source: josm/trunk/src/org/openstreetmap/josm/io/OsmServerReader.java@ 1102

// License: GPL. Copyright 2007 by Immanuel Scholz and others
package org.openstreetmap.josm.io;

import static org.openstreetmap.josm.tools.I18n.tr;

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.zip.Inflater;
import java.util.zip.InflaterInputStream;
import java.util.zip.GZIPInputStream;

import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.gui.PleaseWaitDialog;

/**
 * This DataReader reads directly from the REST API of the osm server.
 * 
 * It supports plain text transfer as well as gzip or deflate encoded transfers;
 * if compressed transfers are unwanted, set property osm-server.use-compression
 * to false.
 *
 * @author imi
 */
abstract class OsmServerReader extends OsmConnection {
        /**
         * Open a connection to the given url and return a reader on the input stream
         * from that connection. In case of user cancel, return <code>null</code>.
         * @param urlStr The exact url to connect to.
         * @param pleaseWaitDlg
         * @return An reader reading the input stream (servers answer) or <code>null</code>.
         */
        protected InputStream getInputStream(String urlStr, PleaseWaitDialog pleaseWaitDlg) throws IOException {
                String version = Main.pref.get("osm-server.version", "0.5");
                urlStr = Main.pref.get("osm-server.url")+"/"+version+"/" + urlStr;
                System.out.println("download: "+urlStr);
                initAuthentication();
                URL url = new URL(urlStr);
                activeConnection = (HttpURLConnection)url.openConnection();
                if (cancel) {
                        activeConnection.disconnect();
                        return null;
                }
                
                if (Boolean.parseBoolean(Main.pref.get("osm-server.use-compression", "true")))
                        activeConnection.setRequestProperty("Accept-Encoding", "gzip, deflate");

                activeConnection.setConnectTimeout(15000);
                if (isAuthCancelled() && activeConnection.getResponseCode() == 401)
                        return null;
                if( activeConnection.getResponseCode() == 500 )
                {
                        throw new IOException(tr("Server returned internal error. Try a reduced area or retry after waiting some time."));
                }
//              System.out.println("got return: "+activeConnection.getResponseCode());

                String encoding = activeConnection.getContentEncoding();
                InputStream inputStream = new ProgressInputStream(activeConnection, pleaseWaitDlg);
                if (encoding != null && encoding.equalsIgnoreCase("gzip")) {
                        inputStream = new GZIPInputStream(inputStream);
                }
                else if (encoding != null && encoding.equalsIgnoreCase("deflate")) {
                        inputStream = new InflaterInputStream(inputStream, new Inflater(true));
                }
                return inputStream;
        }
}