    001/*
    002 *  Licensed to the Apache Software Foundation (ASF) under one or more
    003 *  contributor license agreements.  See the NOTICE file distributed with
    004 *  this work for additional information regarding copyright ownership.
    005 *  The ASF licenses this file to You under the Apache License, Version 2.0
    006 *  (the "License"); you may not use this file except in compliance with
    007 *  the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 *  Unless required by applicable law or agreed to in writing, software
    012 *  distributed under the License is distributed on an "AS IS" BASIS,
    013 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 *  See the License for the specific language governing permissions and
    015 *  limitations under the License.
    016 */
    017package org.apache.commons.compress.utils;
    018
    019import java.nio.file.attribute.FileTime;
    020import java.time.Instant;
    021import java.util.Date;
    022import java.util.concurrent.TimeUnit;
    023
    024import org.apache.commons.io.file.attribute.FileTimes;
    025
    026/**
    027 * Utility class for handling time-related types and conversions.
    028 * <p>
    029 * Understanding UNIX vs NTFS timestamps:
    030 * </p>
    031 * <ul>
    032 * <li>A <a href="https://en.wikipedia.org/wiki/Unix_time">UNIX timestamp</a> is a primitive long starting at the UNIX Epoch on January 1st, 1970 at Coordinated
    033 * Universal Time (UTC)</li>
    034 * <li>An <a href="https://learn.microsoft.com/en-us/windows/win32/sysinfo/file-times">NTFS timestamp</a> is a file time is a 64-bit value that represents the
    035 * number of 100-nanosecond intervals that have elapsed since 12:00 A.M. January 1, 1601 Coordinated Universal Time (UTC).</li>
    036 * </ul>
    037 *
    038 * @since 1.23
    039 */
    040public final class TimeUtils {
    041
    042    /** The amount of 100-nanosecond intervals in one millisecond. */
    043    static final long HUNDRED_NANOS_PER_MILLISECOND = TimeUnit.MILLISECONDS.toNanos(1) / 100;
    044
    045    /**
    046     * <a href="https://msdn.microsoft.com/en-us/library/windows/desktop/ms724290%28v=vs.85%29.aspx">Windows File Times</a>
    047     * <p>
    048     * A file time is a 64-bit value that represents the number of 100-nanosecond intervals that have elapsed since 12:00 A.M. January 1, 1601 Coordinated
    049     * Universal Time (UTC). This is the offset of Windows time 0 to UNIX epoch in 100-nanosecond intervals.
    050     * </p>
    051     */
    052    static final long WINDOWS_EPOCH_OFFSET = -116444736000000000L;
    053
    054    /**
    055     * Tests whether a FileTime can be safely represented in the standard UNIX time.
    056     *
    057     * <p>
    058     * TODO ? If the FileTime is null, this method always returns true.
    059     * </p>
    060     *
    061     * @param time the FileTime to evaluate, can be null.
    062     * @return true if the time exceeds the minimum or maximum UNIX time, false otherwise.
    063     */
    064    public static boolean isUnixTime(final FileTime time) {
    065        // TODO Apache Commons IO 2.16.0
    066        return isUnixTime(toUnixTime(time));
    067    }
    068
    069    /**
    070     * Tests whether a given number of seconds (since Epoch) can be safely represented in the standard UNIX time.
    071     *
    072     * @param seconds the number of seconds (since Epoch) to evaluate.
    073     * @return true if the time can be represented in the standard UNIX time, false otherwise.
    074     */
    075    public static boolean isUnixTime(final long seconds) {
    076        // TODO Apache Commons IO 2.16.0
    077        return Integer.MIN_VALUE <= seconds && seconds <= Integer.MAX_VALUE;
    078    }
    079
    080    /**
    081     * Converts NTFS time (100 nanosecond units since 1 January 1601) to Java time.
    082     *
    083     * @param ntfsTime the NTFS time in 100 nanosecond units.
    084     * @return the Date.
    085     * @deprecated Use {@link FileTimes#ntfsTimeToDate(long)}.
    086     */
    087    @Deprecated
    088    public static Date ntfsTimeToDate(final long ntfsTime) {
    089        return FileTimes.ntfsTimeToDate(ntfsTime);
    090    }
    091
    092    /**
    093     * Converts NTFS time (100-nanosecond units since 1 January 1601) to a FileTime.
    094     *
    095     * @param ntfsTime the NTFS time in 100-nanosecond units.
    096     * @return the FileTime.
    097     * @see FileTimes#toNtfsTime(FileTime)
    098     * @deprecated Use {@link FileTimes#ntfsTimeToFileTime(long)}.
