Application: gvSIG desktop

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2008 Infrastructures and Transports Department

 * of the Valencian Government (CIT)

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 */

/*

 * AUTHORS (In addition to CIT):

 * 2010 Prodevelop S.L. main development

 * http://www.prodevelop.es

 */

package org.gvsig.remoteclient.arcims.utils;

import java.io.BufferedOutputStream;

import java.io.DataOutputStream;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStreamWriter;

import java.net.ConnectException;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.ProtocolException;

import java.net.URL;

import java.net.UnknownHostException;

import java.util.Hashtable;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.gvsig.remoteclient.arcims.ArcImsStatus;

import org.gvsig.remoteclient.arcims.exceptions.ArcImsException;

/**

 * These download methods derive from those in

 * <tt>org.gvsig.remoteClient.arcims.utils.Utilities<tt>

 * and have been modified to prevent multiple downloads of the same image when

 * using an ArcIMS server, because the remote image's URL is not the

 * same when requesting the same map twice.

 *

 * @author jldominguez

 *

 */

/**

 * @author jsanz

 * @author vsanjaime version 2.0

 */

public class ArcImsDownloadUtils {

        private static Logger logger = LoggerFactory.getLogger(ArcImsDownloadUtils.class

                        .getName());

        private static Hashtable<URL, String> downloadedFiles;

        private static final String tempDirectoryPath = System

                        .getProperty("java.io.tmpdir")

                        + "/tmp-andami";

        /**

         * Returns the content of this URL as a file from the file system.<br>

         * <p>

         * If the URL has been already downloaded in this session and notified to

         * the system using the static <b>Utilities.addDownloadedURL(URL)</b>

         * method, it can be restored faster from the file system avoiding to

         * download it again.

         * </p>

         * 

         * @param virtualUrl

         * @param override

         *            If false, the file won't be downloaded

         * @return File containing this URL's content or null if no file was found.

         */

        private static File getPreviousDownloadedURL(URL virtualUrl,

                        boolean override) {

                File f = null;

                if ((downloadedFiles != null)

                                && downloadedFiles.containsKey(virtualUrl) && !override) {

                        String filePath = (String) downloadedFiles.get(virtualUrl);

                        f = new File(filePath);

                }

                return f;

        }

        /**

         * Returns the content of this URL as a file from the file system.<br>

         * <p>

         * If the URL has been already downloaded in this session and notified to

         * the system using the static <b>Utilities.addDownloadedURL(URL)</b>

         * method, it can be restored faster from the file system avoiding to

         * download it again.

         * </p>

         * This overrided method doesn't require the boolean parameter

         * 

         * @see #getPreviousDownloadedURL(URL, boolean)

         * @param virtualUrl

         * @return File containing this URL's content or null if no file was found.

         */

        private static File getPreviousDownloadedURL(URL virtualUrl) {

                return getPreviousDownloadedURL(virtualUrl, false);

        }

        /**

         * Downloads an URL into a temporary file that is removed the next time the

         * tempFileManager class is called, which means the next time gvSIG is

         * launched.

         * 

         * @param url

         * @param virtualURL

         *            The virtual URL that identifies the file in the internal cache

         * @param filePath

         *            Where the file will be downloaded

         * @return File object of the downloaded file

         * @throws IOException

         * @throws ServerErrorResponseException

         * @throws ConnectException

         * @throws UnknownHostException

         */

        public static File downloadFile(URL url, URL virtualURL, String filePath)

                        throws IOException, ConnectException, UnknownHostException {

                File f = null;

                long t1 = System.currentTimeMillis();

                try {

                        if ((f = getPreviousDownloadedURL(virtualURL)) == null) {

                                long t3 = System.currentTimeMillis();

                                File tempDirectory = new File(tempDirectoryPath);

                                if (!tempDirectory.exists()) {

                                        tempDirectory.mkdir();

                                }

                                // f = new File(tempDirectoryPath + "/" + filePath);

                                String fName = normalizeFileName(filePath);

                                f = new File(tempDirectoryPath + "/" + fName);

                                logger.info("downloading '" + url.toString() + "' to: "

                                                + f.getAbsolutePath());

                                f.deleteOnExit();

                                DataOutputStream dos = new DataOutputStream(

                                                new BufferedOutputStream(new FileOutputStream(f)));

                                byte[] buffer = new byte[1024 * 256];

                                InputStream is = url.openStream();

                                long readed = 0;

                                for (int i = is.read(buffer); i > 0; i = is.read(buffer)) {

                                        dos.write(buffer, 0, i);

                                        readed += i;

                                }

                                dos.close();

                                addDownloadedURL(virtualURL, f.getAbsolutePath());

                                long t4 = System.currentTimeMillis();

                                System.err.println("Download time: " + (t4 - t3));

                        }

                } catch (IOException io) {

                        io.printStackTrace();

                }

                // Avoid possible conflits caused by multiple application instances.

                if (!f.exists()) {

                        downloadedFiles.remove(virtualURL);

                        f = downloadFile(url, virtualURL, filePath);

                }

                long t2 = System.currentTimeMillis();

                System.err.println("Total download method time: " + (t2 - t1));

                return f;

        }

        /**

         * Downloads an URL into a temporary file that is removed the next time the

         * tempFileManager class is called, which means the next time gvSIG is

         * launched.

