Java tutorial
/* * Copyright (c) 1995, 2017, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle 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 2 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 * 2 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.util.zip; import static java.util.zip.ZipUtils.*; import java.nio.file.attribute.FileTime; import java.util.Objects; import java.util.concurrent.TimeUnit; import java.time.LocalDateTime; import java.time.ZonedDateTime; import java.time.ZoneId; import static java.util.zip.ZipConstants64.*; /** * This class is used to represent a ZIP file entry. * * @author David Connelly * @since 1.1 */ public class ZipEntry implements ZipConstants, Cloneable { String name; // entry name long xdostime = -1; // last modification time (in extended DOS time, // where milliseconds lost in conversion might // be encoded into the upper half) FileTime mtime; // last modification time, from extra field data FileTime atime; // last access time, from extra field data FileTime ctime; // creation time, from extra field data long crc = -1; // crc-32 of entry data long size = -1; // uncompressed size of entry data long csize = -1; // compressed size of entry data int method = -1; // compression method int flag = 0; // general purpose flag byte[] extra; // optional extra field data for entry String comment; // optional comment string for entry /** * Compression method for uncompressed entries. */ public static final int STORED = 0; /** * Compression method for compressed (deflated) entries. */ public static final int DEFLATED = 8; /** * DOS time constant for representing timestamps before 1980. */ static final long DOSTIME_BEFORE_1980 = (1 << 21) | (1 << 16); /** * Approximately 128 years, in milliseconds (ignoring leap years etc). * * This establish an approximate high-bound value for DOS times in * milliseconds since epoch, used to enable an efficient but * sufficient bounds check to avoid generating extended last modified * time entries. * * Calculating the exact number is locale dependent, would require loading * TimeZone data eagerly, and would make little practical sense. Since DOS * times theoretically go to 2107 - with compatibility not guaranteed * after 2099 - setting this to a time that is before but near 2099 * should be sufficient. */ private static final long UPPER_DOSTIME_BOUND = 128L * 365 * 24 * 60 * 60 * 1000; /** * Creates a new zip entry with the specified name. * * @param name * The entry name * * @throws NullPointerException if the entry name is null * @throws IllegalArgumentException if the entry name is longer than * 0xFFFF bytes */ public ZipEntry(String name) { Objects.requireNonNull(name, "name"); if (name.length() > 0xFFFF) { throw new IllegalArgumentException("entry name too long"); } this.name = name; } /** * Creates a new zip entry with fields taken from the specified * zip entry. * * @param e * A zip Entry object * * @throws NullPointerException if the entry object is null */ public ZipEntry(ZipEntry e) { Objects.requireNonNull(e, "entry"); name = e.name; xdostime = e.xdostime; mtime = e.mtime; atime = e.atime; ctime = e.ctime; crc = e.crc; size = e.size; csize = e.csize; method = e.method; flag = e.flag; extra = e.extra; comment = e.comment; } /** * Creates a new un-initialized zip entry */ ZipEntry() { } /** * Returns the name of the entry. * @return the name of the entry */ public String getName() { return name; } /** * Sets the last modification time of the entry. * * <p> If the entry is output to a ZIP file or ZIP file formatted * output stream the last modification time set by this method will * be stored into the {@code date and time fields} of the zip file * entry and encoded in standard {@code MS-DOS date and time format}. * The {@link java.util.TimeZone#getDefault() default TimeZone} is * used to convert the epoch time to the MS-DOS data and time. * * @param time * The last modification time of the entry in milliseconds * since the epoch * * @see #getTime() * @see #getLastModifiedTime() */ public void setTime(long time) { this.xdostime = javaToExtendedDosTime(time); // Avoid setting the mtime field if time is in the valid // range for a DOS time if (xdostime != DOSTIME_BEFORE_1980 && time <= UPPER_DOSTIME_BOUND) { this.mtime = null; } else { this.mtime = FileTime.from(time, TimeUnit.MILLISECONDS); } } /** * Returns the last modification time of the entry. * * <p> If the entry is read from a ZIP file or ZIP file formatted * input stream, this is