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<String[]> _pointList = new ArrayList<String[]>();
  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().trim();
  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                         boolean firstPoint = true;
 101                         for (int p=0; p<numPoints; p++)
 102                         {
 103                                 if (coordArray[p] != null && coordArray[p].trim().length()>3)
 104                                 {
 105                                         String[] pointArray = makeStringArray(coordArray[p], null);
 106                                         if (firstPoint) {pointArray[4] = "1";} // start of segment flag
 107                                         firstPoint = false;
 108                                         _pointList.add(pointArray);
 109                                 }
 110                         }
 111                 }
 112         }
 113
 114
 115         /**
 116          * Construct the String array for the given coordinates and name
 117          * @param inCoordinates coordinate string in Kml format
 118          * @param inName name of waypoint, or null if track point
 119          * @return String array for point
 120          */
 121         private static String[] makeStringArray(String inCoordinates, String inName)
 122         {
 123                 String[] result = new String[5];
 124                 String[] values = inCoordinates.split(",");
 125                 if (values.length == 3) {System.arraycopy(values, 0, result, 0, 3);}
 126                 result[3] = inName;
 127                 return result;
 128         }
 129
 130
 131         /**
 132          * @see tim.prune.load.xml.XmlHandler#getFieldArray()
 133          */
 134         public Field[] getFieldArray()
 135         {
 136                 final Field[] fields = {Field.LONGITUDE, Field.LATITUDE, Field.ALTITUDE, Field.WAYPT_NAME, Field.NEW_SEGMENT};
 137                 return fields;
 138         }
 139
 140
 141         /**
 142          * Return the parsed information as a 2d array
 143          * @see tim.prune.load.xml.XmlHandler#getDataArray()
 144          */
 145         public String[][] getDataArray()
 146         {
 147                 int numPoints = _pointList.size();
 148                 // construct data array
 149                 String[][] result = new String[numPoints][];
 150                 for (int i=0; i<numPoints; i++)
 151                 {
 152                         result[i] = _pointList.get(i);
 153                 }
 154                 return result;
 155         }
 156
 157 }