bemap.OsmAPI.java Source code

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Here is the source code for bemap.OsmAPI.java

Source

/*
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package bemap;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.InputStreamReader;
import java.io.StringReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.text.DecimalFormat;
import java.util.ArrayList;
import org.json.JSONObject;
import javax.xml.parsers.*;
import org.openstreetmap.gui.jmapviewer.MapMarkerDot;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;

/**
 *
 * @author Micha
 */
public class OsmAPI {

    //0.0001 is a good value (about 5m)
    private static final double NODE_SEARCH_RADIUS = 0.0003;
    private final String USER_AGENT = "Mozilla/5.0";
    private final String DOMAIN = "http://api.openstreetmap.org";
    private final boolean SERVER_DEBUG = false;

    public OsmAPI() {

    }

    public ArrayList<OsmNode> getOSMSegments(double lat, double lon) throws Exception {

        ArrayList<OsmNode> OsmNodeList = new ArrayList<>();

        double left = lon - NODE_SEARCH_RADIUS;
        double bottom = lat - NODE_SEARCH_RADIUS;
        double right = lon + NODE_SEARCH_RADIUS;
        double top = lat + NODE_SEARCH_RADIUS;

        String url = DOMAIN + "/api/0.6/map?bbox=" + String.format("%.10f", left) + ","
                + String.format("%.10f", bottom) + "," + String.format("%.10f", right) + ","
                + String.format("%.10f", top);

        URL obj = new URL(url);
        HttpURLConnection con = (HttpURLConnection) obj.openConnection();

        // optional default is GET
        con.setRequestMethod("GET");

        //add request header
        con.setRequestProperty("User-Agent", USER_AGENT);

        int responseCode = con.getResponseCode();
        if (SERVER_DEBUG)
            BeMapEditor.mainWindow.append("Sending 'GET' request to URL : " + url + "\n");

        if (SERVER_DEBUG)
            BeMapEditor.mainWindow.append("Response Code : " + responseCode + "\n");

        BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
        String inputLine;
        StringBuffer response = new StringBuffer();

        while ((inputLine = in.readLine()) != null) {
            response.append(inputLine);
        }
        in.close();

        //print result
        String xml = response.toString();

        //if(SERVER_DEBUG) BeMapEditor.mainWindow.append(xml);

        Document doc = loadXMLFromString(xml);
        NodeList nList = doc.getElementsByTagName("node");

        for (int temp = 0; temp < nList.getLength(); temp++) {

            Node nNode = nList.item(temp);

            //System.out.println("\nCurrent Element :" + nNode.getNodeName());

            if (nNode.getNodeType() == Node.ELEMENT_NODE) {

                Element eElement = (Element) nNode;

                //System.out.println(eElement.getAttribute("id"));
                //System.out.println(eElement.getAttribute("lat"));
                //System.out.println(eElement.getAttribute("lon"));

                NodeList childList = eElement.getChildNodes();

                for (int i = 0; i < childList.getLength(); i++) {
                    Node childNode = childList.item(i);

                    if (childNode.getNodeType() == Node.ELEMENT_NODE) {
                        Element child = (Element) childNode;

                        if ("highway".equals(child.getAttribute("k"))) {
                            double lat1 = Double.parseDouble(eElement.getAttribute("lat"));
                            double lon1 = Double.parseDouble(eElement.getAttribute("lon"));
                            long id = Long.parseLong(eElement.getAttribute("id"));

                            OsmNode s = new OsmNode(id, lat1, lon1);
                            OsmNodeList.add(s);

                            //for debug
                            /*
                            MapMarkerDot m = new MapMarkerDot(lat1,lon1);
                            BeMapEditor.mainWindow.getMap().addMapMarker(m);
                            m.setVisible(true);
                            */
                        }
                    }
                }
            }
        }

        return OsmNodeList;
    }

    public static Document loadXMLFromString(String xml) throws Exception {
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();
        InputSource is = new InputSource(new StringReader(xml));
        return builder.parse(is);
    }

}