the last modification time from the {@code * date and time fields} of the zip file entry. The * {@link java.util.TimeZone#getDefault() default TimeZone} is used * to convert the standard MS-DOS formatted date and time to the * epoch time. * * @return The last modification time of the entry in milliseconds * since the epoch, or -1 if not specified * * @see #setTime(long) * @see #setLastModifiedTime(FileTime) */ public long getTime() { if (mtime != null) { return mtime.toMillis(); } return (xdostime != -1) ? extendedDosToJavaTime(xdostime) : -1; } /** * Sets the last modification time of the entry in local date-time. * * <p> If the entry is output to a ZIP file or ZIP file formatted * output stream the last modification time set by this method will * be stored into the {@code date and time fields} of the zip file * entry and encoded in standard {@code MS-DOS date and time format}. * If the date-time set is out of the range of the standard {@code * MS-DOS date and time format}, the time will also be stored into * zip file entry's extended timestamp fields in {@code optional * extra data} in UTC time. The {@link java.time.ZoneId#systemDefault() * system default TimeZone} is used to convert the local date-time * to UTC time. * * <p> {@code LocalDateTime} uses a precision of nanoseconds, whereas * this class uses a precision of milliseconds. The conversion will * truncate any excess precision information as though the amount in * nanoseconds was subject to integer division by one million. * * @param time * The last modification time of the entry in local date-time * * @see #getTimeLocal() * @since 9 */ public void setTimeLocal(LocalDateTime time) { int year = time.getYear() - 1980; if (year < 0) { this.xdostime = DOSTIME_BEFORE_1980; } else { this.xdostime = ((year << 25 | time.getMonthValue() << 21 | time.getDayOfMonth() << 16 | time.getHour() << 11 | time.getMinute() << 5 | time.getSecond() >> 1) & 0xffffffffL) + ((long) (((time.getSecond() & 0x1) * 1000) + time.getNano() / 1000_000) << 32); } if (xdostime != DOSTIME_BEFORE_1980 && year <= 0x7f) { this.mtime = null; } else { this.mtime = FileTime.from(ZonedDateTime.of(time, ZoneId.systemDefault()).toInstant()); } } /** * Returns the last modification time of the entry in local date-time. * * <p> If the entry is read from a ZIP file or ZIP file formatted * input stream, this is the last modification time from the zip * file entry's {@code optional extra data} if the extended timestamp * fields are present. Otherwise, the last modification time is read * from entry's standard MS-DOS formatted {@code date and time fields}. * * <p> The {@link java.time.ZoneId#systemDefault() system default TimeZone} * is used to convert the UTC time to local date-time. * * @return The last modification time of the entry in local date-time * * @see #setTimeLocal(LocalDateTime) * @since 9 */ public LocalDateTime getTimeLocal() { if (mtime != null) { return LocalDateTime.ofInstant(mtime.toInstant(), ZoneId.systemDefault()); } int ms = (int) (xdostime >> 32); return LocalDateTime.of((int) (((xdostime >> 25) & 0x7f) + 1980), (int) ((xdostime >> 21) & 0x0f), (int) ((xdostime >> 16) & 0x1f), (int) ((xdostime >> 11) & 0x1f), (int) ((xdostime >> 5) & 0x3f), (int) ((xdostime << 1) & 0x3e) + ms / 1000, (ms % 1000) * 1000_000); } /** * Sets the last modification time of the entry. * * <p> When output to a ZIP file or ZIP file formatted output stream * the last modification time set by this method will be stored into * zip file entry's {@code date and time fields} in {@code standard * MS-DOS date and time format}), and the extended timestamp fields * in {@code optional extra data} in UTC time. * * @param time * The last modification time of the entry * @return This zip entry * * @throws NullPointerException if the {@code time} is null * * @see #getLastModifiedTime() * @since 1.8 */ public ZipEntry setLastModifiedTime(FileTime time) { this.mtime = Objects.requireNonNull(time, "lastModifiedTime"); this.xdostime = javaToExtendedDosTime(time.to(TimeUnit.MILLISECONDS)); return this; } /** * Returns the last modification time of the entry. * * <p> If the entry is read from a ZIP file or ZIP file formatted * input stream, this is the last modification time from the zip * file entry's {@code optional extra data} if the extended timestamp * fields are present. Otherwise the last modification time is read * from the entry's {@code date and time fields}, the {@link * java.util.TimeZone#getDefault() default TimeZone} is