tim/prune/load/xml/XmlFileLoader.java

   1 package tim.prune.load.xml;
   2
   3 import java.io.File;
   4 import javax.swing.JFrame;
   5 import javax.swing.JOptionPane;
   6 import javax.xml.parsers.SAXParser;
   7 import javax.xml.parsers.SAXParserFactory;
   8
   9 import org.xml.sax.Attributes;
  10 import org.xml.sax.SAXException;
  11 import org.xml.sax.helpers.DefaultHandler;
  12 import tim.prune.App;
  13 import tim.prune.I18nManager;
  14 import tim.prune.data.Altitude;
  15
  16 /**
  17  * Class for handling loading of Xml files, and passing the
  18  * loaded data back to the App object
  19  */
  20 public class XmlFileLoader extends DefaultHandler implements Runnable
  21 {
  22         private File _file = null;
  23         private App _app = null;
  24         private JFrame _parentFrame = null;
  25         private XmlHandler _handler = null;
  26         private String _unknownType = null;
  27
  28
  29         /**
  30          * Constructor
  31          * @param inApp Application object to inform of track load
  32          * @param inParentFrame parent frame to reference for dialogs
  33          */
  34         public XmlFileLoader(App inApp, JFrame inParentFrame)
  35         {
  36                 _app = inApp;
  37                 _parentFrame = inParentFrame;
  38         }
  39
  40
  41         /**
  42          * Open the selected file and show the GUI dialog to select load options
  43          * @param inFile File to open
  44          */
  45         public void openFile(File inFile)
  46         {
  47                 _file = inFile;
  48                 _handler = null;
  49                 _unknownType = null;
  50                 // start new thread in case xml parsing is time-consuming
  51                 new Thread(this).start();
  52         }
  53
  54
  55         /**
  56          * Run method, to parse the file
  57          * @see java.lang.Runnable#run()
  58          */
  59         public void run()
  60         {
  61                 try
  62                 {
  63                         // Construct a SAXParser and use this as a default handler
  64                         SAXParser saxParser = SAXParserFactory.newInstance().newSAXParser();
  65                         saxParser.parse(_file, this);
  66
  67                         // Check whether handler was properly instantiated
  68                         if (_handler == null)
  69                         {
  70                                 // Wasn't either kml or gpx
  71                                 JOptionPane.showMessageDialog(_parentFrame,
  72                                         I18nManager.getText("error.load.unknownxml") + " " + _unknownType,
  73                                         I18nManager.getText("error.load.dialogtitle"), JOptionPane.ERROR_MESSAGE);
  74                         }
  75                         else
  76                         {
  77                                 // Pass information back to app
  78                                 _app.informDataLoaded(_handler.getFieldArray(), _handler.getDataArray(),
  79                                         Altitude.FORMAT_METRES, _file.getName());
  80                         }
  81                 }
  82                 catch (Exception e)
  83                 {
  84                         // Show error dialog
  85                         JOptionPane.showMessageDialog(_parentFrame,
  86                                 I18nManager.getText("error.load.othererror") + " " + e.getMessage(),
  87                                 I18nManager.getText("error.load.dialogtitle"), JOptionPane.ERROR_MESSAGE);
  88                 }
  89         }
  90
  91
  92         /**
  93          * Receive a tag
  94          * @see org.xml.sax.ContentHandler#startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)
  95          */
  96         public void startElement(String uri, String localName, String qName,
  97                 Attributes attributes) throws SAXException
  98         {
  99                 // Check for "kml" or "gpx" tags
 100                 if (_handler == null)
 101                 {
 102                         if (qName.equals("kml")) {_handler = new KmlHandler();}
 103                         else if (qName.equals("gpx")) {_handler = new GpxHandler();}
 104                         else if (_unknownType == null && qName != null && !qName.equals(""))
 105                         {
 106                                 _unknownType = qName;
 107                         }
 108                 }
 109                 else
 110                 {
 111                         // Handler instantiated so pass tags on to it
 112                         _handler.startElement(uri, localName, qName, attributes);
 113                 }
 114                 super.startElement(uri, localName, qName, attributes);
 115         }
 116
 117
 118         /**
 119          * Receive characters, either between or inside tags
 120          * @see org.xml.sax.ContentHandler#characters(char[], int, int)
 121          */
 122         public void characters(char[] ch, int start, int length)
 123                 throws SAXException
 124         {
 125                 if (_handler != null)
 126                 {
 127                         // Handler instantiated so pass tags on to it
 128                         _handler.characters(ch, start, length);
 129                 }
 130                 super.characters(ch, start, length);
 131         }
 132
 133
 134         /**
 135          * Receive end of element
 136          * @see org.xml.sax.ContentHandler#endElement(java.lang.String, java.lang.String, java.lang.String)
 137          */
 138         public void endElement(String uri, String localName, String qName)
 139                 throws SAXException
 140         {
 141                 if (_handler != null)
 142                 {
 143                         // Handler instantiated so pass tags on to it
 144                         _handler.endElement(uri, localName, qName);
 145                 }
 146                 super.endElement(uri, localName, qName);
 147         }
 148 }