Version 3, August 2007

[GpsPrune.git] / tim / prune / load / xml / GpxHandler.java

diff --git a/tim/prune/load/xml/GpxHandler.java b/tim/prune/load/xml/GpxHandler.java
new file mode 100644 (file)
index 0000000..962b495
--- /dev/null
+++ b/tim/prune/load/xml/GpxHandler.java
@@ -0,0 +1,157 @@
+package tim.prune.load.xml;
+
+import java.util.ArrayList;
+
+import org.xml.sax.Attributes;
+import org.xml.sax.SAXException;
+
+import tim.prune.data.Field;
+
+
+/**
+ * Class for handling specifics of parsing Gpx files
+ */
+public class GpxHandler extends XmlHandler
+{
+       private boolean _insideName = false;
+       private boolean _insideElevation = false;
+       private boolean _insideTime = false;
+       private String _name = null, _latitude = null, _longitude = null;
+       private String _elevation = null;
+       private String _time = null;
+       private ArrayList _pointList = new ArrayList();
+
+
+       /**
+        * Receive the start of a tag
+        * @see org.xml.sax.ContentHandler#startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)
+        */
+       public void startElement(String uri, String localName, String qName,
+                       Attributes attributes) throws SAXException
+       {
+               // Read the parameters for waypoints and track points
+               if (qName.equalsIgnoreCase("wpt") || qName.equalsIgnoreCase("trkpt"))
+               {
+                       int numAttributes = attributes.getLength();
+                       for (int i=0; i<numAttributes; i++)
+                       {
+                               String att = attributes.getQName(i);
+                               if (att.equals("lat")) {_latitude = attributes.getValue(i);}
+                               else if (att.equals("lon")) {_longitude = attributes.getValue(i);}
+                       }
+                       _elevation = null;
+                       _name = null;
+                       _time = null;
+               }
+               else if (qName.equalsIgnoreCase("ele"))
+               {
+                       _insideElevation = true;
+               }
+               else if (qName.equalsIgnoreCase("name"))
+               {
+                       _insideName = true;
+               }
+               else if (qName.equalsIgnoreCase("time"))
+               {
+                       _insideTime = true;
+               }
+               super.startElement(uri, localName, qName, attributes);
+       }
+
+
+       /**
+        * Process end tag
+        * @see org.xml.sax.ContentHandler#endElement(java.lang.String, java.lang.String, java.lang.String)
+        */
+       public void endElement(String uri, String localName, String qName)
+       throws SAXException
+       {
+               if (qName.equalsIgnoreCase("wpt") || qName.equalsIgnoreCase("trkpt"))
+               {
+                       processPoint();
+               }
+               else if (qName.equalsIgnoreCase("ele"))
+               {
+                       _insideElevation = false;
+               }
+               else if (qName.equalsIgnoreCase("name"))
+               {
+                       _insideName = false;
+               }
+               else if (qName.equalsIgnoreCase("time"))
+               {
+                       _insideTime = false;
+               }
+               super.endElement(uri, localName, qName);
+       }
+
+
+       /**
+        * Process character text (inside tags or between them)
+        * @see org.xml.sax.ContentHandler#characters(char[], int, int)
+        */
+       public void characters(char[] ch, int start, int length)
+                       throws SAXException
+       {
+               String value = new String(ch, start, length);
+               if (_insideName) {_name = checkCharacters(_name, value);}
+               else if (_insideElevation) {_elevation = checkCharacters(_elevation, value);}
+               else if (_insideTime) {_time = checkCharacters(_time, value);}
+               super.characters(ch, start, length);
+       }
+
+
+       /**
+        * Check to concatenate partially-received values, if necessary
+        * @param inVariable variable containing characters received until now
+        * @param inValue new value received
+        * @return concatenation
+        */
+       private static String checkCharacters(String inVariable, String inValue)
+       {
+               if (inVariable == null) {return inValue;}
+               return inVariable + inValue;
+       }
+
+
+       /**
+        * Process a point, either a waypoint or track point
+        */
+       private void processPoint()
+       {
+               // Put the values into a String array matching the order in getFieldArray()
+               String[] values = new String[5];
+               values[0] = _latitude; values[1] = _longitude;
+               values[2] = _elevation; values[3] = _name;
+               values[4] = _time;
+               _pointList.add(values);
+       }
+
+
+       /**
+        * @see tim.prune.load.xml.XmlHandler#getFieldArray()
+        */
+       public Field[] getFieldArray()
+       {
+               final Field[] fields = {Field.LATITUDE, Field.LONGITUDE, Field.ALTITUDE,
+                       Field.WAYPT_NAME, Field.TIMESTAMP};
+               return fields;
+       }
+
+
+       /**
+        * Return the parsed information as a 2d array
+        * @see tim.prune.load.xml.XmlHandler#getDataArray()
+        */
+       public String[][] getDataArray()
+       {
+               int numPoints = _pointList.size();
+               // construct data array
+               String[][] result = new String[numPoints][];
+               for (int i=0; i<numPoints; i++)
+               {
+                       result[i] = (String[]) _pointList.get(i);
+               }
+               return result;
+       }
+}