source: josm/src/org/openstreetmap/josm/io/RawCsvReader.java@ 99

package org.openstreetmap.josm.io;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.Reader;
import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedList;
import java.util.StringTokenizer;

import org.jdom.JDOMException;
import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.data.coor.LatLon;
import org.openstreetmap.josm.gui.layer.RawGpsLayer.GpsPoint;

/**
 * Read raw information from a csv style file (as defined in the preferences).
 * @author imi
 */
public class RawCsvReader {

        /**
         * Reader to read the input from.
         */
        private BufferedReader in;

        public RawCsvReader(Reader in) {
                this.in = new BufferedReader(in);
        }

        public Collection<GpsPoint> parse() throws JDOMException, IOException {
                Collection<GpsPoint> data = new LinkedList<GpsPoint>();
                String formatStr = Main.pref.get("csv.importstring");
                if (formatStr == null)
                        formatStr = in.readLine();
                if (formatStr == null)
                        throw new JDOMException("Could not detect data format string.");

                // get delimiter
                String delim = ",";
                for (int i = 0; i < formatStr.length(); ++i) {
                        if (!Character.isLetterOrDigit(formatStr.charAt(i))) {
                                delim = ""+formatStr.charAt(i);
                                break;
                        }
                }

                // convert format string
                ArrayList<String> format = new ArrayList<String>();
                for (StringTokenizer st = new StringTokenizer(formatStr, delim); st.hasMoreTokens();) {
                        String token = st.nextToken();
                        if (!token.equals("lat") && !token.equals("lon") && !token.equals("time"))
                                token = "ignore";
                        format.add(token);
                }

                // test for completness
                if (!format.contains("lat") || !format.contains("lon")) {
                        if (Main.pref.get("csv.importstring").equals(""))
                                throw new JDOMException("Format string in data is incomplete or not found. Try setting an manual format string in Preferences.");
                        throw new JDOMException("Format string is incomplete. Need at least 'lat' and 'lon' specification");
                }

                int lineNo = 0;
                try {
                        for (String line = in.readLine(); line != null; line = in.readLine()) {
                                lineNo++;
                                StringTokenizer st = new StringTokenizer(line, delim);
                                double lat = 0, lon = 0;
                                String time = null;
                                for (String token : format) {
                                        if (token.equals("lat"))
                                                lat = Double.parseDouble(st.nextToken());
                                        else if (token.equals("lon"))
                                                lon = Double.parseDouble(st.nextToken());
                                        else if (token.equals("time"))
                                                time = (time == null?"":(time+" ")) + st.nextToken();
                                        else if (token.equals("ignore"))
                                                st.nextToken();
                                        else
                                                throw new JDOMException("Unknown data type: '"+token+"'."+(Main.pref.get("csv.importstring").equals("") ? " Maybe add an format string in preferences." : ""));
                                }
                                data.add(new GpsPoint(new LatLon(lat, lon), time));
                        }
                } catch (RuntimeException e) {
                        throw new JDOMException("Parsing error in line "+lineNo, e);
                }
                return data;
        }
}