tim/prune/function/GetWikipediaFunction.java

   1 package tim.prune.function;
   2
   3 import java.io.InputStream;
   4 import java.net.URL;
   5 import java.util.ArrayList;
   6
   7 import javax.xml.parsers.SAXParser;
   8 import javax.xml.parsers.SAXParserFactory;
   9
  10 import tim.prune.App;
  11 import tim.prune.I18nManager;
  12 import tim.prune.data.DataPoint;
  13 import tim.prune.data.Field;
  14 import tim.prune.data.Latitude;
  15 import tim.prune.data.Longitude;
  16 import tim.prune.function.gpsies.GenericDownloaderFunction;
  17 import tim.prune.function.gpsies.GpsiesTrack;
  18
  19 /**
  20  * Function to load nearby point information from Wikipedia
  21  * according to the currently viewed area
  22  */
  23 public class GetWikipediaFunction extends GenericDownloaderFunction
  24 {
  25         /** Maximum number of results to get */
  26         private static final int MAX_RESULTS = 20;
  27         /** Maximum distance from point in km */
  28         private static final int MAX_DISTANCE = 15;
  29         /** Username to use for geonames queries */
  30         private static final String GEONAMES_USERNAME = "gpsprune";
  31
  32
  33         /**
  34          * Constructor
  35          * @param inApp App object
  36          */
  37         public GetWikipediaFunction(App inApp) {
  38                 super(inApp);
  39         }
  40
  41         /**
  42          * @return name key
  43          */
  44         public String getNameKey() {
  45                 return "function.getwikipedia";
  46         }
  47
  48         /**
  49          * @param inColNum index of column, 0 or 1
  50          * @return key for this column
  51          */
  52         protected String getColumnKey(int inColNum)
  53         {
  54                 if (inColNum == 0) return "dialog.wikipedia.column.name";
  55                 return "dialog.wikipedia.column.distance";
  56         }
  57
  58
  59         /**
  60          * Run method to call geonames in separate thread
  61          */
  62         public void run()
  63         {
  64                 _statusLabel.setText(I18nManager.getText("confirm.running"));
  65                 // Get coordinates from current point (if any) or from centre of screen
  66                 double lat = 0.0, lon = 0.0;
  67                 DataPoint point = _app.getTrackInfo().getCurrentPoint();
  68                 if (point == null)
  69                 {
  70                         double[] coords = _app.getViewport().getBounds();
  71                         lat = (coords[0] + coords[2]) / 2.0;
  72                         lon = (coords[1] + coords[3]) / 2.0;
  73                 }
  74                 else
  75                 {
  76                         lat = point.getLatitude().getDouble();
  77                         lon = point.getLongitude().getDouble();
  78                 }
  79
  80                 // Firstly try the local language
  81                 String lang = I18nManager.getText("wikipedia.lang");
  82                 submitSearch(lat, lon, lang);
  83                 // If we didn't get anything, try a secondary language
  84                 if (_trackListModel.isEmpty() && _errorMessage == null && lang.equals("als")) {
  85                         submitSearch(lat, lon, "de");
  86                 }
  87                 // If still nothing then try english
  88                 if (_trackListModel.isEmpty() && _errorMessage == null && !lang.equals("en")) {
  89                         submitSearch(lat, lon, "en");
  90                 }
  91
  92                 // Set status label according to error or "none found", leave blank if ok
  93                 if (_errorMessage == null && _trackListModel.isEmpty()) {
  94                         _errorMessage = I18nManager.getText("dialog.wikipedia.nonefound");
  95                 }
  96                 _statusLabel.setText(_errorMessage == null ? "" : _errorMessage);
  97         }
  98
  99         /**
 100          * Submit the search for the given parameters
 101          * @param inLat latitude
 102          * @param inLon longitude
 103          * @param inLang language code to use, such as en or de
 104          */
 105         private void submitSearch(double inLat, double inLon, String inLang)
 106         {
 107                 // Example http://api.geonames.org/findNearbyWikipedia?lat=47&lng=9
 108                 String urlString = "http://api.geonames.org/findNearbyWikipedia?lat=" +
 109                         inLat + "&lng=" + inLon + "&maxRows=" + MAX_RESULTS
 110                         + "&radius=" + MAX_DISTANCE + "&lang=" + inLang
 111                         + "&username=" + GEONAMES_USERNAME;
 112                 // Parse the returned XML with a special handler
 113                 GetWikipediaXmlHandler xmlHandler = new GetWikipediaXmlHandler();
 114                 InputStream inStream = null;
 115
 116                 try
 117                 {
 118                         URL url = new URL(urlString);
 119                         SAXParser saxParser = SAXParserFactory.newInstance().newSAXParser();
 120                         inStream = url.openStream();
 121                         saxParser.parse(inStream, xmlHandler);
 122                 }
 123                 catch (Exception e) {
 124                         _errorMessage = e.getClass().getName() + " - " + e.getMessage();
 125                 }
 126                 // Close stream and ignore errors
 127                 try {
 128                         inStream.close();
 129                 } catch (Exception e) {}
 130                 // Add track list to model
 131                 ArrayList<GpsiesTrack> trackList = xmlHandler.getTrackList();
 132                 _trackListModel.addTracks(trackList);
 133
 134                 // Show error message if any
 135                 if (_trackListModel.isEmpty())
 136                 {
 137                         String error = xmlHandler.getErrorMessage();
 138                         if (error != null && !error.equals(""))
 139                         {
 140                                 _app.showErrorMessageNoLookup(getNameKey(), error);
 141                                 _errorMessage = error;
 142                         }
 143                 }
 144         }
 145
 146         /**
 147          * Load the selected point(s)
 148          */
 149         protected void loadSelected()
 150         {
 151                 // Find the rows selected in the table and get the corresponding coords
 152                 int numSelected = _trackTable.getSelectedRowCount();
 153                 if (numSelected < 1) return;
 154                 int[] rowNums = _trackTable.getSelectedRows();
 155                 for (int i=0; i<numSelected; i++)
 156                 {
 157                         int rowNum = rowNums[i];
 158                         if (rowNum >= 0 && rowNum < _trackListModel.getRowCount())
 159                         {
 160                                 String coords = _trackListModel.getTrack(rowNum).getDownloadLink();
 161                                 String[] latlon = coords.split(",");
 162                                 if (latlon.length == 2)
 163                                 {
 164                                         DataPoint point = new DataPoint(new Latitude(latlon[0]), new Longitude(latlon[1]), null);
 165                                         point.setFieldValue(Field.WAYPT_NAME, _trackListModel.getTrack(rowNum).getTrackName(), false);
 166                                         _app.createPoint(point);
 167                                 }
 168                         }
 169                 }
 170                 // Close the dialog
 171                 _cancelled = true;
 172                 _dialog.dispose();
 173         }
 174 }