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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* 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.IOException;
import java.io.InputStream;
import java.nio.ByteOrder;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import libcore.io.BufferIterator;
import libcore.io.HeapBufferIterator;
import libcore.io.Streams;
/**
* An entry within a zip file.
* An entry has attributes such as its name (which is actually a path) and the uncompressed size
* of the corresponding data. An entry does not contain the data itself, but can be used as a key
* with {@link ZipFile#getInputStream}. The class documentation for {@link ZipInputStream} and
* {@link ZipOutputStream} shows how {@code ZipEntry} is used in conjunction with those two classes.
*/
public class ZipEntry implements ZipConstants, Cloneable {
String name;
String comment;
long crc = -1; // Needs to be a long to distinguish -1 ("not set") from the 0xffffffff CRC32.
long compressedSize = -1;
long size = -1;
int compressionMethod = -1;
int time = -1;
int modDate = -1;
byte[] extra;
int nameLength = -1;
long localHeaderRelOffset = -1;
long dataOffset = -1;
/**
* Zip entry state: Deflated.
*/
public static final int DEFLATED = 8;
/**
* Zip entry state: Stored.
*/
public static final int STORED = 0;
ZipEntry(String name, String comment, long crc, long compressedSize,
long size, int compressionMethod, int time, int modDate, byte[] extra,
int nameLength, long localHeaderRelOffset, long dataOffset) {
this.name = name;
this.comment = comment;
this.crc = crc;
this.compressedSize = compressedSize;
this.size = size;
this.compressionMethod = compressionMethod;
this.time = time;
this.modDate = modDate;
this.extra = extra;
this.nameLength = nameLength;
this.localHeaderRelOffset = localHeaderRelOffset;
this.dataOffset = dataOffset;
}
/**
* Constructs a new {@code ZipEntry} with the specified name. The name is actually a path,
* and may contain {@code /} characters.
*
* @throws IllegalArgumentException
* if the name length is outside the range (> 0xFFFF).
*/
public ZipEntry(String name) {
if (name == null) {
throw new NullPointerException("name == null");
}
validateStringLength("Name", name);
this.name = name;
}
/**
* Returns the comment for this {@code ZipEntry}, or {@code null} if there is no comment.
* If we're reading a zip file using {@code ZipInputStream}, the comment is not available.
*/
public String getComment() {
return comment;
}
/**
* Gets the compressed size of this {@code ZipEntry}.
*
* @return the compressed size, or -1 if the compressed size has not been
* set.
*/
public long getCompressedSize() {
return compressedSize;
}
/**
* Gets the checksum for this {@code ZipEntry}.
*
* @return the checksum, or -1 if the checksum has not been set.
*/
public long getCrc() {
return crc;
}
/**
* Gets the extra information for this {@code ZipEntry}.
*
* @return a byte array containing the extra information, or {@code null} if
* there is none.
*/
public byte[] getExtra() {
return extra;
}
/**
* Gets the compression method for this {@code ZipEntry}.
*
* @return the compression method, either {@code DEFLATED}, {@code STORED}
* or -1 if the compression method has not been set.
*/
public int getMethod() {
return compressionMethod;
}
/**
* Gets the name of this {@code ZipEntry}.
*
* @return the entry name.
*/
public String getName() {
return name;
}
/**
* Gets the uncompressed size of this {@code ZipEntry}.
*
* @return the uncompressed size, or {@code -1} if the size has not been
* set.
*/
public long getSize() {
return size;
}
/**
* Gets the last modification time of this {@code ZipEntry}.
*
* @return the last modification time as the number of milliseconds since
* Jan. 1, 1970.
*/
public long getTime() {
if (time != -1) {
GregorianCalendar cal = new GregorianCalendar();
cal.set(Calendar.MILLISECOND, 0);
cal.set(1980 + ((modDate >> 9) & 0x7f), ((modDate >> 5) & 0xf) - 1,
modDate & 0x1f, (time >> 11) & 0x1f, (time >> 5) & 0x3f,
(time & 0x1f) << 1);
return cal.getTime().getTime();
}
return -1;
}
/**
* Determine whether or not this {@code ZipEntry} is a directory.
