tim/prune/function/GetWikipediaXmlHandler.java

   1 package tim.prune.function;
   2
   3 import java.util.ArrayList;
   4
   5 import org.xml.sax.Attributes;
   6 import org.xml.sax.SAXException;
   7 import org.xml.sax.helpers.DefaultHandler;
   8
   9 import tim.prune.function.gpsies.GpsiesTrack;
  10
  11 /**
  12  * XML handler for dealing with XML returned from the geonames api
  13  */
  14 public class GetWikipediaXmlHandler extends DefaultHandler
  15 {
  16         private String _value = null;
  17         private ArrayList<GpsiesTrack> _trackList = null;
  18         private GpsiesTrack _track = null;
  19         private String _lat = null, _lon = null;
  20         private String _errorMessage = null;
  21
  22
  23         /**
  24          * React to the start of an XML tag
  25          */
  26         public void startElement(String inUri, String inLocalName, String inTagName,
  27                 Attributes inAttributes) throws SAXException
  28         {
  29                 if (inTagName.equals("geonames")) {
  30                         _trackList = new ArrayList<GpsiesTrack>();
  31                 }
  32                 else if (inTagName.equals("entry")) {
  33                         _track = new GpsiesTrack();
  34                         _lat = null;
  35                         _lon = null;
  36                 }
  37                 else if (inTagName.equals("status")) {
  38                         _errorMessage = inAttributes.getValue("message");
  39                 }
  40                 else _value = null;
  41                 super.startElement(inUri, inLocalName, inTagName, inAttributes);
  42         }
  43
  44         /**
  45          * React to the end of an XML tag
  46          */
  47         public void endElement(String inUri, String inLocalName, String inTagName)
  48         throws SAXException
  49         {
  50                 if (inTagName.equals("entry")) {
  51                         // end of the entry
  52                         _track.setDownloadLink(_lat + "," + _lon);
  53                         _trackList.add(_track);
  54                 }
  55                 else if (inTagName.equals("title")) {
  56                         _track.setTrackName(_value);
  57                 }
  58                 else if (inTagName.equals("summary")) {
  59                         _track.setDescription(_value);
  60                 }
  61                 else if (inTagName.equals("lat")) {
  62                         _lat = _value;
  63                 }
  64                 else if (inTagName.equals("lng")) {
  65                         _lon = _value;
  66                 }
  67                 else if (inTagName.equals("distance")) {
  68                         try {
  69                                 _track.setLength(Double.parseDouble(_value) * 1000.0); // convert from km to m
  70                         }
  71                         catch (NumberFormatException nfe) {}
  72                 }
  73                 else if (inTagName.equals("wikipediaUrl")) {
  74                         _track.setWebUrl(_value.replaceFirst("http://", "https://"));
  75                 }
  76                 super.endElement(inUri, inLocalName, inTagName);
  77         }
  78
  79         /**
  80          * React to characters received inside tags
  81          */
  82         public void characters(char[] inCh, int inStart, int inLength)
  83         throws SAXException
  84         {
  85                 String value = new String(inCh, inStart, inLength);
  86                 _value = (_value==null?value:_value+value);
  87                 super.characters(inCh, inStart, inLength);
  88         }
  89
  90         /**
  91          * @return the list of tracks
  92          */
  93         public ArrayList<GpsiesTrack> getTrackList()
  94         {
  95                 return _trackList;
  96         }
  97
  98         /**
  99          * @return error message, if any
 100          */
 101         public String getErrorMessage() {
 102                 return _errorMessage;
 103         }
 104 }