         * 

         * @param url

         * @param filePath

         *            Where the file will be downloaded

         * @return File object of the downloaded file

         * @throws IOException

         * @throws ServerErrorResponseException

         * @throws ConnectException

         * @throws UnknownHostException

         */

        public static File downloadFile(URL url, String filePath)

                        throws IOException, ConnectException, UnknownHostException {

                File f = null;

                long t1 = System.currentTimeMillis();

                try {

                        long t3 = System.currentTimeMillis();

                        File tempDirectory = new File(tempDirectoryPath);

                        if (!tempDirectory.exists()) {

                                tempDirectory.mkdir();

                        }

                        // f = new File(tempDirectoryPath + "/" + filePath);

                        String fName = normalizeFileName(filePath);

                        f = new File(tempDirectoryPath + "/" + fName);

                        logger.info("downloading '" + url.toString() + "' to: "

                                        + f.getAbsolutePath());

                        f.deleteOnExit();

                        DataOutputStream dos = new DataOutputStream(

                                        new BufferedOutputStream(new FileOutputStream(f)));

                        byte[] buffer = new byte[1024 * 256];

                        InputStream is = url.openStream();

                        long readed = 0;

                        for (int i = is.read(buffer); i > 0; i = is.read(buffer)) {

                                dos.write(buffer, 0, i);

                                readed += i;

                        }

                        dos.close();

                        long t4 = System.currentTimeMillis();

                        System.err.println("Download time: " + (t4 - t3));

                } catch (IOException io) {

                        io.printStackTrace();

                }

                long t2 = System.currentTimeMillis();

                System.err.println("Total download method time: " + (t2 - t1));

                return f;

        }

        /**

         * Adds an URL to the table of downloaded files for further uses. If the URL

         * already exists in the table its filePath value is updated to the new one

         * and the old file itself is removed from the file system.

         * 

         * @param virtualURL

         * @param filePath

         */

        private static void addDownloadedURL(URL virtualURL, String filePath) {

                if (downloadedFiles == null) {

                        downloadedFiles = new Hashtable<URL, String>();

                }

                String fileName = (String) downloadedFiles.put(virtualURL, filePath);

                if (fileName != null) {

                        File f = new File(fileName);

                        if (f.exists()) {

                                f.delete();

                        }

                }

        }

        /**

         * Sends a XML request to the server as a String and returns the server's

         * response as a File object

         * 

         * @param url

         *            server's URL

         * @param req

         *            XML request as a String

         * @param fName

         *            the name of the local file which will keep the server's

         *            response

         * @param override

         *            this boolean sets if the download will be done (true)

         * @return File object associated to the server's response (and it's local

         *         name is fName)

         * @throws ArcImsException

         */

        public static File doRequestPost(URL url, String req, String fName,

                        boolean override) throws ArcImsException {

                File f = null;

                URL virtualUrl = getVirtualRequestUrlFromUrlAndRequest(url, req);

                if ((f = getPreviousDownloadedURL(virtualUrl, override)) == null) {

                        File tempDirectory = new File(tempDirectoryPath);

                        if (!tempDirectory.exists()) {

                                tempDirectory.mkdir();

                        }

                        String nfName = normalizeFileName(fName);

                        f = new File(tempDirectoryPath + "/" + nfName);

                        // f = new File(tempDirectoryPath + "/" + fName + "."

                        // + System.currentTimeMillis());

                        f.deleteOnExit();

                        logger.info("downloading '" + url.toString() + "' to: "

                                        + f.getAbsolutePath());

                        try {

                                HttpURLConnection conn = (HttpURLConnection) url

                                                .openConnection();

                                conn.setDoOutput(true);

                                conn.setRequestMethod("POST");

                                conn.setRequestProperty("Content-type",

                                                "application/x-www-form-urlencoded");

                                conn.setRequestProperty("Content-length", "" + req.length());

                                OutputStreamWriter wr = new OutputStreamWriter(conn

                                                .getOutputStream());

                                wr.write(req);

                                wr.flush();

                                // Get the response

                                DataOutputStream dos = new DataOutputStream(

                                                new BufferedOutputStream(new FileOutputStream(f)));

                                byte[] buffer = new byte[1024 * 256];

                                InputStream is = conn.getInputStream();