    099     */
    100    @Deprecated
    101    public static FileTime ntfsTimeToFileTime(final long ntfsTime) {
    102        return FileTimes.ntfsTimeToFileTime(ntfsTime);
    103    }
    104
    105    /**
    106     * Converts {@link FileTime} to a {@link Date}. If the provided FileTime is {@code null}, the returned Date is also {@code null}.
    107     *
    108     * @param fileTime the file time to be converted.
    109     * @return a {@link Date} which corresponds to the supplied time, or {@code null} if the time is {@code null}.
    110     * @see FileTimes#toFileTime(Date)
    111     * @deprecated Use {@link FileTimes#toDate(FileTime)}.
    112     */
    113    @Deprecated
    114    public static Date toDate(final FileTime fileTime) {
    115        return FileTimes.toDate(fileTime);
    116    }
    117
    118    /**
    119     * Converts {@link Date} to a {@link FileTime}. If the provided Date is {@code null}, the returned FileTime is also {@code null}.
    120     *
    121     * @param date the date to be converted.
    122     * @return a {@link FileTime} which corresponds to the supplied date, or {@code null} if the date is {@code null}.
    123     * @see FileTimes#toDate(FileTime)
    124     * @deprecated Use {@link FileTimes#toFileTime(Date)}.
    125     */
    126    @Deprecated
    127    public static FileTime toFileTime(final Date date) {
    128        return FileTimes.toFileTime(date);
    129    }
    130
    131    /**
    132     * Converts a {@link Date} to NTFS time.
    133     *
    134     * @param date the Date.
    135     * @return the NTFS time.
    136     * @deprecated Use {@link FileTimes#toNtfsTime(Date)}.
    137     */
    138    @Deprecated
    139    public static long toNtfsTime(final Date date) {
    140        return FileTimes.toNtfsTime(date);
    141    }
    142
    143    /**
    144     * Converts a {@link FileTime} to NTFS time (100-nanosecond units since 1 January 1601).
    145     *
    146     * @param fileTime the FileTime.
    147     * @return the NTFS time in 100-nanosecond units.
    148     * @see FileTimes#ntfsTimeToFileTime(long)
    149     * @deprecated Use {@link FileTimes#toNtfsTime(FileTime)}.
    150     */
    151    @Deprecated
    152    public static long toNtfsTime(final FileTime fileTime) {
    153        return FileTimes.toNtfsTime(fileTime);
    154    }
    155
    156    /**
    157     * Converts Java time (milliseconds since Epoch) to NTFS time.
    158     *
    159     * @param javaTime the Java time.
    160     * @return the NTFS time.
    161     */
    162    public static long toNtfsTime(final long javaTime) {
    163        // TODO Apache Commons IO 2.16.0
    164        final long javaHundredNanos = javaTime * HUNDRED_NANOS_PER_MILLISECOND;
    165        return Math.subtractExact(javaHundredNanos, WINDOWS_EPOCH_OFFSET);
    166    }
    167
    168    /**
    169     * Converts {@link FileTime} to standard UNIX time.
    170     *
    171     * @param fileTime the original FileTime.
    172     * @return the UNIX timestamp.
    173     */
    174    public static long toUnixTime(final FileTime fileTime) {
    175        // TODO Apache Commons IO 2.16.0
    176        return fileTime != null ? fileTime.to(TimeUnit.SECONDS) : 0;
    177    }
    178
    179    /**
    180     * Truncates a FileTime to 100-nanosecond precision.
    181     *
    182     * @param fileTime the FileTime to be truncated.
    183     * @return the truncated FileTime.
    184     */
    185    public static FileTime truncateToHundredNanos(final FileTime fileTime) {
    186        final Instant instant = fileTime.toInstant();
    187        return FileTime.from(Instant.ofEpochSecond(instant.getEpochSecond(), instant.getNano() / 100 * 100));
    188    }
    189
    190    /**
    191     * Converts standard UNIX time (in seconds, UTC/GMT) to {@link FileTime}.
    192     *
    193     * @param time UNIX timestamp (in seconds, UTC/GMT).
    194     * @return the corresponding FileTime.
    195     */
    196    public static FileTime unixTimeToFileTime(final long time) {
    197        // TODO Apache Commons IO 2.16.0 FileTimes.fromUnixTime(long)
    198        return FileTime.from(time, TimeUnit.SECONDS);
    199    }
    200
    201    /** Private constructor to prevent instantiation of this utility class. */
    202    private TimeUtils() {
    203    }
    204}