class UndoReverseSection implements UndoOperation
  12 {
  13         /** Start and end indices of section */
  14         private int _startIndex, _endIndex;
  15         /** First and last track point in section and next track point after */
  16         private DataPoint _firstTrackPoint, _lastTrackPoint, _nextTrackPoint;
  17         /** Segment flags for these points */
  18         private boolean _firstSegmentFlag, _lastSegmentFlag, _nextSegmentFlag;
  19
  20
  21         /**
  22          * Constructor
  23          * @param inTrack track object for copying segment flags
  24          * @param inStart start index of section
  25          * @param inEnd end index of section
  26          */
  27         public UndoReverseSection(Track inTrack, int inStart, int inEnd)
  28         {
  29                 _startIndex = inStart;
  30                 _endIndex = inEnd;
  31                 // Look for first track point in section to be reversed, store flag
  32                 _firstTrackPoint = inTrack.getNextTrackPoint(inStart);
  33                 if (_firstTrackPoint != null) {
  34                         _firstSegmentFlag = _firstTrackPoint.getSegmentStart();
  35                 }
  36                 // Look for last track point in section to be reversed, store flag
  37                 _lastTrackPoint = inTrack.getPreviousTrackPoint(inEnd);
  38                 if (_lastTrackPoint != null) {
  39                         _lastSegmentFlag = _lastTrackPoint.getSegmentStart();
  40                 }
  41                 // Look for following track point, store flag
  42                 _nextTrackPoint = inTrack.getNextTrackPoint(inEnd + 1);
  43                 if (_nextTrackPoint != null) {
  44                         _nextSegmentFlag = _nextTrackPoint.getSegmentStart();
  45                 }
  46         }
  47
  48
  49         /**
  50          * @return description of operation
  51          */
  52         public String getDescription()
  53         {
  54                 return I18nManager.getText("undo.reverse");
  55         }
  56
  57
  58         /**
  59          * Perform the undo operation on the given Track
  60          * @param inTrackInfo TrackInfo object on which to perform the operation
  61          */
  62         public void performUndo(TrackInfo inTrackInfo) throws UndoException
  63         {
  64                 if (!inTrackInfo.getTrack().reverseRange(_startIndex, _endIndex))
  65                 {
  66                         throw new UndoException(getDescription());
  67                 }
  68                 // Restore segment start flags
  69                 if (_firstTrackPoint != null) {
  70                         _firstTrackPoint.setSegmentStart(_firstSegmentFlag);
  71                 }
  72                 if (_lastTrackPoint != null) {
  73                         _lastTrackPoint.setSegmentStart(_lastSegmentFlag);
  74                 }
  75                 if (_nextTrackPoint != null) {
  76                         _nextTrackPoint.setSegmentStart(_nextSegmentFlag);
  77                 }
  78         }
  79 }