com.grosscommerce.ICEcat.utilities.Downloader.java Source code

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Here is the source code for com.grosscommerce.ICEcat.utilities.Downloader.java

Source

/**
 * This program is free software:  you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation.
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Copyright 2011 GrossCommerce
 */
package com.grosscommerce.ICEcat.utilities;

import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.ProtocolException;
import java.net.URL;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.zip.GZIPInputStream;
import org.apache.commons.codec.binary.Base64;

/**
 * Used for downloading binary data.
 * @author Anykey Skovorodkin
 */
public abstract class Downloader {
    public static void download(String urlFrom, String login, String pwd, OutputStream destStream)
            throws Exception {
        try {
            HttpURLConnection uc = prepareConnection(urlFrom, login, pwd);

            uc.connect();

            if (uc.getResponseCode() != HttpURLConnection.HTTP_OK) {
                Logger.getLogger(Downloader.class.getName()).log(Level.INFO, "Error, code: {0}, message {1}",
                        new Object[] { uc.getResponseCode(), uc.getResponseMessage() });

                return;
            }

            BufferedInputStream is = null;

            if ((uc.getContentEncoding() != null && uc.getContentEncoding().toLowerCase().equals("gzip"))
                    || uc.getContentType() != null && uc.getContentType().toLowerCase().contains("gzip")) {
                is = new BufferedInputStream(new GZIPInputStream(uc.getInputStream()));

                Logger.getLogger(Downloader.class.getName()).log(Level.INFO, "Will download gzip data from: {0}",
                        urlFrom);
            } else {
                is = new BufferedInputStream(uc.getInputStream());

                Logger.getLogger(Downloader.class.getName()).log(Level.INFO,
                        "Will download not compressed data from:{0}", urlFrom);
            }

            StreamsHelper.copy(is, destStream);
            destStream.flush();

        } catch (Exception ex) {
            Logger.getLogger(Downloader.class.getName()).log(Level.SEVERE, "URL: " + urlFrom, ex);

            throw ex;
        }
    }

    public static byte[] download(String urlFrom, String login, String pwd) throws Throwable {
        ByteArrayOutputStream os = new ByteArrayOutputStream();
        download(urlFrom, login, pwd, os);
        byte[] result = os.toByteArray();
        os.close();
        Logger.getLogger(Downloader.class.getName()).log(Level.INFO, "Downloaded {0} byte(s)",
                new Object[] { result.length });

        return result;
    }

    private static HttpURLConnection prepareConnection(String urlFrom, String login, String pwd)
            throws ProtocolException, IOException, MalformedURLException {
        URL url = new URL(urlFrom);
        HttpURLConnection uc = (HttpURLConnection) url.openConnection();
        // set up url connection to get retrieve information back
        uc.setRequestMethod("GET");
        uc.setDoInput(true);
        String val = (new StringBuffer(login).append(":").append(pwd)).toString();
        byte[] base = val.getBytes();
        String authorizationString = "Basic " + Base64.encodeBase64String(base);
        uc.setRequestProperty("Authorization", authorizationString);
        uc.setRequestProperty("Accept-Encoding", "gzip, xml");
        return uc;
    }
}