*
* @return {@code true} when this {@code ZipEntry} is a directory, {@code
* false} otherwise.
*/
public boolean isDirectory() {
return name.charAt(name.length() - 1) == '/';
}
/**
* Sets the comment for this {@code ZipEntry}.
* @throws IllegalArgumentException if the comment is >= 64 Ki UTF-8 bytes.
*/
public void setComment(String comment) {
if (comment == null) {
this.comment = null;
return;
}
validateStringLength("Comment", comment);
this.comment = comment;
}
/**
* Sets the compressed size for this {@code ZipEntry}.
*
* @param value
* the compressed size (in bytes).
*/
public void setCompressedSize(long value) {
compressedSize = value;
}
/**
* Sets the checksum for this {@code ZipEntry}.
*
* @param value
* the checksum for this entry.
* @throws IllegalArgumentException
* if {@code value} is < 0 or > 0xFFFFFFFFL.
*/
public void setCrc(long value) {
if (value >= 0 && value <= 0xFFFFFFFFL) {
crc = value;
} else {
throw new IllegalArgumentException("Bad CRC32: " + value);
}
}
/**
* Sets the extra information for this {@code ZipEntry}.
*
* @throws IllegalArgumentException if the data length >= 64 KiB.
*/
public void setExtra(byte[] data) {
if (data != null && data.length > 0xffff) {
throw new IllegalArgumentException("Extra data too long: " + data.length);
}
extra = data;
}
/**
* Sets the compression method for this entry to either {@code DEFLATED} or {@code STORED}.
* The default is {@code DEFLATED}, which will cause the size, compressed size, and CRC to be
* set automatically, and the entry's data to be compressed. If you switch to {@code STORED}
* note that you'll have to set the size (or compressed size; they must be the same, but it's
* okay to only set one) and CRC yourself because they must appear before the user data
* in the resulting zip file. See {@link #setSize} and {@link #setCrc}.
* @throws IllegalArgumentException
* when value is not {@code DEFLATED} or {@code STORED}.
*/
public void setMethod(int value) {
if (value != STORED && value != DEFLATED) {
throw new IllegalArgumentException("Bad method: " + value);
}
compressionMethod = value;
}
/**
* Sets the uncompressed size of this {@code ZipEntry}.
*
* @param value
* the uncompressed size for this entry.
* @throws IllegalArgumentException
* if {@code value} < 0 or {@code value} > 0xFFFFFFFFL.
*/
public void setSize(long value) {
if (value >= 0 && value <= 0xFFFFFFFFL) {
size = value;
} else {
throw new IllegalArgumentException("Bad size: " + value);
}
}
/**
* Sets the modification time of this {@code ZipEntry}.
*
* @param value
* the modification time as the number of milliseconds since Jan.
* 1, 1970.
*/
public void setTime(long value) {
GregorianCalendar cal = new GregorianCalendar();
cal.setTime(new Date(value));
int year = cal.get(Calendar.YEAR);
if (year < 1980) {
modDate = 0x21;
time = 0;
} else {
modDate = cal.get(Calendar.DATE);
modDate = (cal.get(Calendar.MONTH) + 1 << 5) | modDate;
modDate = ((cal.get(Calendar.YEAR) - 1980) << 9) | modDate;
time = cal.get(Calendar.SECOND) >> 1;
time = (cal.get(Calendar.MINUTE) << 5) | time;
time = (cal.get(Calendar.HOUR_OF_DAY) << 11) | time;
}
}
/** @hide */
public void setDataOffset(long value) {
dataOffset = value;
}
/** @hide */
public long getDataOffset() {
return dataOffset;
}
/**
* Returns the string representation of this {@code ZipEntry}.
*
* @return the string representation of this {@code ZipEntry}.
*/
@Override
public String toString() {
return name;
}
/**
* Constructs a new {@code ZipEntry} using the values obtained from {@code
* ze}.
*
* @param ze
* the {@code ZipEntry} from which to obtain values.
