/**
* Copyright (C) cedarsoft GmbH.
*
* Licensed under the GNU General Public License version 3 (the "License")
* with Classpath Exception; you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.cedarsoft.org/gpl3ce
* (GPL 3 with Classpath Exception)
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 3 only, as
* published by the Free Software Foundation. cedarsoft GmbH designates this
* particular file as subject to the "Classpath" exception as provided
* by cedarsoft GmbH in the LICENSE file that accompanied this code.
*
* This code 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
* version 3 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 3 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact cedarsoft GmbH, 72810 Gomaringen, Germany,
* or visit www.cedarsoft.com if you need additional information or
* have any questions.
*/
package com.cedarsoft.zip;
import org.apache.commons.compress.archivers.ArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveInputStream;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
/**
* Extracts ZIP files
*
* @author Johannes Schneider (<a href=mailto:js@cedarsoft.com>js@cedarsoft.com</a>)
*/
public class ZipExtractor {
private static final int BUFFER_LENGTH = 1024;
@Nullable
private final Condition condition;
/**
* <p>Constructor for ZipExtractor.</p>
*/
public ZipExtractor() {
this( null );
}
/**
* <p>Constructor for ZipExtractor.</p>
*
* @param condition a {@link ZipExtractor.Condition} object.
*/
public ZipExtractor( @Nullable Condition condition ) {
this.condition = condition;
}
/**
* Extract the zip file to the given destination
*
* @param destination the destination the file will be extracted to
* @param inputStream the input stream providing the zipped content
* @throws IOException if any.
*/
public void extract( @NotNull File destination, @NotNull final InputStream inputStream ) throws IOException {
if ( !destination.exists() || !destination.isDirectory() ) {
throw new IllegalArgumentException( "Invalid destination: " + destination.getCanonicalPath() );
}
ZipArchiveInputStream zipInputStream = new ZipArchiveInputStream( inputStream );
try {
byte[] buf = new byte[BUFFER_LENGTH];
for ( ArchiveEntry zipEntry = zipInputStream.getNextEntry(); zipEntry != null; zipEntry = zipInputStream.getNextEntry() ) {
if ( condition != null && !condition.shallExtract( zipEntry ) ) {
continue;
}
String entryName = zipEntry.getName();
File newFile = new File( destination, entryName );
//Is a directory
if ( zipEntry.isDirectory() ) {
newFile.mkdirs();
continue;
}
//Make the directory structure
newFile.getParentFile().mkdirs();
FileOutputStream fileoutputstream = new FileOutputStream( newFile );
try {
int n;
while ( ( n = zipInputStream.read( buf, 0, BUFFER_LENGTH ) ) > -1 ) {
fileoutputstream.write( buf, 0, n );
}
} finally {
fileoutputstream.close();
}
}
} finally {
zipInputStream.close();
}
}
/**
* Returns the currently set condition
*
* @return the condition
*/
@Nullable
public Condition getCondition() {
return condition;
}
/**
* A condition can decide whether a given zip entry shall be extracted or not
*/
public interface Condition {
/**
* Returns whether the given entry shall be extracted
*
* @param zipEntry the zip entry
* @return whether the entry shall be extracted
*/
boolean shallExtract( @NotNull ArchiveEntry zipEntry );
}
/**
* Inverts a condition
*/
public static class InvertedCondition implements Condition {
private final Condition condition;
/**
* Creates a new inverted condition
*
* @param condition the delegate that is inverted
*/
public InvertedCondition( @NotNull Condition condition ) {
this.condition = condition;
}
@Override
public boolean shallExtract( @NotNull ArchiveEntry zipEntry ) {
return !condition.shallExtract( zipEntry );
}
}
}