/*
* @(#)ZipOutputStream.java 1.35 06/07/31
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.util.zip;
import java.io.OutputStream;
import java.io.IOException;
import java.util.Vector;
import java.util.HashSet;
/**
* This class implements an output stream filter for writing files in the
* ZIP file format. Includes support for both compressed and uncompressed
* entries.
*
* @author David Connelly
* @version 1.35, 07/31/06
*/
public
class ZipOutputStream extends DeflaterOutputStream implements ZipConstants {
private static class XEntry {
public final ZipEntry entry;
public final long offset;
public final int flag;
public XEntry(ZipEntry entry, long offset) {
this.entry = entry;
this.offset = offset;
this.flag = (entry.method == DEFLATED &&
(entry.size == -1 ||
entry.csize == -1 ||
entry.crc == -1))
// store size, compressed size, and crc-32 in data descriptor
// immediately following the compressed entry data
? 8
// store size, compressed size, and crc-32 in LOC header
: 0;
}
}
private XEntry current;
private Vector<XEntry> xentries = new Vector<XEntry>();
private HashSet<String> names = new HashSet<String>();
private CRC32 crc = new CRC32();
private long written = 0;
private long locoff = 0;
private String comment;
private int method = DEFLATED;
private boolean finished;
private boolean closed = false;
private static int version(ZipEntry e) throws ZipException {
switch (e.method) {
case DEFLATED: return 20;
case STORED: return 10;
default: throw new ZipException("unsupported compression method");
}
}
/**
* Checks to make sure that this stream has not been closed.
*/
private void ensureOpen() throws IOException {
if (closed) {
throw new IOException("Stream closed");
}
}
/**
* Compression method for uncompressed (STORED) entries.
*/
public static final int STORED = ZipEntry.STORED;
/**
* Compression method for compressed (DEFLATED) entries.
*/
public static final int DEFLATED = ZipEntry.DEFLATED;
/**
* Creates a new ZIP output stream.
* @param out the actual output stream
*/
public ZipOutputStream(OutputStream out) {
super(out, new Deflater(Deflater.DEFAULT_COMPRESSION, true));
usesDefaultDeflater = true;
}
/**
* Sets the ZIP file comment.
* @param comment the comment string
* @exception IllegalArgumentException if the length of the specified
* ZIP file comment is greater than 0xFFFF bytes
*/
public void setComment(String comment) {
if (comment != null && comment.length() > 0xffff/3
&& getUTF8Length(comment) > 0xffff) {
throw new IllegalArgumentException("ZIP file comment too long.");
}
this.comment = comment;
}
/**
* Sets the default compression method for subsequent entries. This
* default will be used whenever the compression method is not specified
* for an individual ZIP file entry, and is initially set to DEFLATED.
* @param method the default compression method
* @exception IllegalArgumentException if the specified compression method
* is invalid
*/
public void setMethod(int method) {
if (method != DEFLATED && method != STORED) {
throw new IllegalArgumentException("invalid compression method");
}
this.method = method;
}
/**
* Sets the compression level for subsequent entries which are DEFLATED.
* The default setting is DEFAULT_COMPRESSION.
* @param level the compression level (0-9)
* @exception IllegalArgumentException if the compression level is invalid
*/
public void setLevel(int level) {
def.setLevel(level);
}
/**
* Begins writing a new ZIP file entry and positions the stream to the
* start of the entry data. Closes the current entry if still active.
* The default compression method will be used if no compression method
* was specified for the entry, and the current time will be used if
* the entry has no set modification time.
* @param e the ZIP entry to be written
* @exception ZipException if a ZIP format error has occurred
* @exception IOException if an I/O error has occurred
*/
public void putNextEntry(ZipEntry e) throws IOException {
ensureOpen();
if (current != null) {
closeEntry(); // close previous entry
}
if (e.time == -1) {
e.setTime(System.currentTimeMillis());
}
if (e.method == -1) {
e.method = method; // use default method
}
switch (e.method) {
case DEFLATED:
break;
case STORED:
// compressed size, uncompressed size, and crc-32 must all be
// set for entries using STORED compression method
if (e.size == -1) {
e.size = e.csize;
} else if (e.csize == -1) {
e.csize = e.size;
} else if (e.size != e.csize) {
throw new ZipException(
"STORED entry where compressed != uncompressed size");
}
if (e.size == -1 || e.crc == -1) {
throw new ZipException(
"STORED entry missing size, compressed size, or crc-32");
}
break;
default:
throw new ZipException("unsupported compression method");
}
if (! names.add(e.name)) {
throw new ZipException("duplicate entry: " + e.name);
}
current = new XEntry(e, written);
xentries.add(current);
writeLOC(current);
}
/**
* Closes the current ZIP entry and positions the stream for writing
* the next entry.
