src/main/java/org/apache/commons/compress/archivers/zip/X5455_ExtendedTimestamp.java - platform/external/apache-commons-compress - Git at Google

 /*
  * 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 org.apache.commons.compress.archivers.zip;

 import java.io.Serializable;
 import java.util.Date;
 import java.util.zip.ZipException;

 /**
  * <p>An extra field that stores additional file and directory timestamp data
  * for zip entries.   Each zip entry can include up to three timestamps
  * (modify, access, create*).  The timestamps are stored as 32 bit signed
  * integers representing seconds since UNIX epoch (Jan 1st, 1970, UTC).
  * This field improves on zip's default timestamp granularity, since it
  * allows one to store additional timestamps, and, in addition, the timestamps
  * are stored using per-second granularity (zip's default behaviour can only store
  * timestamps to the nearest <em>even</em> second).
  * </p><p>
  * Unfortunately, 32 (signed) bits can only store dates up to the year 2037,
  * and so this extra field will eventually be obsolete.  Enjoy it while it lasts!
  * </p>
  * <ul>
  * <li><b>modifyTime:</b>
  * most recent time of file/directory modification
  * (or file/dir creation if the entry has not been
  * modified since it was created).
  * </li>
  * <li><b>accessTime:</b>
  * most recent time file/directory was opened
  * (e.g., read from disk).  Many people disable
  * their operating systems from updating this value
  * using the NOATIME mount option to optimize disk behaviour,
  * and thus it's not always reliable.  In those cases
  * it's always equal to modifyTime.
  * </li>
  * <li><b>*createTime:</b>
  * modern linux file systems (e.g., ext2 and newer)
  * do not appear to store a value like this, and so
  * it's usually omitted altogether in the zip extra
  * field.  Perhaps other unix systems track this.
  * </li></ul>
  * <p>
  * We're using the field definition given in Info-Zip's source archive:
  * zip-3.0.tar.gz/proginfo/extrafld.txt
  * </p>
  * <pre>
  * Value         Size        Description
  * -----         ----        -----------
  * 0x5455        Short       tag for this extra block type ("UT")
  * TSize         Short       total data size for this block
  * Flags         Byte        info bits
  * (ModTime)     Long        time of last modification (UTC/GMT)
  * (AcTime)      Long        time of last access (UTC/GMT)
  * (CrTime)      Long        time of original creation (UTC/GMT)
  *
  * Central-header version:
  *
  * Value         Size        Description
  * -----         ----        -----------
  * 0x5455        Short       tag for this extra block type ("UT")
  * TSize         Short       total data size for this block
  * Flags         Byte        info bits (refers to local header!)
  * (ModTime)     Long        time of last modification (UTC/GMT)
  * </pre>
  * @since 1.5
  */
 public class X5455_ExtendedTimestamp implements ZipExtraField, Cloneable, Serializable {
     private static final ZipShort HEADER_ID = new ZipShort(0x5455);
     private static final long serialVersionUID = 1L;

     /**
      * The bit set inside the flags by when the last modification time
      * is present in this extra field.
      */
     public static final byte MODIFY_TIME_BIT = 1;
     /**
      * The bit set inside the flags by when the lasr access time is
      * present in this extra field.
      */
     public static final byte ACCESS_TIME_BIT = 2;
     /**
      * The bit set inside the flags by when the original creation time
      * is present in this extra field.
      */
     public static final byte CREATE_TIME_BIT = 4;

     // The 3 boolean fields (below) come from this flags byte.  The remaining 5 bits
     // are ignored according to the current version of the spec (December 2012).
     private byte flags;

     // Note: even if bit1 and bit2 are set, the Central data will still not contain
     // access/create fields:  only local data ever holds those!  This causes
     // some of our implementation to look a little odd, with seemingly spurious
     // != null and length checks.
     private boolean bit0_modifyTimePresent;
     private boolean bit1_accessTimePresent;
     private boolean bit2_createTimePresent;

     private ZipLong modifyTime;
     private ZipLong accessTime;
     private ZipLong createTime;

     /**
      * Constructor for X5455_ExtendedTimestamp.
      */
     public X5455_ExtendedTimestamp() {}

     /**
      * The Header-ID.
      *
      * @return the value for the header id for this extrafield
      */
     @Override
     public ZipShort getHeaderId() {
         return HEADER_ID;
     }

     /**
      * Length of the extra field in the local file data - without
      * Header-ID or length specifier.
      *
      * @return a <code>ZipShort</code> for the length of the data of this extra field
      */
     @Override
     public ZipShort getLocalFileDataLength() {
         return new ZipShort(1 +
                 (bit0_modifyTimePresent ? 4 : 0) +
                 (bit1_accessTimePresent && accessTime != null ? 4 : 0) +
                 (bit2_createTimePresent && createTime != null ? 4 : 0)
         );
     }

     /**
      * Length of the extra field in the local file data - without
      * Header-ID or length specifier.
      *
      * <p>For X5455 the central length is often smaller than the
      * local length, because central cannot contain access or create
      * timestamps.</p>
      *
      * @return a <code>ZipShort</code> for the length of the data of this extra field
      */
     @Override
     public ZipShort getCentralDirectoryLength() {
         return new ZipShort(1 +
                 (bit0_modifyTimePresent ? 4 : 0)
         );
     }

