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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package java.util.zip;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.HashSet;
import libcore.util.EmptyArray;

/**
 * Used to write (compress) data into zip files.
 *
 * 

{@code ZipOutputStream} is used to write {@link ZipEntry}s to the underlying * stream. Output from {@code ZipOutputStream} can be read using {@link ZipFile} * or {@link ZipInputStream}. * *

While {@code DeflaterOutputStream} can write compressed zip file * entries, this extension can write uncompressed entries as well. * Use {@link ZipEntry#setMethod} or {@link #setMethod} with the {@link ZipEntry#STORED} flag. * *

Example

*

Using {@code ZipOutputStream} is a little more complicated than {@link GZIPOutputStream} * because zip files are containers that can contain multiple files. This code creates a zip * file containing several files, similar to the {@code zip(1)} utility. *

 * OutputStream os = ...
 * ZipOutputStream zos = new ZipOutputStream(new BufferedOutputStream(os));
 * try {
 *     for (int i = 0; i < fileCount; ++i) {
 *         String filename = ...
 *         byte[] bytes = ...
 *         ZipEntry entry = new ZipEntry(filename);
 *         zos.putNextEntry(entry);
 *         zos.write(bytes);
 *         zos.closeEntry();
 *     }
 * } finally {
 *     zos.close();
 * }
 * 
*/ public class ZipOutputStream extends DeflaterOutputStream implements ZipConstants { /** * Indicates deflated entries. */ public static final int DEFLATED = 8; /** * Indicates uncompressed entries. */ public static final int STORED = 0; private static final int ZIP_VERSION_2_0 = 20; // Zip specification version 2.0. private byte[] commentBytes = EmptyArray.BYTE; private final HashSet entries = new HashSet(); private int defaultCompressionMethod = DEFLATED; private int compressionLevel = Deflater.DEFAULT_COMPRESSION; private ByteArrayOutputStream cDir = new ByteArrayOutputStream(); private ZipEntry currentEntry; private final CRC32 crc = new CRC32(); private int offset = 0, curOffset = 0, nameLength; private byte[] nameBytes; /** * Constructs a new {@code ZipOutputStream} that writes a zip file * to the given {@code OutputStream}. */ public ZipOutputStream(OutputStream os) { super(os, new Deflater(Deflater.DEFAULT_COMPRESSION, true)); } /** * Closes the current {@code ZipEntry}, if any, and the underlying output * stream. If the stream is already closed this method does nothing. * * @throws IOException * If an error occurs closing the stream. */ @Override public void close() throws IOException { // don't call super.close() because that calls finish() conditionally if (out != null) { finish(); def.end(); out.close(); out = null; } } /** * Closes the current {@code ZipEntry}. Any entry terminal data is written * to the underlying stream. * * @throws IOException * If an error occurs closing the entry. */ public void closeEntry() throws IOException { checkOpen(); if (currentEntry == null) { return; } if (currentEntry.getMethod() == DEFLATED) { super.finish(); } // Verify values for STORED types if (currentEntry.getMethod() == STORED) { if (crc.getValue() != currentEntry.crc) { throw new ZipException("CRC mismatch"); } if (currentEntry.size != crc.tbytes) { throw new ZipException("Size mismatch"); } } curOffset = LOCHDR; // Write the DataDescriptor if (currentEntry.getMethod() != STORED) { curOffset += EXTHDR; writeLong(out, EXTSIG); writeLong(out, currentEntry.crc = crc.getValue()); writeLong(out, currentEntry.compressedSize = def.getTotalOut()); writeLong(out, currentEntry.size = def.getTotalIn()); } // Update the CentralDirectory // http://www.pkware.com/documents/casestudies/APPNOTE.TXT int flags = currentEntry.getMethod() == STORED ? 