Java URL Download downloadGzipCompressedFile(URL url, File destination)

Description

Download the content provided at URL url and stores the result to a local file

License

GNU General Public License

Parameter

Parameter	Description
url	a parameter
destination	a parameter

Exception

Parameter	Description
IOException	an exception

Declaration

public static void downloadGzipCompressedFile(URL url, File destination)
        throws IOException 

Method Source Code

//package com.java2s;
/**//from  ww  w . j  a  va2  s .  c om
 *                    BioJava development code
 *
 * This code may be freely distributed and modified under the
 * terms of the GNU Lesser General Public Licence.  This should
 * be distributed with the code.  If you do not have a copy,
 * see:
 *
 *      http://www.gnu.org/copyleft/lesser.html
 *
 * Copyright for this code is held jointly by the individual
 * authors.  These should be listed in @author doc comments.
 *
 * For more information on the BioJava project and its aims,
 * or to join the biojava-l mailing list, visit the home page
 * at:
 *
 *      http://www.biojava.org/
 *
 * Created on Feb 23, 2012
 * Created by Andreas Prlic
 *
 * @since 3.0.2
 */

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.URL;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

public class Main {
    /** Download the content provided at URL url and stores the result to a local file
     * 
     * @param url
     * @param destination
     * @throws IOException
     */
    public static void downloadGzipCompressedFile(URL url, File destination)
            throws IOException {

        InputStream uStream = url.openStream();
        InputStream conn = new GZIPInputStream(uStream);

        File tempFile = File.createTempFile(getFilePrefix(destination), "."
                + getFileExtension(destination));

        try {
            //         System.out.println("downloading " + url + " to " + tempFile.getAbsolutePath());
            FileOutputStream outPut = new FileOutputStream(tempFile);
            GZIPOutputStream gzOutPut = new GZIPOutputStream(outPut);
            PrintWriter pw = new PrintWriter(gzOutPut);

            BufferedReader fileBuffer = new BufferedReader(
                    new InputStreamReader(conn));
            String line;
            while ((line = fileBuffer.readLine()) != null) {
                pw.println(line);
            }
            pw.flush();
            pw.close();

            outPut.flush();
            outPut.close();
            conn.close();
            uStream.close();
        } catch (Exception e) {
            e.printStackTrace();
            if (conn != null)
                conn.close();
            if (uStream != null)
                uStream.close();
            throw new IOException(e.getMessage());

        }
        // copy file name to **real** location (without the tmpFileName)
        // prepare destination
        //      System.out.println("copying to " + destination);

        copy(tempFile, destination);

        // delete the tmp file         
        tempFile.delete();

    }

    public static String getFilePrefix(File f) {
        String fileName = f.getName();
        String fname = "";

        int mid = fileName.indexOf(".");
        fname = fileName.substring(0, mid);

        return fname;
    }

    public static String getFileExtension(File f) {
        String fileName = f.getName();
        //String fname="";
        String ext = "";
        int mid = fileName.lastIndexOf(".");
        //fname=fileName.substring(0,mid);
        ext = fileName.substring(mid + 1, fileName.length());
        //System.out.println("File name ="+fname);
        //System.out.println("Extension ="+ext);
        return ext;
    }

    /** Copy the content of file A to B
     * 
     * @param src
     * @param dst
     * @throws IOException
     */
    public static void copy(File src, File dst) throws IOException {

        InputStream in = new FileInputStream(src);
        OutputStream out = new FileOutputStream(dst);

        // Transfer bytes from in to out
        byte[] buf = new byte[1024];
        int len;
        while ((len = in.read(buf)) > 0) {
            out.write(buf, 0, len);
        }
        in.close();
        out.close();
    }
}

Related

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2. downloadFileToGivenNameElseExtension( URLConnection urlConnection, String fileName)
3. downloadFromURL(String url)
4. downloadFromUrl(String urlString, PrintStream logger)
5. downloadFromUrl(URL url, String localFilename)
6. downloadHttp(String downloadURL, String basePath, String commonPathURL)
7. downloadImg(String urlPath, File file)
8. downloadMobiFromEpubUrl(String href)
9. downloadPageSource(String stringURL)