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.search.SearchResult;
  10
  11 /**
  12  * XML handler for dealing with XML returned from the geonames api,
  13  * both from the search by name and search by location
  14  */
  15 public class GetWikipediaXmlHandler extends DefaultHandler
  16 {
  17         private String _value = null;
  18         private ArrayList<SearchResult> _trackList = null;
  19         private SearchResult _track = 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<SearchResult>();
  31                 }
  32                 else if (inTagName.equals("entry")) {
  33                         _track = new SearchResult();
  34                 }
  35                 else if (inTagName.equals("status")) {
  36                         _errorMessage = inAttributes.getValue("message");
  37                 }
  38                 else _value = null;
  39                 super.startElement(inUri, inLocalName, inTagName, inAttributes);
  40         }
  41
  42         /**
  43          * React to the end of an XML tag
  44          */
  45         public void endElement(String inUri, String inLocalName, String inTagName)
  46         throws SAXException
  47         {
  48                 if (inTagName.equals("entry")) {
  49                         // end of the entry
  50                         _trackList.add(_track);
  51                 }
  52                 else if (inTagName.equals("title")) {
  53                         _track.setTrackName(_value);
  54                 }
  55                 else if (inTagName.equals("summary")) {
  56                         _track.setDescription(_value);
  57                 }
  58                 else if (inTagName.equals("lat")) {
  59                         _track.setLatitude(_value);
  60                 }
  61                 else if (inTagName.equals("lng")) {
  62                         _track.setLongitude(_value);
  63                 }
  64                 else if (inTagName.equals("distance")) {
  65                         try {
  66                                 _track.setLength(Double.parseDouble(_value) * 1000.0); // convert from km to m
  67                         }
  68                         catch (NumberFormatException nfe) {}
  69                 }
  70                 else if (inTagName.equals("wikipediaUrl")) {
  71                         _track.setWebUrl(_value.replaceFirst("http://", "https://"));
  72                 }
  73                 super.endElement(inUri, inLocalName, inTagName);
  74         }
  75
  76         /**
  77          * React to characters received inside tags
  78          */
  79         public void characters(char[] inCh, int inStart, int inLength)
  80         throws SAXException
  81         {
  82                 String value = new String(inCh, inStart, inLength);
  83                 _value = (_value==null?value:_value+value);
  84                 super.characters(inCh, inStart, inLength);
  85         }
  86
  87         /**
  88          * @return the list of tracks
  89          */
  90         public ArrayList<SearchResult> getTrackList()
  91         {
  92                 return _trackList;
  93         }
  94
  95         /**
  96          * @return error message, if any
  97          */
  98         public String getErrorMessage() {
  99                 return _errorMessage;
 100         }
 101 }