                                long readed = 0;

                                for (int i = is.read(buffer); i > 0; i = is.read(buffer)) {

                                        dos.write(buffer, 0, i);

                                        readed += i;

                                }

                                dos.close();

                                is.close();

                                wr.close();

                                addDownloadedURL(virtualUrl, f.getAbsolutePath());

                        } catch (ConnectException ce) {

                                logger.error("Timed out error", ce);

                                throw new ArcImsException("arcims_server_timeout");

                        } catch (FileNotFoundException fe) {

                                logger.error("FileNotFound Error", fe);

                                throw new ArcImsException("arcims_server_error");

                        } catch (IOException e) {

                                logger.error("IO Error", e);

                                throw new ArcImsException("arcims_server_error");

                        }

                }

                // Avoid possible conflits caused by multiple application instances.

                if (!f.exists()) {

                        downloadedFiles.remove(virtualUrl);

                        f = doRequestPost(url, req, fName, override);

                }

                return f;

        }

        private static String normalizeFileName(String name) {

                String ret = new String();

                int indPoint = name.lastIndexOf(".");

                ret = name.substring(0, indPoint);

                ret += ("-" + System.currentTimeMillis());

                ret += ("." + name.substring(indPoint + 1));

                return ret;

        }

        /**

         * Sends a XML request to the server as a String and returns the server's

         * response as a File object

         * 

         * @param url

         *            server's URL

         * @param req

         *            XML request as a String

         * @param fName

         *            the name of the local file which will keep the server's

         *            response

         * @return File object associated to the server's response (and it's local

         *         name is fName)

         * @throws ArcImsException

         */

        public static File doRequestPost(URL url, String req, String fName)

                        throws ArcImsException {

                return doRequestPost(url, req, fName, false);

        }

        /**

         * Sends a POST request to a specified URL and gets a BufferedReader of the

         * contents

         * 

         * @param url

         * @param post

         * @return BufferedReaded

         * @throws ArcImsException

         */

        public static InputStream getRemoteIS(URL url, String post)

                        throws ArcImsException {

                InputStream lector = null;

                try {

                        HttpURLConnection conn = (HttpURLConnection) url.openConnection();

                        conn.setDoOutput(true);

                        conn.setRequestMethod("POST");

                        conn.setRequestProperty("Content-type",

                                        "application/x-www-form-urlencoded");

                        conn.setRequestProperty("Content-length", "" + post.length());

                        OutputStreamWriter wr = new OutputStreamWriter(conn

                                        .getOutputStream());

                        // Do the POST request

                        wr.write(post);

                        wr.flush();

                        // Get the response

                        logger.info("downloading '" + url.toString());

                        lector = conn.getInputStream();

                } catch (ConnectException e) {

                        logger.error("Timed out error", e);

                        throw new ArcImsException("arcims_server_timeout");

                } catch (ProtocolException e) {

                        logger.error(e.getMessage(), e);

                        throw new ArcImsException("arcims_server_error");

                } catch (IOException e) {

                        logger.error(e.getMessage(), e);

                        throw new ArcImsException("arcims_server_error");

                }

                return lector;

        }

        /**

         * Returns a virtual URL from status to emulate WMS requests to make unique

         * requests for every image gvSIG downloads.

         * 

         * @param status

         * @see org.gvsig.remoteClient.arcims.utils.ArcImsStatus

         * @return URL with the virtual link

         */

        public static URL getVirtualUrlFromStatus(ArcImsStatus status) {

                URL u = null;

                String r = "http://arcims.image.virtual.url/";

                r = r + "?Server=";

                r = r + status.getServerURL();

                r = r + "&Service=";

                r = r + status.getServiceName();

                r = r + "&LayerIds=";

                r = r + status.getLayerIds().toString();

                r = r + "&Extent=";

                r = r + status.getEnvelopeRect().toString();

                r = r + "&Format=";

                r = r + status.getFormat();

                try {

                        u = new URL(r);

                } catch (MalformedURLException e) {

                        System.err.println("Error in method getVirtualUrlFromStatus: "

                                        + e.getMessage());

                }

                return u;

        }

        /**

         * Returns a virtual URL from status to emulate WMS requests to make unique

         * requests for every image gvSIG downloads.

         * 

         * @param url

         * @param request

         * @return URL with the virtual link

         */

        public static URL getVirtualRequestUrlFromUrlAndRequest(URL url,

                        String request) {

                URL u = null;

                String r = "http://arcims.request.virtual.url/";

                r = r + "Url=" + url.toString();

                r = r + "&Request=";

                r = r + request;

                try {

                        u = new URL(r);

                } catch (MalformedURLException e) {

                        System.err.println("Error in methos getVirtualUrlFromStatus: "

                                        + e.getMessage());

                }

                return u;

        }

}