* @exception ZipException if a ZIP format error has occurred
* @exception IOException if an I/O error has occurred
*/
public void closeEntry() throws IOException {
ensureOpen();
if (current != null) {
ZipEntry e = current.entry;
switch (e.method) {
case DEFLATED:
def.finish();
while (!def.finished()) {
deflate();
}
if ((current.flag & 8) == 0) {
// verify size, compressed size, and crc-32 settings
if (e.size != def.getBytesRead()) {
throw new ZipException(
"invalid entry size (expected " + e.size +
" but got " + def.getBytesRead() + " bytes)");
}
if (e.csize != def.getBytesWritten()) {
throw new ZipException(
"invalid entry compressed size (expected " +
e.csize + " but got " + def.getBytesWritten() + " bytes)");
}
if (e.crc != crc.getValue()) {
throw new ZipException(
"invalid entry CRC-32 (expected 0x" +
Long.toHexString(e.crc) + " but got 0x" +
Long.toHexString(crc.getValue()) + ")");
}
} else {
e.size = def.getBytesRead();
e.csize = def.getBytesWritten();
e.crc = crc.getValue();
writeEXT(e);
}
def.reset();
written += e.csize;
break;
case STORED:
// we already know that both e.size and e.csize are the same
if (e.size != written - locoff) {
throw new ZipException(
"invalid entry size (expected " + e.size +
" but got " + (written - locoff) + " bytes)");
}
if (e.crc != crc.getValue()) {
throw new ZipException(
"invalid entry crc-32 (expected 0x" +
Long.toHexString(e.crc) + " but got 0x" +
Long.toHexString(crc.getValue()) + ")");
}
break;
default:
throw new ZipException("invalid compression method");
}
crc.reset();
current = null;
}
}
/**
* Writes an array of bytes to the current ZIP entry data. This method
* will block until all the bytes are written.
* @param b the data to be written
* @param off the start offset in the data
* @param len the number of bytes that are written
* @exception ZipException if a ZIP file error has occurred
* @exception IOException if an I/O error has occurred
*/
public synchronized void write(byte[] b, int off, int len)
throws IOException
{
ensureOpen();
if (off < 0 || len < 0 || off > b.length - len) {
throw new IndexOutOfBoundsException();
} else if (len == 0) {
return;
}
if (current == null) {
throw new ZipException("no current ZIP entry");
}
ZipEntry entry = current.entry;
switch (entry.method) {
case DEFLATED:
super.write(b, off, len);
break;
case STORED:
written += len;
if (written - locoff > entry.size) {
throw new ZipException(
"attempt to write past end of STORED entry");
}
out.write(b, off, len);
break;
default:
throw new ZipException("invalid compression method");
}
crc.update(b, off, len);
}
/**
* Finishes writing the contents of the ZIP output stream without closing
* the underlying stream. Use this method when applying multiple filters
* in succession to the same output stream.
* @exception ZipException if a ZIP file error has occurred
* @exception IOException if an I/O exception has occurred
*/
public void finish() throws IOException {
ensureOpen();
if (finished) {
return;
}
if (current != null) {
closeEntry();
}
if (xentries.size() < 1) {
throw new ZipException("ZIP file must have at least one entry");
}
// write central directory
long off = written;
for (XEntry xentry : xentries)
writeCEN(xentry);
writeEND(off, written - off);
finished = true;
}
/**
* Closes the ZIP output stream as well as the stream being filtered.
* @exception ZipException if a ZIP file error has occurred
* @exception IOException if an I/O error has occurred
*/
public void close() throws IOException {
if (!closed) {
super.close();
closed = true;
}
}
/*
* Writes local file (LOC) header for specified entry.
*/
private void writeLOC(XEntry xentry) throws IOException {
ZipEntry e = xentry.entry;
int flag = xentry.flag;
writeInt(LOCSIG); // LOC header signature
writeShort(version(e)); // version needed to extract
writeShort(flag); // general purpose bit flag
writeShort(e.method); // compression method
writeInt(e.time); // last modification time
if ((flag & 8) == 8) {
// store size, uncompressed size, and crc-32 in data descriptor
// immediately following compressed entry data
writeInt(0);
writeInt(0);
writeInt(0);
} else {
writeInt(e.crc); // crc-32
writeInt(e.csize); // compressed size
writeInt(e.size); // uncompressed size
}
byte[] nameBytes = getUTF8Bytes(e.name);
writeShort(nameBytes.length);
writeShort(e.extra != null ? e.extra.length : 0);
writeBytes(nameBytes, 0, nameBytes.length);
if (e.extra != null) {
writeBytes(e.extra, 0, e.extra.length);
}
locoff = written;
}
/*
* Writes extra data descriptor (EXT) for specified entry.
