gov/nasa/worldwind/TrackPointIteratorImpl.java

   1 /*
   2 Copyright (C) 2001, 2006 United States Government
   3 as represented by the Administrator of the
   4 National Aeronautics and Space Administration.
   5 All Rights Reserved.
   6 */
   7 package gov.nasa.worldwind;
   8
   9 import java.util.*;
  10
  11 /**
  12  * @author tag
  13  * @version $Id$
  14  */
  15 public class TrackPointIteratorImpl implements TrackPointIterator
  16 {
  17     private java.util.List<Track> tracksList;
  18     private java.util.Iterator<Track> tracks;
  19     private java.util.Iterator<TrackSegment> segments;
  20     private java.util.Iterator<TrackPoint> positions;
  21
  22     public TrackPointIteratorImpl(java.util.List<Track> tracksList)
  23     {
  24         this.tracksList = tracksList;
  25         this.reset();
  26     }
  27
  28     public TrackPointIteratorImpl reset()
  29     {
  30         if (this.tracksList == null)
  31         {
  32             String msg = WorldWind.retrieveErrMsg("nullValue.TracksIsNull");
  33             WorldWind.logger().log(java.util.logging.Level.FINE, msg);
  34             throw new IllegalArgumentException(msg);
  35         }
  36
  37         this.tracks = this.tracksList.iterator();
  38         this.segments = null;
  39         this.positions = null;
  40         this.loadNextPositions();
  41
  42         return this;
  43     }
  44
  45     public boolean hasNext()
  46     {
  47         if (this.positions != null && this.positions.hasNext())
  48             return true;
  49
  50         this.loadNextPositions();
  51
  52         return (this.positions != null && this.positions.hasNext());
  53     }
  54
  55     private void loadNextPositions()
  56     {
  57         if (this.segments != null && this.segments.hasNext())
  58         {
  59             TrackSegment segment = this.segments.next();
  60             this.positions = segment.getPoints().iterator();
  61             return;
  62         }
  63
  64         if (this.tracks.hasNext())
  65         {
  66             Track track = this.tracks.next();
  67             this.segments = track.getSegments().iterator();
  68             this.loadNextPositions();
  69         }
  70     }
  71
  72     public TrackPoint next()
  73     {
  74         if (!this.hasNext())
  75         {
  76             String msg = WorldWind.retrieveErrMsg("iterator.NoMoreTrackPoints");
  77             WorldWind.logger().log(java.util.logging.Level.FINE, msg);
  78             throw new NoSuchElementException(msg);
  79         }
  80
  81         return this.positions.next();
  82     }
  83
  84     public void remove()
  85     {
  86         String msg = WorldWind.retrieveErrMsg("iterator.RemoveNotSupported");
  87         WorldWind.logger().log(java.util.logging.Level.FINE, msg);
  88         throw new UnsupportedOperationException(msg);
  89     }
  90
  91     public int getNumPoints()
  92     {
  93         int numPoints;
  94         for (numPoints = 0; this.hasNext(); this.next())
  95             ++numPoints;
  96
  97         return numPoints;
  98     }
  99 }