0 : ZipFile.GPBF_DATA_DESCRIPTOR_FLAG; // Since gingerbread, we always set the UTF-8 flag on individual files. // Some tools insist that the central directory also have the UTF-8 flag. // http://code.google.com/p/android/issues/detail?id=20214 flags |= ZipFile.GPBF_UTF8_FLAG; writeLong(cDir, CENSIG); writeShort(cDir, ZIP_VERSION_2_0); // Version this file was made by. writeShort(cDir, ZIP_VERSION_2_0); // Minimum version needed to extract. writeShort(cDir, flags); writeShort(cDir, currentEntry.getMethod()); writeShort(cDir, currentEntry.time); writeShort(cDir, currentEntry.modDate); writeLong(cDir, crc.getValue()); if (currentEntry.getMethod() == DEFLATED) { curOffset += writeLong(cDir, def.getTotalOut()); writeLong(cDir, def.getTotalIn()); } else { curOffset += writeLong(cDir, crc.tbytes); writeLong(cDir, crc.tbytes); } curOffset += writeShort(cDir, nameLength); if (currentEntry.extra != null) { curOffset += writeShort(cDir, currentEntry.extra.length); } else { writeShort(cDir, 0); } String comment = currentEntry.getComment(); byte[] commentBytes = EmptyArray.BYTE; if (comment != null) { commentBytes = comment.getBytes(StandardCharsets.UTF_8); } writeShort(cDir, commentBytes.length); // Comment length. writeShort(cDir, 0); // Disk Start writeShort(cDir, 0); // Internal File Attributes writeLong(cDir, 0); // External File Attributes writeLong(cDir, offset); cDir.write(nameBytes); nameBytes = null; if (currentEntry.extra != null) { cDir.write(currentEntry.extra); } offset += curOffset; if (commentBytes.length > 0) { cDir.write(commentBytes); } currentEntry = null; crc.reset(); def.reset(); done = false; } /** * Indicates that all entries have been written to the stream. Any terminal * information is written to the underlying stream. * * @throws IOException * if an error occurs while terminating the stream. */ @Override public void finish() throws IOException { // TODO: is there a bug here? why not checkOpen? if (out == null) { throw new IOException("Stream is closed"); } if (cDir == null) { return; } if (entries.isEmpty()) { throw new ZipException("No entries"); } if (currentEntry != null) { closeEntry(); } int cdirSize = cDir.size(); // Write Central Dir End writeLong(cDir, ENDSIG); writeShort(cDir, 0); // Disk Number writeShort(cDir, 0); // Start Disk writeShort(cDir, entries.size()); // Number of entries writeShort(cDir, entries.size()); // Number of entries writeLong(cDir, cdirSize); // Size of central dir writeLong(cDir, offset); // Offset of central dir writeShort(cDir, commentBytes.length); if (commentBytes.length > 0) { cDir.write(commentBytes); } // Write the central directory. cDir.writeTo(out); cDir = null; } /** * Writes entry information to the underlying stream. Data associated with * the entry can then be written using {@code write()}. After data is * written {@code closeEntry()} must be called to complete the writing of * the entry to the underlying stream. * * @param ze * the {@code ZipEntry} to store. * @throws IOException * If an error occurs storing the entry. * @see #write */ public void putNextEntry(ZipEntry ze) throws IOException { if (currentEntry != null) { closeEntry(); } // Did this ZipEntry specify a method, or should we use the default? int method = ze.getMethod(); if (method == -1) { method = defaultCompressionMethod; } // If the method is STORED, check that the ZipEntry was configured appropriately. if (method == STORED) { if (ze.getCompressedSize() == -1) { ze.setCompressedSize(ze.getSize()); } else if (ze.getSize() == -1) { ze.setSize(ze.getCompressedSize()); } if (ze.getCrc() == -1) { throw new ZipException("STORED entry missing CRC"); } if (ze.getSize() == -1) { throw new ZipException("STORED entry missing size"); } if (ze.size != ze.compressedSize) { throw new ZipException("STORED entry size/compressed size mismatch"); } } checkOpen(); if (entries.contains(ze.name)) { throw new ZipException("Entry