*/
private void writeEXT(ZipEntry e) throws IOException {
writeInt(EXTSIG); // EXT header signature
writeInt(e.crc); // crc-32
writeInt(e.csize); // compressed size
writeInt(e.size); // uncompressed size
}
/*
* Write central directory (CEN) header for specified entry.
* REMIND: add support for file attributes
*/
private void writeCEN(XEntry xentry) throws IOException {
ZipEntry e = xentry.entry;
int flag = xentry.flag;
int version = version(e);
writeInt(CENSIG); // CEN header signature
writeShort(version); // version made by
writeShort(version); // version needed to extract
writeShort(flag); // general purpose bit flag
writeShort(e.method); // compression method
writeInt(e.time); // last modification time
writeInt(e.crc); // crc-32
writeInt(e.csize); // compressed size
writeInt(e.size); // uncompressed size
byte[] nameBytes = getUTF8Bytes(e.name);
writeShort(nameBytes.length);
writeShort(e.extra != null ? e.extra.length : 0);
byte[] commentBytes;
if (e.comment != null) {
commentBytes = getUTF8Bytes(e.comment);
writeShort(commentBytes.length);
} else {
commentBytes = null;
writeShort(0);
}
writeShort(0); // starting disk number
writeShort(0); // internal file attributes (unused)
writeInt(0); // external file attributes (unused)
writeInt(xentry.offset); // relative offset of local header
writeBytes(nameBytes, 0, nameBytes.length);
if (e.extra != null) {
writeBytes(e.extra, 0, e.extra.length);
}
if (commentBytes != null) {
writeBytes(commentBytes, 0, commentBytes.length);
}
}
/*
* Writes end of central directory (END) header.
*/
private void writeEND(long off, long len) throws IOException {
int count = xentries.size();
writeInt(ENDSIG); // END record signature
writeShort(0); // number of this disk
writeShort(0); // central directory start disk
writeShort(count); // number of directory entries on disk
writeShort(count); // total number of directory entries
writeInt(len); // length of central directory
writeInt(off); // offset of central directory
if (comment != null) { // zip file comment
byte[] b = getUTF8Bytes(comment);
writeShort(b.length);
writeBytes(b, 0, b.length);
} else {
writeShort(0);
}
}
/*
* Writes a 16-bit short to the output stream in little-endian byte order.
*/
private void writeShort(int v) throws IOException {
OutputStream out = this.out;
out.write((v >>> 0) & 0xff);
out.write((v >>> 8) & 0xff);
written += 2;
}
/*
* Writes a 32-bit int to the output stream in little-endian byte order.
*/
private void writeInt(long v) throws IOException {
OutputStream out = this.out;
out.write((int)((v >>> 0) & 0xff));
out.write((int)((v >>> 8) & 0xff));
out.write((int)((v >>> 16) & 0xff));
out.write((int)((v >>> 24) & 0xff));
written += 4;
}
/*
* Writes an array of bytes to the output stream.
*/
private void writeBytes(byte[] b, int off, int len) throws IOException {
super.out.write(b, off, len);
written += len;
}
/*
* Returns the length of String's UTF8 encoding.
*/
static int getUTF8Length(String s) {
int count = 0;
for (int i = 0; i < s.length(); i++) {
char ch = s.charAt(i);
if (ch <= 0x7f) {
count++;
} else if (ch <= 0x7ff) {
count += 2;
} else {
count += 3;
}
}
return count;
}
/*
* Returns an array of bytes representing the UTF8 encoding
* of the specified String.
*/
private static byte[] getUTF8Bytes(String s) {
char[] c = s.toCharArray();
int len = c.length;
// Count the number of encoded bytes...
int count = 0;
for (int i = 0; i < len; i++) {
int ch = c[i];
if (ch <= 0x7f) {
count++;
} else if (ch <= 0x7ff) {
count += 2;
} else {
count += 3;
}
}
// Now return the encoded bytes...
byte[] b = new byte[count];
int off = 0;
for (int i = 0; i < len; i++) {
int ch = c[i];
if (ch <= 0x7f) {
b[off++] = (byte)ch;
} else if (ch <= 0x7ff) {
b[off++] = (byte)((ch >> 6) | 0xc0);
b[off++] = (byte)((ch & 0x3f) | 0x80);
} else {
b[off++] = (byte)((ch >> 12) | 0xe0);
b[off++] = (byte)(((ch >> 6) & 0x3f) | 0x80);
b[off++] = (byte)((ch & 0x3f) | 0x80);
}
}
return b;
}
}
|
