org.pepstock.jem.util.ZipUtil.java Source code

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Here is the source code for org.pepstock.jem.util.ZipUtil.java

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/**
JEM, the BEE - Job Entry Manager, the Batch Execution Environment
Copyright (C) 2012-2015   Andrea "Stock" Stocchero
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 3 of the License, or
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, see <http://www.gnu.org/licenses/>.
*/
package org.pepstock.jem.util;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;

import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream;
import org.apache.commons.io.IOUtils;

/**
 * Utility to zip a complete folder to a output stream
 * 
 * @author Andrea "Stock" Stocchero
 * @version 1.0   
 *
 */
public class ZipUtil {

    /**
     * To avoid any instatiation
     */
    private ZipUtil() {

    }

    /** 
      * Creates a zip output stream  at the specified path with the contents of the specified directory. 
      * 
      * @param folder folder to zip 
      * @param zipOutputStream output stream. Usually a bytearray 
      * @throws IOException if any error occurs 
      */
    public static void createZip(File folder, OutputStream zipOutputStream) throws IOException {
        BufferedOutputStream bufferedOutputStream = null;
        ZipArchiveOutputStream zipArchiveOutputStream = null;
        try {
            bufferedOutputStream = new BufferedOutputStream(zipOutputStream);
            zipArchiveOutputStream = new ZipArchiveOutputStream(bufferedOutputStream);
            addFileToZip(zipArchiveOutputStream, folder);
        } finally {
            if (zipArchiveOutputStream != null) {
                zipArchiveOutputStream.finish();
                zipArchiveOutputStream.close();
            }
            if (bufferedOutputStream != null) {
                bufferedOutputStream.close();
            }
            if (zipOutputStream != null) {
                zipOutputStream.close();
            }
        }

    }

    /**
     * It calls at first time for main folder. 
     * 
     * @param zipArchiveOutputStream zip output stream 
     * @param path is relative path from main folder 
     * 
     * @throws IOException if any error occurs 
     */
    private static void addFileToZip(ZipArchiveOutputStream zipArchiveOutputStream, File file) throws IOException {
        addFileToZip(zipArchiveOutputStream, file, null);
    }

    /** 
     * Creates a zip entry for all files and/or directories of main folder 
     * 
     * @param zipArchiveOutputStream zip output stream 
     * @param file The file being added 
     * @param path is relative path from main folder 
     * 
     * @throws IOException if any error occurs 
     */
    private static void addFileToZip(ZipArchiveOutputStream zipArchiveOutputStream, File file, String path)
            throws IOException {
        // at first call it is the folder, otherwise is the relative path
        String entryName = (path != null) ? path + file.getName() : file.getName();
        ZipArchiveEntry zipEntry = new ZipArchiveEntry(file, entryName);
        zipArchiveOutputStream.putArchiveEntry(zipEntry);

        // if is a file, add the content to zip file
        if (file.isFile()) {
            FileInputStream fInputStream = null;
            try {
                fInputStream = new FileInputStream(file);
                IOUtils.copy(fInputStream, zipArchiveOutputStream);
                zipArchiveOutputStream.closeArchiveEntry();
            } finally {
                IOUtils.closeQuietly(fInputStream);
            }
        } else {
            // is a directory so it calls recursively all files in folder
            zipArchiveOutputStream.closeArchiveEntry();
            File[] children = file.listFiles();
            if (children != null) {
                for (File child : children) {
                    addFileToZip(zipArchiveOutputStream, child, entryName + "/");
                }
            }
        }
    }
}