already exists: " + ze.name); } if (entries.size() == 64*1024-1) { // TODO: support Zip64. throw new ZipException("Too many entries for the zip file format's 16-bit entry count"); } nameBytes = ze.name.getBytes(StandardCharsets.UTF_8); nameLength = nameBytes.length; if (nameLength > 0xffff) { throw new IllegalArgumentException("Name too long: " + nameLength + " UTF-8 bytes"); } def.setLevel(compressionLevel); ze.setMethod(method); currentEntry = ze; entries.add(currentEntry.name); // Local file header. // http://www.pkware.com/documents/casestudies/APPNOTE.TXT int flags = (method == STORED) ? 0 : ZipFile.GPBF_DATA_DESCRIPTOR_FLAG; // Java always outputs UTF-8 filenames. (Before Java 7, the RI didn't set this flag and used // modified UTF-8. From Java 7, it sets this flag and uses normal UTF-8.) flags |= ZipFile.GPBF_UTF8_FLAG; writeLong(out, LOCSIG); // Entry header writeShort(out, ZIP_VERSION_2_0); // Minimum version needed to extract. writeShort(out, flags); writeShort(out, method); if (currentEntry.getTime() == -1) { currentEntry.setTime(System.currentTimeMillis()); } writeShort(out, currentEntry.time); writeShort(out, currentEntry.modDate); if (method == STORED) { writeLong(out, currentEntry.crc); writeLong(out, currentEntry.size); writeLong(out, currentEntry.size); } else { writeLong(out, 0); writeLong(out, 0); writeLong(out, 0); } writeShort(out, nameLength); if (currentEntry.extra != null) { writeShort(out, currentEntry.extra.length); } else { writeShort(out, 0); } out.write(nameBytes); if (currentEntry.extra != null) { out.write(currentEntry.extra); } } /** * Sets the comment associated with the file being written. See {@link ZipFile#getComment}. * @throws IllegalArgumentException if the comment is >= 64 Ki UTF-8 bytes. */ public void setComment(String comment) { if (comment == null) { this.commentBytes = null; return; } byte[] newCommentBytes = comment.getBytes(StandardCharsets.UTF_8); if (newCommentBytes.length > 0xffff) { throw new IllegalArgumentException("Comment too long: " + newCommentBytes.length + " bytes"); } this.commentBytes = newCommentBytes; } /** * Sets the compression level to be used * for writing entry data. */ public void setLevel(int level) { if (level < Deflater.DEFAULT_COMPRESSION || level > Deflater.BEST_COMPRESSION) { throw new IllegalArgumentException("Bad level: " + level); } compressionLevel = level; } /** * Sets the default compression method to be used when a {@code ZipEntry} doesn't * explicitly specify a method. See {@link ZipEntry#setMethod} for more details. */ public void setMethod(int method) { if (method != STORED && method != DEFLATED) { throw new IllegalArgumentException("Bad method: " + method); } defaultCompressionMethod = method; } private long writeLong(OutputStream os, long i) throws IOException { // Write out the long value as an unsigned int os.write((int) (i & 0xFF)); os.write((int) (i >> 8) & 0xFF); os.write((int) (i >> 16) & 0xFF); os.write((int) (i >> 24) & 0xFF); return i; } private int writeShort(OutputStream os, int i) throws IOException { os.write(i & 0xFF); os.write((i >> 8) & 0xFF); return i; } /** * Writes data for the current entry to the underlying stream. * * @exception IOException * If an error occurs writing to the stream */ @Override public void write(byte[] buffer, int offset, int byteCount) throws IOException { Arrays.checkOffsetAndCount(buffer.length, offset, byteCount); if (currentEntry == null) { throw new ZipException("No active entry"); } if (currentEntry.getMethod() == STORED) { out.write(buffer, offset, byteCount); } else { super.write(buffer, offset, byteCount); } crc.update(buffer, offset, byteCount); } private void checkOpen() throws IOException { if (cDir == null) { throw new IOException("Stream is closed"); } } }




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