tim/prune/load/xml/KmlHandler.java

   1 package tim.prune.load.xml;
   2
   3 import java.util.ArrayList;
   4 import org.xml.sax.Attributes;
   5 import org.xml.sax.SAXException;
   6
   7 import tim.prune.data.Field;
   8
   9
  10 /**
  11  * Class for handling specifics of parsing Kml files
  12  */
  13 public class KmlHandler extends XmlHandler
  14 {
  15         private boolean _insidePlacemark = false;
  16         private boolean _insideName = false;
  17         private boolean _insideCoordinates = false;
  18         private String _name = null;
  19         private StringBuffer _coordinates = null;
  20         private ArrayList _pointList = new ArrayList();
  21
  22
  23         /**
  24          * Receive the start of a tag
  25          * @see org.xml.sax.ContentHandler#startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)
  26          */
  27         public void startElement(String uri, String localName, String qName,
  28                         Attributes attributes) throws SAXException
  29         {
  30                 String tagName = localName;
  31                 if (tagName == null || tagName.equals("")) {tagName = qName;}
  32                 if (tagName.equalsIgnoreCase("Placemark")) _insidePlacemark = true;
  33                 else if (tagName.equalsIgnoreCase("coordinates")) {_insideCoordinates = true; _coordinates = null;}
  34                 else if (tagName.equalsIgnoreCase("name")) {_insideName = true; _name = null;}
  35                 super.startElement(uri, localName, qName, attributes);
  36         }
  37
  38
  39         /**
  40          * Process end tag
  41          * @see org.xml.sax.ContentHandler#endElement(java.lang.String, java.lang.String, java.lang.String)
  42          */
  43         public void endElement(String uri, String localName, String qName)
  44         throws SAXException
  45         {
  46                 String tagName = localName;
  47                 if (tagName == null || tagName.equals("")) {tagName = qName;}
  48                 if (tagName.equalsIgnoreCase("Placemark"))
  49                 {
  50                         processPlacemark();
  51                         _insidePlacemark = false;
  52                 }
  53                 else if (tagName.equalsIgnoreCase("coordinates")) _insideCoordinates = false;
  54                 else if (tagName.equalsIgnoreCase("name")) _insideName = false;
  55                 super.endElement(uri, localName, qName);
  56         }
  57
  58
  59         /**
  60          * Process character text (inside tags or between them)
  61          * @see org.xml.sax.ContentHandler#characters(char[], int, int)
  62          */
  63         public void characters(char[] ch, int start, int length)
  64                         throws SAXException
  65         {
  66                 if (_insidePlacemark && (_insideName || _insideCoordinates))
  67                 {
  68                         String value = new String(ch, start, length);
  69                         if (_insideName) {_name = value;}
  70                         else if (_insideCoordinates)
  71                         {
  72                                 if (_coordinates == null)
  73                                 {
  74                                         _coordinates = new StringBuffer();
  75                                 }
  76                                 _coordinates.append(value);
  77                         }
  78                 }
  79                 super.characters(ch, start, length);
  80         }
  81
  82
  83         /**
  84          * Process a placemark entry, either a single waypoint or a whole track
  85          */
  86         private void processPlacemark()
  87         {
  88                 if (_coordinates == null) return;
  89                 String allCoords = _coordinates.toString();
  90                 String[] coordArray = allCoords.split("[ \n]");
  91                 int numPoints = coordArray.length;
  92                 if (numPoints == 1)
  93                 {
  94                         // Add single waypoint to list
  95                         _pointList.add(makeStringArray(allCoords, _name));
  96                 }
  97                 else if (numPoints > 1)
  98                 {
  99                         // Add each of the unnamed track points to list
 100                         for (int p=0; p<numPoints; p++)
 101                         {
 102                                 _pointList.add(makeStringArray(coordArray[p], null));
 103                         }
 104                 }
 105         }
 106
 107
 108         /**
 109          * Construct the String array for the given coordinates and name
 110          * @param inCoordinates coordinate string in Kml format
 111          * @param inName name of waypoint, or null if track point
 112          * @return String array for point
 113          */
 114         private static String[] makeStringArray(String inCoordinates, String inName)
 115         {
 116                 String[] result = new String[4];
 117                 String[] values = inCoordinates.split(",");
 118                 if (values.length == 3) {System.arraycopy(values, 0, result, 0, 3);}
 119                 result[3] = inName;
 120                 return result;
 121         }
 122
 123
 124         /**
 125          * @see tim.prune.load.xml.XmlHandler#getFieldArray()
 126          */
 127         public Field[] getFieldArray()
 128         {
 129                 final Field[] fields = {Field.LONGITUDE, Field.LATITUDE, Field.ALTITUDE, Field.WAYPT_NAME};
 130                 return fields;
 131         }
 132
 133
 134         /**
 135          * Return the parsed information as a 2d array
 136          * @see tim.prune.load.xml.XmlHandler#getDataArray()
 137          */
 138         public String[][] getDataArray()
 139         {
 140                 int numPoints = _pointList.size();
 141                 // construct data array
 142                 String[][] result = new String[numPoints][];
 143                 for (int i=0; i<numPoints; i++)
 144                 {
 145                         result[i] = (String[]) _pointList.get(i);
 146                 }
 147                 return result;
 148         }
 149
 150 }