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 _insideName = false;
  20         private boolean _insideElevation = false;
  21         private boolean _insideTime = false;
  22         private boolean _insideType = false;
  23         private boolean _startSegment = true;
  24         private boolean _isTrackPoint = false;
  25         private int _trackNum = -1;
  26         private String _trackName = null;
  27         private String _name = null, _latitude = null, _longitude = null;
  28         private String _elevation = null;
  29         private String _time = null;
  30         private String _type = null;
  31         private ArrayList<String[]> _pointList = new ArrayList<String[]>();
  32         private TrackNameList _trackNameList = new TrackNameList();
  33
  34
  35         /**
  36          * Receive the start of a tag
  37          * @see org.xml.sax.ContentHandler#startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)
  38          */
  39         public void startElement(String uri, String localName, String qName,
  40                 Attributes attributes) throws SAXException
  41         {
  42                 // Read the parameters for waypoints and track points
  43                 if (qName.equalsIgnoreCase("wpt") || qName.equalsIgnoreCase("trkpt") || qName.equalsIgnoreCase("rtept"))
  44                 {
  45                         _insidePoint = true;
  46                         _insideWaypoint = qName.equalsIgnoreCase("wpt");
  47                         _isTrackPoint = qName.equalsIgnoreCase("trkpt");
  48                         int numAttributes = attributes.getLength();
  49                         for (int i=0; i<numAttributes; i++)
  50                         {
  51                                 String att = attributes.getQName(i);
  52                                 if (att.equals("lat")) {_latitude = attributes.getValue(i);}
  53                                 else if (att.equals("lon")) {_longitude = attributes.getValue(i);}
  54                         }
  55                         _elevation = null;
  56                         _name = null;
  57                         _time = null;
  58                         _type = null;
  59                 }
  60                 else if (qName.equalsIgnoreCase("ele"))
  61                 {
  62                         _insideElevation = true;
  63                 }
  64                 else if (qName.equalsIgnoreCase("name"))
  65                 {
  66                         _name = null;
  67                         _insideName = true;
  68                 }
  69                 else if (qName.equalsIgnoreCase("time"))
  70                 {
  71                         _insideTime = true;
  72                 }
  73                 else if (qName.equalsIgnoreCase("type"))
  74                 {
  75                         _insideType = true;
  76                 }
  77                 else if (qName.equalsIgnoreCase("trkseg"))
  78                 {
  79                         _startSegment = true;
  80                 }
  81                 else if (qName.equalsIgnoreCase("trk"))
  82                 {
  83                         _trackNum++;
  84                         _trackName = null;
  85                 }
  86                 super.startElement(uri, localName, qName, attributes);
  87         }
  88
  89
  90         /**
  91          * Process end tag
  92          * @see org.xml.sax.ContentHandler#endElement(java.lang.String, java.lang.String, java.lang.String)
  93          */
  94         public void endElement(String uri, String localName, String qName)
  95                 throws SAXException
  96         {
  97                 if (qName.equalsIgnoreCase("wpt") || qName.equalsIgnoreCase("trkpt") || qName.equalsIgnoreCase("rtept"))
  98                 {
  99                         processPoint();
 100                         _insidePoint = false;
 101                 }
 102                 else if (qName.equalsIgnoreCase("ele"))
 103                 {
 104                         _insideElevation = false;
 105                 }
 106                 else if (qName.equalsIgnoreCase("name"))
 107                 {
 108                         _insideName = false;
 109                 }
 110                 else if (qName.equalsIgnoreCase("time"))
 111                 {
 112                         _insideTime = false;
 113                 }
 114                 else if (qName.equalsIgnoreCase("type"))
 115                 {
 116                         _insideType = false;
 117                 }
 118                 super.endElement(uri, localName, qName);
 119         }
 120
 121
 122         /**
 123          * Process character text (inside tags or between them)
 124          * @see org.xml.sax.ContentHandler#characters(char[], int, int)
 125          */
 126         public void characters(char[] ch, int start, int length)
 127                 throws SAXException
 128         {
 129                 String value = new String(ch, start, length);
 130                 if (_insideName && _insideWaypoint) {_name = checkCharacters(_name, value);}
 131                 if (_insideName && !_insidePoint) {_trackName = checkCharacters(_trackName, value);}
 132                 else if (_insideElevation) {_elevation = checkCharacters(_elevation, value);}
 133                 else if (_insideTime) {_time = checkCharacters(_time, value);}
 134                 else if (_insideType) {_type = checkCharacters(_type, value);}
 135                 super.characters(ch, start, length);
 136         }
 137
 138
 139         /**
 140          * Check to concatenate partially-received values, if necessary
 141          * @param inVariable variable containing characters received until now
 142          * @param inValue new value received
 143          * @return concatenation
 144          */
 145         private static String checkCharacters(String inVariable, String inValue)
 146         {
 147                 if (inVariable == null) {return inValue;}
 148                 return inVariable + inValue;
 149         }
 150
 151
 152         /**
 153          * Process a point, either a waypoint or track point
 154          */
 155         private void processPoint()
 156         {
 157                 // Put the values into a String array matching the order in getFieldArray()
 158                 String[] values = new String[7];
 159                 values[0] = _latitude; values[1] = _longitude;
 160                 values[2] = _elevation; values[3] = _name;
 161                 values[4] = _time;
 162                 if (_startSegment && !_insideWaypoint) {
 163                         values[5] = "1";
 164                         _startSegment = false;
 165                 }
 166                 values[6] = _type;
 167                 _pointList.add(values);
 168                 _trackNameList.addPoint(_trackNum, _trackName, _isTrackPoint);
 169         }
 170
 171
 172         /**
 173          * @see tim.prune.load.xml.XmlHandler#getFieldArray()
 174          */
 175         public Field[] getFieldArray()
 176         {
 177                 final Field[] fields = {Field.LATITUDE, Field.LONGITUDE, Field.ALTITUDE,
 178                         Field.WAYPT_NAME, Field.TIMESTAMP, Field.NEW_SEGMENT, Field.WAYPT_TYPE};
 179                 return fields;
 180         }
 181
 182
 183         /**
 184          * Return the parsed information as a 2d array
 185          * @see tim.prune.load.xml.XmlHandler#getDataArray()
 186          */
 187         public String[][] getDataArray()
 188         {
 189                 int numPoints = _pointList.size();
 190                 // construct data array
 191                 String[][] result = new String[numPoints][];
 192                 for (int i=0; i<numPoints; i++)
 193                 {
 194                         result[i] = _pointList.get(i);
 195                 }
 196                 return result;
 197         }
 198
 199
 200         /**
 201          * @return track name list
 202          */
 203         public TrackNameList getTrackNameList() {
 204                 return _trackNameList;
 205         }
 206 }