src/tim/prune/load/xml/GpxHandler.java

   1 package tim.prune.load.xml;
   2
   3 import java.util.ArrayList;
   4
   5 import org.xml.sax.Attributes;
   6 import org.xml.sax.SAXException;
   7
   8 import tim.prune.data.Field;
   9 import tim.prune.load.TrackNameList;
  10
  11
  12 /**
  13  * Class for handling specifics of parsing Gpx files
  14  */
  15 public class GpxHandler extends XmlHandler
  16 {
  17         private boolean _insidePoint = false;
  18         private boolean _insideWaypoint = false;
  19         private boolean _startSegment = true;
  20         private boolean _isTrackPoint = false;
  21         private int _trackNum = -1;
  22         private GpxTag _fileTitle = new GpxTag();
  23         private GpxTag _pointName = new GpxTag(), _trackName = new GpxTag();
  24         private String _latitude = null, _longitude = null;
  25         private GpxTag _elevation = new GpxTag(), _time = new GpxTag();
  26         private GpxTag _type = new GpxTag(), _description = new GpxTag();
  27         private GpxTag _link = new GpxTag(), _comment = new GpxTag();
  28         private GpxTag _currentTag = null;
  29         private ArrayList<String[]> _pointList = new ArrayList<String[]>();
  30         private ArrayList<String> _linkList = new ArrayList<String>();
  31         private TrackNameList _trackNameList = new TrackNameList();
  32
  33
  34         /**
  35          * Receive the start of a tag
  36          * @see org.xml.sax.ContentHandler#startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)
  37          */
  38         public void startElement(String uri, String localName, String qName,
  39                 Attributes attributes) throws SAXException
  40         {
  41                 // Read the parameters for waypoints and track points
  42                 String tag = qName.toLowerCase();
  43                 if (tag.equals("wpt") || tag.equals("trkpt") || tag.equals("rtept"))
  44                 {
  45                         _insidePoint = true;
  46                         _insideWaypoint = tag.equals("wpt");
  47                         _isTrackPoint = tag.equals("trkpt");
  48                         final int numAttributes = attributes.getLength();
  49                         for (int i=0; i<numAttributes; i++)
  50                         {
  51                                 String att = attributes.getQName(i).toLowerCase();
  52                                 if (att.equals("lat")) {_latitude = attributes.getValue(i);}
  53                                 else if (att.equals("lon")) {_longitude = attributes.getValue(i);}
  54                         }
  55                         _elevation.setValue(null);
  56                         _pointName.setValue(null);
  57                         _time.setValue(null);
  58                         _type.setValue(null);
  59                         _link.setValue(null);
  60                         _description.setValue(null);
  61                         _comment.setValue(null);
  62                 }
  63                 else if (tag.equals("ele")) {
  64                         _currentTag = _elevation;
  65                 }
  66                 else if (tag.equals("name"))
  67                 {
  68                         if (_insidePoint) {
  69                                 _currentTag = _pointName;
  70                         }
  71                         else if (_trackNum < 0)
  72                         {
  73                                 _currentTag = _fileTitle;
  74                         }
  75                         else {
  76                                 _currentTag = _trackName;
  77                         }
  78                 }
  79                 else if (tag.equals("time")) {
  80                         _currentTag = _time;
  81                 }
  82                 else if (tag.equals("type")) {
  83                         _currentTag = _type;
  84                 }
  85                 else if (tag.equals("description") || tag.equals("desc")) {
  86                         _currentTag = _description;
  87                 }
  88                 else if (tag.equals("cmt")) {
  89                         _currentTag = _comment;
  90                 }
  91                 else if (tag.equals("link")) {
  92                         _link.setValue(attributes.getValue("href"));
  93                 }
  94                 else if (tag.equals("trkseg")) {
  95                         _startSegment = true;
  96                 }
  97                 else if (tag.equals("trk"))
  98                 {
  99                         _trackNum++;
 100                         _trackName.setValue(null);
 101                 }
 102                 super.startElement(uri, localName, qName, attributes);
 103         }
 104
 105
 106         /**
 107          * Process end tag
 108          * @see org.xml.sax.ContentHandler#endElement(java.lang.String, java.lang.String, java.lang.String)
 109          */