*/
public ZipEntry(ZipEntry ze) {
name = ze.name;
comment = ze.comment;
time = ze.time;
size = ze.size;
compressedSize = ze.compressedSize;
crc = ze.crc;
compressionMethod = ze.compressionMethod;
modDate = ze.modDate;
extra = ze.extra;
nameLength = ze.nameLength;
localHeaderRelOffset = ze.localHeaderRelOffset;
dataOffset = ze.dataOffset;
}
/**
* Returns a deep copy of this zip entry.
*/
@Override public Object clone() {
try {
ZipEntry result = (ZipEntry) super.clone();
result.extra = extra != null ? extra.clone() : null;
return result;
} catch (CloneNotSupportedException e) {
throw new AssertionError(e);
}
}
/**
* Returns the hash code for this {@code ZipEntry}.
*
* @return the hash code of the entry.
*/
@Override
public int hashCode() {
return name.hashCode();
}
/*
* Internal constructor. Creates a new ZipEntry by reading the
* Central Directory Entry (CDE) from "in", which must be positioned
* at the CDE signature. If the GPBF_UTF8_FLAG is set in the CDE then
* UTF-8 is used to decode the string information, otherwise the
* defaultCharset is used.
*
* On exit, "in" will be positioned at the start of the next entry
* in the Central Directory.
*/
ZipEntry(byte[] cdeHdrBuf, InputStream cdStream, Charset defaultCharset) throws IOException {
Streams.readFully(cdStream, cdeHdrBuf, 0, cdeHdrBuf.length);
BufferIterator it = HeapBufferIterator.iterator(cdeHdrBuf, 0, cdeHdrBuf.length,
ByteOrder.LITTLE_ENDIAN);
int sig = it.readInt();
if (sig != CENSIG) {
ZipFile.throwZipException("Central Directory Entry", sig);
}
it.seek(8);
int gpbf = it.readShort() & 0xffff;
if ((gpbf & ZipFile.GPBF_UNSUPPORTED_MASK) != 0) {
throw new ZipException("Invalid General Purpose Bit Flag: " + gpbf);
}
// If the GPBF_UTF8_FLAG is set then the character encoding is UTF-8 whatever the default
// provided.
Charset charset = defaultCharset;
if ((gpbf & ZipFile.GPBF_UTF8_FLAG) != 0) {
charset = StandardCharsets.UTF_8;
}
compressionMethod = it.readShort() & 0xffff;
time = it.readShort() & 0xffff;
modDate = it.readShort() & 0xffff;
// These are 32-bit values in the file, but 64-bit fields in this object.
crc = ((long) it.readInt()) & 0xffffffffL;
compressedSize = ((long) it.readInt()) & 0xffffffffL;
size = ((long) it.readInt()) & 0xffffffffL;
nameLength = it.readShort() & 0xffff;
int extraLength = it.readShort() & 0xffff;
int commentByteCount = it.readShort() & 0xffff;
// This is a 32-bit value in the file, but a 64-bit field in this object.
it.seek(42);
localHeaderRelOffset = ((long) it.readInt()) & 0xffffffffL;
byte[] nameBytes = new byte[nameLength];
Streams.readFully(cdStream, nameBytes, 0, nameBytes.length);
if (containsNulByte(nameBytes)) {
throw new ZipException("Filename contains NUL byte: " + Arrays.toString(nameBytes));
}
name = new String(nameBytes, 0, nameBytes.length, charset);
if (extraLength > 0) {
extra = new byte[extraLength];
Streams.readFully(cdStream, extra, 0, extraLength);
}
if (commentByteCount > 0) {
byte[] commentBytes = new byte[commentByteCount];
Streams.readFully(cdStream, commentBytes, 0, commentByteCount);
comment = new String(commentBytes, 0, commentBytes.length, charset);
}
}
private static boolean containsNulByte(byte[] bytes) {
for (byte b : bytes) {
if (b == 0) {
return true;
}
}
return false;
}
private static void validateStringLength(String argument, String string) {
// This check is not perfect: the character encoding is determined when the entry is
// written out. UTF-8 is probably a worst-case: most alternatives should be single byte per
// character.
byte[] bytes = string.getBytes(StandardCharsets.UTF_8);
if (bytes.length > 0xffff) {
throw new IllegalArgumentException(argument + " too long: " + bytes.length);
}
}
}