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/*
* Copyright (C) 2005-2015 Schlichtherle IT Services.
* All rights reserved. Use is subject to license terms.
*/
package net.java.truevfs.comp.zip;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.nio.channels.SeekableByteChannel;
import java.nio.charset.Charset;
import static java.nio.file.Files.newByteChannel;
import java.nio.file.Path;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import java.util.zip.ZipException;
import javax.annotation.CheckForNull;
import javax.annotation.Nullable;
import javax.annotation.concurrent.ThreadSafe;
import net.java.truecommons.io.AbstractSource;
import net.java.truecommons.io.LockInputStream;
import net.java.truecommons.io.OneTimeSource;
/**
* Replacement for {@link java.util.zip.ZipFile java.util.zip.ZipFile}.
*
* Where the constructors of this class accept a {@code charset}
* parameter, this is used to decode comments and entry names in the ZIP file.
* However, if an entry has bit 11 set in its General Purpose Bit Flag,
* then this parameter is ignored and "UTF-8" is used for this entry.
* This is in accordance to Appendix D of PKWARE's ZIP File Format
* Specification, version 6.3.0 and later.
*
* This class is able to skip a preamble like the one found in self extracting
* archives.
*
* Note that the entries returned by this class are instances of
* {@code net.truevfs.kernel.io.zip.ZipEntry} instead of
* {@code java.util.zip.ZipEntry}.
*
* @see ZipOutputStream
* @author Christian Schlichtherle
*/
@ThreadSafe
public class ZipFile extends AbstractZipFile {
/** The lock on which this object synchronizes. */
private final Lock lock = new ReentrantLock();
private final String name;
private volatile @CheckForNull ZipCryptoParameters cryptoParameters;
/**
* Equivalent to {@link #ZipFile(Path, Charset, boolean, boolean)
* ZipFile(file, DEFAULT_CHARSET, true, false)}
*/
public ZipFile(Path file)
throws IOException {
this(file, DEFAULT_CHARSET, true, false);
}
/**
* Equivalent to {@link #ZipFile(Path, Charset, boolean, boolean)
* ZipFile(file, charset, true, false)}
*/
public ZipFile(Path file, Charset charset)
throws IOException {
this(file, charset, true, false);
}
/**
* Opens the given {@code file} for reading its entries.
*
* @param file the file.
* @param charset the charset to use for decoding entry names and ZIP file
* comment.
* @param preambled if this is {@code true}, then the ZIP file may have a
* preamble.
* Otherwise, the ZIP file must start with either a Local File
* Header (LFH) signature or an End Of Central Directory (EOCD)
* Header, causing this constructor to fail if the file is actually
* a false positive ZIP file, i.e. not compatible to the ZIP File
* Format Specification.
* This may be useful to read Self Extracting ZIP files (SFX),
* which usually contain the application code required for
* extraction in the preamble.
* @param postambled if this is {@code true}, then the ZIP file may have a
* postamble of arbitrary length.
* Otherwise, the ZIP file must not have a postamble which exceeds
* 64KB size, including the End Of Central Directory record
* (i.e. including the ZIP file comment), causing this constructor
* to fail if the file is actually a false positive ZIP file, i.e.
* not compatible to the ZIP File Format Specification.
* This may be useful to read Self Extracting ZIP files (SFX) with
* large postambles.
* @throws ZipException if the file data is not compatible with the ZIP
* File Format Specification.
* @throws EOFException on unexpected end-of-file.
* @throws IOException on any I/O error.
* @see #recoverLostEntries()
*/
public ZipFile(
final Path file,
final Charset charset,
final boolean preambled,
final boolean postambled)
throws ZipException, EOFException, IOException {
super( new ZipSource(file),
new DefaultZipFileParameters(charset, preambled, postambled));
this.name = file.toString();
}
/**
* Equivalent to {@link #ZipFile(SeekableByteChannel, Charset, boolean, boolean)
* ZipFile(rof, DEFAULT_CHARSET, true, false)}
*/
public ZipFile(SeekableByteChannel channel)
throws IOException {
this(channel, DEFAULT_CHARSET, true, false);
}
/**
* Equivalent to {@link #ZipFile(SeekableByteChannel, Charset, boolean, boolean)
* ZipFile(rof, charset, true, false)}
*/
public ZipFile(SeekableByteChannel channel, Charset charset)
throws IOException {
this(channel, charset, true, false);
}
/**
* Opens the given {@link SeekableByteChannel} for reading its entries.
*
* @param channel the channel to read.
* @param charset the charset to use for decoding entry names and ZIP file
* comment.
* @param preambled if this is {@code true}, then the ZIP file may have a
* preamble.
