// This software is released into the Public Domain. See copying.txt for details.
package org.openstreetmap.osmosis.xml.v0_6;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Collections;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.zip.Inflater;
import java.util.zip.InflaterInputStream;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.openstreetmap.osmosis.core.OsmosisRuntimeException;
import org.openstreetmap.osmosis.core.OsmosisConstants;
import org.openstreetmap.osmosis.core.container.v0_6.BoundContainer;
import org.openstreetmap.osmosis.core.domain.v0_6.Bound;
import org.openstreetmap.osmosis.core.task.v0_6.RunnableSource;
import org.openstreetmap.osmosis.core.task.v0_6.Sink;
import org.openstreetmap.osmosis.core.util.MultiMemberGZIPInputStream;
import org.openstreetmap.osmosis.xml.v0_6.impl.OsmHandler;
import org.openstreetmap.osmosis.xml.v0_6.impl.XmlConstants;
/**
* An OSM data source reading from an osm-xml file from the
* OpenStreetMap-server.
*
* @author <a href="mailto:Marcus@Wolschon.biz">Marcus Wolschon</a>
*/
public class XmlDownloader implements RunnableSource {
/**
* The http-response-code for OK.
*/
private static final int RESPONSECODE_OK = 200;
/**
* My logger for debug- and error-output.
*/
private static Logger log = Logger.getLogger(XmlDownloader.class.getName());
/**
* The timeout we use for the HttpURLConnection.
*/
private static final int TIMEOUT = 15000;
/**
* Where to deliver the loaded data.
*/
private Sink mySink;
/**
* Left longitude of the bounding box.
*/
private double myLeft;
/**
* Right longitude of the bounding box.
*/
private double myRight;
/**
* Top latitude of the bounding box.
*/
private double myTop;
/**
* Bottom latitude of the bounding box.
*/
private double myBottom;
/**
* The base url of the server.
* Defaults to. "http://www.openstreetmap.org/api/0.5".
*/
private String myBaseUrl = XmlConstants.DEFAULT_URL;
/**
* The http connection used to retrieve data.
*/
private HttpURLConnection myActiveConnection;
/**
* The stream providing response data.
*/
private InputStream responseStream;
/**
* Creates a new instance with the specified geographical coordinates.
*
* @param left
* The longitude marking the left edge of the bounding box.
* @param right
* The longitude marking the right edge of the bounding box.
* @param top
* The latitude marking the top edge of the bounding box.
* @param bottom
* The latitude marking the bottom edge of the bounding box.
* @param baseUrl
* (optional) The base url of the server (eg.
* http://www.openstreetmap.org/api/0.5).
*/
public XmlDownloader(final double left,
final double right,
final double top,
final double bottom,
final String baseUrl) {
this.myLeft = Math.min(left, right);
this.myRight = Math.max(left, right);
this.myTop = Math.max(top, bottom);
this.myBottom = Math.min(top, bottom);
if (baseUrl != null) {
this.myBaseUrl = baseUrl;
}
}
/**
* {@inheritDoc}
*/
public void setSink(final Sink aSink) {
this.mySink = aSink;
}
/**
* Cleans up any resources remaining after completion.
*/
private void cleanup() {
if (myActiveConnection != null) {
try {
myActiveConnection.disconnect();
} catch (Exception e) {
log.log(Level.SEVERE, "Unable to disconnect.", e);
}
myActiveConnection = null;
}
if (responseStream != null) {
try {
responseStream.close();
} catch (IOException e) {
log.log(Level.SEVERE, "Unable to close response stream.", e);
}
responseStream = null;
}
}
/**
* Creates a new SAX parser.
*
* @return The newly created SAX parser.
*/
private SAXParser createParser() {
try {
return SAXParserFactory.newInstance().newSAXParser();
} catch (ParserConfigurationException e) {
throw new OsmosisRuntimeException("Unable to create SAX Parser.", e);
} catch (SAXException e) {
throw new OsmosisRuntimeException("Unable to create SAX Parser.", e);
}
}
/**
* Reads all data from the server and send it to the {@link Sink}.
*/
public void run() {
try {
mySink.initialize(Collections.<String, Object>emptyMap());
SAXParser parser = createParser();
InputStream inputStream =
getInputStream(myBaseUrl + "/map?bbox=" + myLeft + "," + myBottom + "," + myRight + "," + myTop);
// First send the Bound down the pipeline
mySink.process(new BoundContainer(new Bound(myRight, myLeft, myTop, myBottom, myBaseUrl)));
try {
parser.parse(inputStream, new OsmHandler(mySink, true));
} finally {
inputStream.close();
inputStream = null;
}
mySink.complete();
} catch (SAXParseException e) {
throw new OsmosisRuntimeException(
"Unable to parse xml"
+ ". publicId=(" + e.getPublicId()
+ "), systemId=(" + e.getSystemId()
+ "), lineNumber=" + e.getLineNumber()
+ ", columnNumber=" + e.getColumnNumber() + ".",
e);
} catch (SAXException e) {
throw new OsmosisRuntimeException("Unable to parse XML.", e);
} catch (IOException e) {
throw new OsmosisRuntimeException("Unable to read XML.", e);
} finally {
mySink.release();
cleanup();
}
}
/**
* Open a connection to the given url and return a reader on the input
* stream from that connection.
*
* @param pUrlStr
* The exact url to connect to.
* @return An reader reading the input stream (servers answer) or
* <code>null</code>.
* @throws IOException
* on io-errors
*/
private InputStream getInputStream(final String pUrlStr) throws IOException {
URL url;
int responseCode;
String encoding;
url = new URL(pUrlStr);
myActiveConnection = (HttpURLConnection) url.openConnection();
myActiveConnection.setRequestProperty("User-Agent", "Osmosis/" + OsmosisConstants.VERSION);
myActiveConnection.setRequestProperty("Accept-Encoding", "gzip, deflate");
responseCode = myActiveConnection.getResponseCode();
if (responseCode != RESPONSECODE_OK) {
String message;
String apiErrorMessage;
apiErrorMessage = myActiveConnection.getHeaderField("Error");
if (apiErrorMessage != null) {
message = "Received API HTTP response code " + responseCode
+ " with message \"" + apiErrorMessage
+ "\" for URL \"" + pUrlStr + "\".";
} else {
message = "Received API HTTP response code " + responseCode
+ " for URL \"" + pUrlStr + "\".";
}
throw new OsmosisRuntimeException(message);
}
myActiveConnection.setConnectTimeout(TIMEOUT);
encoding = myActiveConnection.getContentEncoding();
responseStream = myActiveConnection.getInputStream();
if (encoding != null && encoding.equalsIgnoreCase("gzip")) {
responseStream = new MultiMemberGZIPInputStream(responseStream);
} else if (encoding != null && encoding.equalsIgnoreCase("deflate")) {
responseStream = new InflaterInputStream(responseStream, new Inflater(true));
}
return responseStream;
}
}