 110         public void endElement(String uri, String localName, String qName)
 111                 throws SAXException
 112         {
 113                 String tag = qName.toLowerCase();
 114                 if (tag.equals("wpt") || tag.equals("trkpt") || tag.equals("rtept"))
 115                 {
 116                         processPoint();
 117                         _insidePoint = false;
 118                 }
 119                 else {
 120                         _currentTag = null;
 121                 }
 122                 super.endElement(uri, localName, qName);
 123         }
 124
 125
 126         /**
 127          * Process character text (inside tags or between them)
 128          * @see org.xml.sax.ContentHandler#characters(char[], int, int)
 129          */
 130         public void characters(char[] ch, int start, int length)
 131                 throws SAXException
 132         {
 133                 String value = new String(ch, start, length);
 134                 if (_currentTag != null) {
 135                         _currentTag.setValue(checkCharacters(_currentTag.getValue(), value));
 136                 }
 137                 super.characters(ch, start, length);
 138         }
 139
 140
 141         /**
 142          * Check to concatenate partially-received values, if necessary
 143          * @param inVariable variable containing characters received until now
 144          * @param inValue new value received
 145          * @return concatenation
 146          */
 147         private static String checkCharacters(String inVariable, String inValue)
 148         {
 149                 if (inVariable == null) {return inValue;}
 150                 return inVariable + inValue;
 151         }
 152
 153
 154         /**
 155          * Process a point, either a waypoint or track point
 156          */
 157         private void processPoint()
 158         {
 159                 // Put the values into a String array matching the order in getFieldArray()
 160                 String[] values = new String[9];
 161                 values[0] = _latitude;
 162                 values[1] = _longitude;
 163                 values[2] = _elevation.getValue();
 164                 if (_insideWaypoint) {values[3] = _pointName.getValue();}
 165                 values[4] = _time.getValue();
 166                 if (_startSegment && !_insideWaypoint)
 167                 {
 168                         values[5] = "1";
 169                         _startSegment = false;
 170                 }
 171                 values[6] = _type.getValue();
 172                 values[7] = _description.getValue();
 173                 values[8] = _comment.getValue();
 174                 _pointList.add(values);
 175                 _trackNameList.addPoint(_trackNum, _trackName.getValue(), _isTrackPoint);
 176                 _linkList.add(_link.getValue());
 177         }
 178
 179
 180         /**
 181          * @see tim.prune.load.xml.XmlHandler#getFieldArray()
 182          */
 183         public Field[] getFieldArray()
 184         {
 185                 final Field[] fields = {Field.LATITUDE, Field.LONGITUDE, Field.ALTITUDE,
 186                         Field.WAYPT_NAME, Field.TIMESTAMP, Field.NEW_SEGMENT,
 187                         Field.WAYPT_TYPE, Field.DESCRIPTION, Field.COMMENT};
 188                 return fields;
 189         }
 190
 191
 192         /**
 193          * Return the parsed information as a 2d array
 194          * @see tim.prune.load.xml.XmlHandler#getDataArray()
 195          */
 196         public String[][] getDataArray()
 197         {
 198                 int numPoints = _pointList.size();
 199                 // construct data array
 200                 String[][] result = new String[numPoints][];
 201                 for (int i=0; i<numPoints; i++)
 202                 {
 203                         result[i] = _pointList.get(i);
 204                 }
 205                 return result;
 206         }
 207
 208         /**
 209          * @return array of links, or null if none
 210          */
 211         public String[] getLinkArray()
 212         {
 213                 int numPoints = _linkList.size();
 214                 boolean hasLink = false;
 215                 String[] result = new String[numPoints];
 216                 for (int i=0; i<numPoints; i++)
 217                 {
 218                         result[i] = _linkList.get(i);
 219                         if (result[i] != null) {hasLink = true;}
 220                 }
 221                 if (!hasLink) {result = null;}
 222                 return result;
 223         }
 224
 225         /**
 226          * @return track name list
 227          */
 228         public TrackNameList getTrackNameList() {
 229                 return _trackNameList;
 230         }
 231
 232         /**
 233          * @return file title
 234          */
 235         public String getFileTitle() {
 236                 return _fileTitle.getValue();
 237         }
 238 }