used to convert * the standard MS-DOS formatted date and time to the epoch time. * * @return The last modification time of the entry, null if not specified * * @see #setLastModifiedTime(FileTime) * @since 1.8 */ public FileTime getLastModifiedTime() { if (mtime != null) return mtime; if (xdostime == -1) return null; return FileTime.from(getTime(), TimeUnit.MILLISECONDS); } /** * Sets the last access time of the entry. * * <p> If set, the last access time will be stored into the extended * timestamp fields of entry's {@code optional extra data}, when output * to a ZIP file or ZIP file formatted stream. * * @param time * The last access time of the entry * @return This zip entry * * @throws NullPointerException if the {@code time} is null * * @see #getLastAccessTime() * @since 1.8 */ public ZipEntry setLastAccessTime(FileTime time) { this.atime = Objects.requireNonNull(time, "lastAccessTime"); return this; } /** * Returns the last access time of the entry. * * <p> The last access time is from the extended timestamp fields * of entry's {@code optional extra data} when read from a ZIP file * or ZIP file formatted stream. * * @return The last access time of the entry, null if not specified * @see #setLastAccessTime(FileTime) * @since 1.8 */ public FileTime getLastAccessTime() { return atime; } /** * Sets the creation time of the entry. * * <p> If set, the creation time will be stored into the extended * timestamp fields of entry's {@code optional extra data}, when * output to a ZIP file or ZIP file formatted stream. * * @param time * The creation time of the entry * @return This zip entry * * @throws NullPointerException if the {@code time} is null * * @see #getCreationTime() * @since 1.8 */ public ZipEntry setCreationTime(FileTime time) { this.ctime = Objects.requireNonNull(time, "creationTime"); return this; } /** * Returns the creation time of the entry. * * <p> The creation time is from the extended timestamp fields of * entry's {@code optional extra data} when read from a ZIP file * or ZIP file formatted stream. * * @return the creation time of the entry, null if not specified * @see #setCreationTime(FileTime) * @since 1.8 */ public FileTime getCreationTime() { return ctime; } /** * Sets the uncompressed size of the entry data. * * @param size the uncompressed size in bytes * * @throws IllegalArgumentException if the specified size is less * than 0, is greater than 0xFFFFFFFF when * <a href="package-summary.html#zip64">ZIP64 format</a> is not supported, * or is less than 0 when ZIP64 is supported * @see #getSize() */ public void setSize(long size) { if (size < 0) { throw new IllegalArgumentException("invalid entry size"); } this.size = size; } /** * Returns the uncompressed size of the entry data. * * @return the uncompressed size of the entry data, or -1 if not known * @see #setSize(long) */ public long getSize() { return size; } /** * Returns the size of the compressed entry data. * * <p> In the case of a stored entry, the compressed size will be the same * as the uncompressed size of the entry. * * @return the size of the compressed entry data, or -1 if not known * @see #setCompressedSize(long) */ public long getCompressedSize() { return csize; } /** * Sets the size of the compressed entry data. * * @param csize the compressed size to set * * @see #getCompressedSize() */ public void setCompressedSize(long csize) { this.csize = csize; } /** * Sets the CRC-32 checksum of the uncompressed entry data. * * @param crc the CRC-32 value * * @throws IllegalArgumentException if the specified CRC-32 value is * less than 0 or greater than 0xFFFFFFFF * @see #getCrc() */ public void setCrc(long crc) { if (crc < 0 || crc > 0xFFFFFFFFL) { throw new IllegalArgumentException("invalid entry crc-32"); } this.crc = crc; } /** * Returns the CRC-32 checksum of the uncompressed entry data. * * @return the CRC-32 checksum of the uncompressed entry data, or -1 if * not known * * @see #setCrc(long) */ public long getCrc() { return crc; } /** * Sets the compression method for the entry. * * @param method the compression method, either STORED or DEFLATED * * @throws IllegalArgumentException if the specified compression * method is invalid * @see #getMethod() */ public void setMethod(int method) { if (method != STORED && method != DEFLATED) { throw new IllegalArgumentException("invalid compression method"); } this.method = method; } /** * Returns the compression method of the entry. * * @return the compression method of the entry, or -1 if