* Otherwise, the ZIP file must start with either a Local File
* Header (LFH) signature or an End Of Central Directory (EOCD)
* Header, causing this constructor to fail if the file is actually
* a false positive ZIP file, i.e. not compatible to the ZIP File
* Format Specification.
* This may be useful to read Self Extracting ZIP files (SFX),
* which usually contain the application code required for
* extraction in the preamble.
* @param postambled if this is {@code true}, then the ZIP file may have a
* postamble of arbitrary length.
* Otherwise, the ZIP file must not have a postamble which exceeds
* 64KB size, including the End Of Central Directory record
* (i.e. including the ZIP file comment), causing this constructor
* to fail if the file is actually a false positive ZIP file, i.e.
* not compatible to the ZIP File Format Specification.
* This may be useful to read Self Extracting ZIP files (SFX) with
* large postambles.
* @throws ZipException if the channel data is not compatible with the ZIP
* File Format Specification.
* @throws EOFException on unexpected end-of-file.
* @throws IOException on any I/O error.
* @see #recoverLostEntries()
*/
public ZipFile(
SeekableByteChannel channel,
Charset charset,
boolean preambled,
boolean postambled)
throws ZipException, EOFException, IOException {
super( new OneTimeSource(channel),
new DefaultZipFileParameters(charset, preambled, postambled));
this.name = channel.toString();
}
/**
* {@inheritDoc}
*
* Note that this method is not thread-safe!
*/
@Override
public ZipFile recoverLostEntries() throws IOException {
super.recoverLostEntries();
return this;
}
/**
* Returns the {@link Object#toString() string representation} of whatever
* input source object was used to construct this ZIP file.
* For {@link String} and {@link Path} objects, this is a path name.
*/
public String getName() {
return name;
}
/**
* Enumerates clones of all entries in this ZIP file.
*
* @see #iterator()
*/
public Enumeration entries() {
final class CloneEnumeration implements Enumeration {
final Iterator i = ZipFile.super.iterator();
@Override
public boolean hasMoreElements() {
return i.hasNext();
}
@Override
public ZipEntry nextElement() {
return i.next().clone();
}
} // CloneEnumeration
return new CloneEnumeration();
}
/**
* Iterates through clones for all entries in this ZIP file.
* The iteration does not support element removal.
*/
@Override
public Iterator iterator() {
final class EntryIterator implements Iterator {
final Iterator i = ZipFile.super.iterator();
@Override
public boolean hasNext() {
return i.hasNext();
}
@Override
public ZipEntry next() {
return i.next().clone();
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
} // EntryIterator
return new EntryIterator();
}
/**
* Returns a clone of the entry for the given {@code name} or {@code null}
* if no entry with this name exists in this ZIP file.
*
* @param name the name of the ZIP entry.
* @return A clone of the entry for the given {@code name} or {@code null}
* if no entry with this name exists in this ZIP file.
*/
@Override
public ZipEntry entry(String name) {
final ZipEntry ze = super.entry(name);
return ze != null ? ze.clone() : null;
}
@Override
@SuppressWarnings("deprecation")
public InputStream getPreambleInputStream() throws IOException {
final InputStream in;
lock.lock();
try {
in = super.getPreambleInputStream();
} finally {
lock.unlock();
}
return new LockInputStream(lock, in);
}
@Override
@SuppressWarnings("deprecation")
public InputStream getPostambleInputStream() throws IOException {
final InputStream in;
lock.lock();
try {
in = super.getPostambleInputStream();
} finally {
lock.unlock();
}
return new LockInputStream(lock, in);
}
@Override
public boolean busy() {
lock.lock();
try {
return super.busy();
} finally {
lock.unlock();
}
}
@Override
public @Nullable ZipCryptoParameters getCryptoParameters() {
return cryptoParameters;
}
/**
* Sets the parameters for encryption or authentication of entries.
*
* @param cryptoParameters the parameters for encryption or authentication
* of entries.
*/
public void setCryptoParameters(
final @CheckForNull ZipCryptoParameters cryptoParameters) {
this.cryptoParameters = cryptoParameters;
}
@Override
@SuppressWarnings("deprecation")
protected InputStream getInputStream(
String name, Boolean check, boolean process)
throws IOException {
final InputStream in;
lock.lock();
try {
in = super.getInputStream(name, check, process);
} finally {
lock.unlock();
}
return in == null ? null : new LockInputStream(lock, in);
}
@Override
public void close() throws IOException {
lock.lock();
try {
super.close();
} finally {
lock.unlock();
}
}
/**
* A pool which allocates {@link SeekableByteChannel} objects for the
* file provided to its constructor.
*/
private static final class ZipSource extends AbstractSource {
final Path file;
ZipSource(final Path file) {
this.file = file;
}
@Override
public SeekableByteChannel channel() throws IOException {
return newByteChannel(file);
}
} // ZipSource
}