ZipFile.java
/*
* Copyright (C) 2016 essobedo.
*
* This 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; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package com.github.essobedo.appma.core.zip;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
/**
* The class allowing to unzip a given zip file.
*
* @author Nicolas Filotto (nicolas.filotto@gmail.com)
* @version $Id$
* @since 1.0
*/
public final class ZipFile {
/**
* The zip file to unzip.
*/
private final File file;
/**
* Constructs a {@code ZipFile} with the specified file.
* @param file the zip file to unzip.
*/
public ZipFile(final File file) {
this.file = file;
}
/**
* Extracts the content of the zip file into the specified folder. The folder will be
* created automatically if it does not exist.
* @param destDir the destination folder.
* @throws IOException In case the file could not be unzipped.
*/
public void unzip(final File destDir) throws IOException {
if (!destDir.exists() && !destDir.mkdir()) {
throw new IOException(String.format("Could not create the destination directory '%s'",
destDir.getAbsolutePath()));
}
try (final ZipInputStream zipIn = new ZipInputStream(new FileInputStream(this.file))) {
ZipEntry entry = zipIn.getNextEntry();
// iterates over entries in the zip file
while (entry != null) {
final File file = new File(destDir, entry.getName());
if (entry.isDirectory()) {
// if the entry is a directory, make the directory
if (!file.mkdir()) {
throw new IOException(String.format("Could not create the sub-directory '%s'",
file.getAbsolutePath()));
}
} else {
// if the entry is a file, extracts it
ZipFile.extractFile(zipIn, file);
}
zipIn.closeEntry();
entry = zipIn.getNextEntry();
}
}
}
/**
* Extracts a zip entry (file entry).
* @param zipIn the zip entry to extract.
* @param file the destination file
* @throws IOException In case the zip entry could not be extracted.
*/
private static void extractFile(final ZipInputStream zipIn, final File file) throws IOException {
final byte[] bytesIn = new byte[1024];
try (final BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(file))) {
int read;
while ((read = zipIn.read(bytesIn)) != -1) {
bos.write(bytesIn, 0, read);
}
}
}
}