not specified * @see #setMethod(int) */ public int getMethod() { return method; } /** * Sets the optional extra field data for the entry. * * <p> Invoking this method may change this entry's last modification * time, last access time and creation time, if the {@code extra} field * data includes the extensible timestamp fields, such as {@code NTFS tag * 0x0001} or {@code Info-ZIP Extended Timestamp}, as specified in * <a href="http://www.info-zip.org/doc/appnote-19970311-iz.zip">Info-ZIP * Application Note 970311</a>. * * @param extra * The extra field data bytes * * @throws IllegalArgumentException if the length of the specified * extra field data is greater than 0xFFFF bytes * * @see #getExtra() */ public void setExtra(byte[] extra) { setExtra0(extra, false); } /** * Sets the optional extra field data for the entry. * * @param extra * the extra field data bytes * @param doZIP64 * if true, set size and csize from ZIP64 fields if present */ void setExtra0(byte[] extra, boolean doZIP64) { if (extra != null) { if (extra.length > 0xFFFF) { throw new IllegalArgumentException("invalid extra field length"); } // extra fields are in "HeaderID(2)DataSize(2)Data... format int off = 0; int len = extra.length; while (off + 4 < len) { int tag = get16(extra, off); int sz = get16(extra, off + 2); off += 4; if (off + sz > len) // invalid data break; switch (tag) { case EXTID_ZIP64: if (doZIP64) { // LOC extra zip64 entry MUST include BOTH original // and compressed file size fields. // If invalid zip64 extra fields, simply skip. Even // it's rare, it's possible the entry size happens to // be the magic value and it "accidently" has some // bytes in extra match the id. if (sz >= 16) { size = get64(extra, off); csize = get64(extra, off + 8); } } break; case EXTID_NTFS: if (sz < 32) // reserved 4 bytes + tag 2 bytes + size 2 bytes break; // m[a|c]time 24 bytes int pos = off + 4; // reserved 4 bytes if (get16(extra, pos) != 0x0001 || get16(extra, pos + 2) != 24) break; long wtime = get64(extra, pos + 4); if (wtime != WINDOWS_TIME_NOT_AVAILABLE) { mtime = winTimeToFileTime(wtime); } wtime = get64(extra, pos + 12); if (wtime != WINDOWS_TIME_NOT_AVAILABLE) { atime = winTimeToFileTime(wtime); } wtime = get64(extra, pos + 20); if (wtime != WINDOWS_TIME_NOT_AVAILABLE) { ctime = winTimeToFileTime(wtime); } break; case EXTID_EXTT: int flag = Byte.toUnsignedInt(extra[off]); int sz0 = 1; // The CEN-header extra field contains the modification // time only, or no timestamp at all. 'sz' is used to // flag its presence or absence. But if mtime is present // in LOC it must be present in CEN as well. if ((flag & 0x1) != 0 && (sz0 + 4) <= sz) { mtime = unixTimeToFileTime(get32S(extra, off + sz0)); sz0 += 4; } if ((flag & 0x2) != 0 && (sz0 + 4) <= sz) { atime = unixTimeToFileTime(get32S(extra, off + sz0)); sz0 += 4; } if ((flag & 0x4) != 0 && (sz0 + 4) <= sz) { ctime = unixTimeToFileTime(get32S(extra, off + sz0)); sz0 += 4; } break; default: } off += sz; } } this.extra = extra; } /** * Returns the extra field data for the entry. * * @return the extra field data for the entry, or null if none * * @see #setExtra(byte[]) */ public byte[] getExtra() { return extra; } /** * Sets the optional comment string for the entry. * * <p>ZIP entry comments have maximum length of 0xffff. If the length of the * specified comment string is greater than 0xFFFF bytes after encoding, only * the first 0xFFFF bytes are output to the ZIP file entry. * * @param comment the comment string * * @see #getComment() */ public void setComment(String comment) { this.comment = comment; } /** * Returns the comment string for the entry. * * @return the comment string for the entry, or null if none * * @see #setComment(String) */ public String getComment() { return comment; } /** * Returns true if this is a directory entry. A directory entry is * defined to be one whose name ends with a '/'. * @return true if this is a directory entry */ public boolean isDirectory() { return name.endsWith("/"); } /** * Returns a string representation of the ZIP entry. */ public String toString() { return getName(); } /** * Returns the hash code value for this entry. */ public int hashCode() { return name.hashCode(); } /** * Returns a copy of this entry. */ public Object clone() { try { ZipEntry e = (ZipEntry) super.clone(); e.extra = (extra == null) ? null : extra.clone(); return e; } catch (CloneNotSupportedException e) { // This should never happen, since we are Cloneable throw new InternalError(e); } } }