src/main/java/org/apache/commons/compress/utils/TimeUtils.java

/*
 * 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
 *
 *   https://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 org.apache.commons.compress.utils;

import java.nio.file.attribute.FileTime;
import java.time.Instant;
import java.util.Date;
import java.util.concurrent.TimeUnit;

import org.apache.commons.io.file.attribute.FileTimes;

/**
 * Utility class for handling time-related types and conversions.
 * <p>
 * Understanding Unix vs NTFS timestamps:
 * </p>
 * <ul>
 * <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
 * Universal Time (UTC)</li>
 * <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
 * number of 100-nanosecond intervals that have elapsed since 12:00 A.M. January 1, 1601 Coordinated Universal Time (UTC).</li>
 * </ul>
 *
 * @since 1.23
 * @see FileTimes
 * @deprecated Use {@link FileTimes}.
 */
@Deprecated
public final class TimeUtils {

    /** The amount of 100-nanosecond intervals in one millisecond. */
    static final long HUNDRED_NANOS_PER_MILLISECOND = TimeUnit.MILLISECONDS.toNanos(1) / 100;

    /**
     * <a href="https://msdn.microsoft.com/en-us/library/windows/desktop/ms724290%28v=vs.85%29.aspx">Windows File Times</a>
     * <p>
     * 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
     * Universal Time (UTC). This is the offset of Windows time 0 to Unix epoch in 100-nanosecond intervals.
     * </p>
     */
    static final long WINDOWS_EPOCH_OFFSET = -116444736000000000L;

    /**
     * Tests whether a FileTime can be safely represented in the standard Unix time.
     *
     * @param time the FileTime to evaluate, can be null.
     * @return true if the time exceeds the minimum or maximum Unix time, false otherwise.
     * @deprecated use {@link FileTimes#isUnixTime(FileTime)}
     */
    @Deprecated
    public static boolean isUnixTime(final FileTime time) {
        return FileTimes.isUnixTime(time);
    }

    /**
     * Tests whether a given number of seconds (since Epoch) can be safely represented in the standard Unix time.
     *
     * @param seconds the number of seconds (since Epoch) to evaluate.
     * @return true if the time can be represented in the standard Unix time, false otherwise.
     * @deprecated Use {@link FileTimes#isUnixTime(long)}
     */
    @Deprecated
    public static boolean isUnixTime(final long seconds) {
        return FileTimes.isUnixTime(seconds);
    }

    /**
     * Converts NTFS time (100 nanosecond units since 1 January 1601) to Java time.
     *
     * @param ntfsTime the NTFS time in 100 nanosecond units.
     * @return the Date.
     * @deprecated Use {@link FileTimes#ntfsTimeToDate(long)}.
     */
    @Deprecated
    public static Date ntfsTimeToDate(final long ntfsTime) {
        return FileTimes.ntfsTimeToDate(ntfsTime);
    }

    /**
     * Converts NTFS time (100-nanosecond units since 1 January 1601) to a FileTime.
     *
     * @param ntfsTime the NTFS time in 100-nanosecond units.
     * @return the FileTime.
     * @see FileTimes#toNtfsTime(FileTime)
     * @deprecated Use {@link FileTimes#ntfsTimeToFileTime(long)}.
     */
    @Deprecated
    public static FileTime ntfsTimeToFileTime(final long ntfsTime) {
        return FileTimes.ntfsTimeToFileTime(ntfsTime);
    }

    /**
     * Converts {@link FileTime} to a {@link Date}. If the provided FileTime is {@code null}, the returned Date is also {@code null}.
     *
     * @param fileTime the file time to be converted.
     * @return a {@link Date} which corresponds to the supplied time, or {@code null} if the time is {@code null}.
     * @see FileTimes#toFileTime(Date)
     * @deprecated Use {@link FileTimes#toDate(FileTime)}.
     */
    @Deprecated
    public static Date toDate(final FileTime fileTime) {
        return FileTimes.toDate(fileTime);
    }

    /**
     * Converts {@link Date} to a {@link FileTime}. If the provided Date is {@code null}, the returned FileTime is also {@code null}.
     *
     * @param date the date to be converted.
     * @return a {@link FileTime} which corresponds to the supplied date, or {@code null} if the date is {@code null}.
     * @see FileTimes#toDate(FileTime)
     * @deprecated Use {@link FileTimes#toFileTime(Date)}.
     */
    @Deprecated
    public static FileTime toFileTime(final Date date) {
        return FileTimes.toFileTime(date);
    }

    /**
     * Converts a {@link Date} to NTFS time.
     *
     * @param date the Date.
     * @return the NTFS time.
     * @deprecated Use {@link FileTimes#toNtfsTime(Date)}.
     */
    @Deprecated
    public static long toNtfsTime(final Date date) {
        return FileTimes.toNtfsTime(date);
    }

    /**
     * Converts a {@link FileTime} to NTFS time (100-nanosecond units since 1 January 1601).
     *
     * @param fileTime the FileTime.
     * @return the NTFS time in 100-nanosecond units.
     * @see FileTimes#ntfsTimeToFileTime(long)
     * @deprecated Use {@link FileTimes#toNtfsTime(FileTime)}.
     */
    @Deprecated
    public static long toNtfsTime(final FileTime fileTime) {
        return FileTimes.toNtfsTime(fileTime);
    }

    /**
     * Converts Java time (milliseconds since Epoch) to NTFS time.
     *
     * @param javaTime the Java time.
     * @return the NTFS time.
     * @deprecated Use {@link FileTimes#toNtfsTime(long)}
     */
    @Deprecated
    public static long toNtfsTime(final long javaTime) {
        return FileTimes.toNtfsTime(javaTime);
    }

    /**
     * Converts a {@link FileTime} to standard Unix time in seconds.
     * <p>
     * The returned seconds value may lie out of bounds of Unix time. Check with {@link FileTimes#isUnixTime(long)}.
     * </p>
     *
     * @param fileTime the original FileTime.
     * @return the Unix timestamp or 0 if the input is null.
     * @see FileTimes#isUnixTime(long)
     * @deprecated Use {@link FileTimes#toUnixTime(FileTime)}.
     */
    @Deprecated
    public static long toUnixTime(final FileTime fileTime) {
        return FileTimes.toUnixTime(fileTime);
    }

    /**
     * Truncates a FileTime to 100-nanosecond precision.
     *
     * @param fileTime the FileTime to be truncated.
     * @return the truncated FileTime.
     * @deprecated No replacement, only used in tests.
     */
    @Deprecated
    public static FileTime truncateToHundredNanos(final FileTime fileTime) {
        final Instant instant = fileTime.toInstant();
        return FileTime.from(Instant.ofEpochSecond(instant.getEpochSecond(), instant.getNano() / 100 * 100));
    }

    /**
     * Converts standard Unix time (in seconds, UTC/GMT) to {@link FileTime}.
     *
     * @param time Unix timestamp (in seconds, UTC/GMT).
     * @return the corresponding FileTime.
     * @deprecated Use {@link FileTimes#fromUnixTime(long)}
     */
    @Deprecated
    public static FileTime unixTimeToFileTime(final long time) {
        return FileTimes.fromUnixTime(time);
    }

    /** Private constructor to prevent instantiation of this utility class. */
    private TimeUtils() {
    }
}