     /**
      * The actual data to put into local file data - without Header-ID
      * or length specifier.
      *
      * @return get the data
      */
     @Override
     public byte[] getLocalFileDataData() {
         final byte[] data = new byte[getLocalFileDataLength().getValue()];
         int pos = 0;
         data[pos++] = 0;
         if (bit0_modifyTimePresent) {
             data[0] |= MODIFY_TIME_BIT;
             System.arraycopy(modifyTime.getBytes(), 0, data, pos, 4);
             pos += 4;
         }
         if (bit1_accessTimePresent && accessTime != null) {
             data[0] |= ACCESS_TIME_BIT;
             System.arraycopy(accessTime.getBytes(), 0, data, pos, 4);
             pos += 4;
         }
         if (bit2_createTimePresent && createTime != null) {
             data[0] |= CREATE_TIME_BIT;
             System.arraycopy(createTime.getBytes(), 0, data, pos, 4);
             pos += 4; // NOSONAR - assignment as documentation
         }
         return data;
     }

     /**
      * The actual data to put into central directory data - without Header-ID
      * or length specifier.
      *
      * @return the central directory data
      */
     @Override
     public byte[] getCentralDirectoryData() {
         final byte[] centralData = new byte[getCentralDirectoryLength().getValue()];
         final byte[] localData = getLocalFileDataData();

         // Truncate out create & access time (last 8 bytes) from
         // the copy of the local data we obtained:
         System.arraycopy(localData, 0, centralData, 0, centralData.length);
         return centralData;
     }

     /**
      * Populate data from this array as if it was in local file data.
      *
      * @param data   an array of bytes
      * @param offset the start offset
      * @param length the number of bytes in the array from offset
      * @throws java.util.zip.ZipException on error
      */
     @Override
     public void parseFromLocalFileData(
             final byte[] data, int offset, final int length
     ) throws ZipException {
         reset();
         final int len = offset + length;
         setFlags(data[offset++]);
         if (bit0_modifyTimePresent) {
             modifyTime = new ZipLong(data, offset);
             offset += 4;
         }

         // Notice the extra length check in case we are parsing the shorter
         // central data field (for both access and create timestamps).
         if (bit1_accessTimePresent && offset + 4 <= len) {
             accessTime = new ZipLong(data, offset);
             offset += 4;
         }
         if (bit2_createTimePresent && offset + 4 <= len) {
             createTime = new ZipLong(data, offset);
             offset += 4; // NOSONAR - assignment as documentation
         }
     }

     /**
      * Doesn't do anything special since this class always uses the
      * same parsing logic for both central directory and local file data.
      */
     @Override
     public void parseFromCentralDirectoryData(
             final byte[] buffer, final int offset, final int length
     ) throws ZipException {
         reset();
         parseFromLocalFileData(buffer, offset, length);
     }

     /**
      * Reset state back to newly constructed state.  Helps us make sure
      * parse() calls always generate clean results.
      */
     private void reset() {
         setFlags((byte) 0);
         this.modifyTime = null;
         this.accessTime = null;
         this.createTime = null;
     }

     /**
      * Sets flags byte.  The flags byte tells us which of the
      * three datestamp fields are present in the data:
      * <pre>
      * bit0 - modify time
      * bit1 - access time
      * bit2 - create time
      * </pre>
      * Only first 3 bits of flags are used according to the
      * latest version of the spec (December 2012).
      *
      * @param flags flags byte indicating which of the
      *              three datestamp fields are present.
      */
     public void setFlags(final byte flags) {
         this.flags = flags;
         this.bit0_modifyTimePresent = (flags & MODIFY_TIME_BIT) == MODIFY_TIME_BIT;
         this.bit1_accessTimePresent = (flags & ACCESS_TIME_BIT) == ACCESS_TIME_BIT;
         this.bit2_createTimePresent = (flags & CREATE_TIME_BIT) == CREATE_TIME_BIT;
     }

     /**
      * Gets flags byte.  The flags byte tells us which of the
      * three datestamp fields are present in the data:
      * <pre>
      * bit0 - modify time
      * bit1 - access time
      * bit2 - create time
      * </pre>
      * Only first 3 bits of flags are used according to the
      * latest version of the spec (December 2012).
      *
      * @return flags byte indicating which of the
      *         three datestamp fields are present.
      */
     public byte getFlags() { return flags; }

     /**
      * Returns whether bit0 of the flags byte is set or not,
      * which should correspond to the presence or absence of
      * a modify timestamp in this particular zip entry.
      *
      * @return true if bit0 of the flags byte is set.
      */
     public boolean isBit0_modifyTimePresent() { return bit0_modifyTimePresent; }

     /**
      * Returns whether bit1 of the flags byte is set or not,
      * which should correspond to the presence or absence of
      * a "last access" timestamp in this particular zip entry.
      *
      * @return true if bit1 of the flags byte is set.
      */
     public boolean isBit1_accessTimePresent() { return bit1_accessTimePresent; }

     /**
      * Returns whether bit2 of the flags byte is set or not,
      * which should correspond to the presence or absence of
      * a create timestamp in this particular zip entry.
      *
      * @return true if bit2 of the flags byte is set.
      */
     public boolean isBit2_createTimePresent() { return bit2_createTimePresent; }

     /**
      * Returns the modify time (seconds since epoch) of this zip entry
      * as a ZipLong object, or null if no such timestamp exists in the
      * zip entry.
      *
      * @return modify time (seconds since epoch) or null.
      */
     public ZipLong getModifyTime() { return modifyTime; }

     /**
      * Returns the access time (seconds since epoch) of this zip entry
      * as a ZipLong object, or null if no such timestamp exists in the
      * zip entry.
      *
      * @return access time (seconds since epoch) or null.
      */
     public ZipLong getAccessTime() { return accessTime; }

     /**
      * <p>
      * Returns the create time (seconds since epoch) of this zip entry
      * as a ZipLong object, or null if no such timestamp exists in the
      * zip entry.
      * </p><p>
      * Note: modern linux file systems (e.g., ext2)
      * do not appear to store a "create time" value, and so
      * it's usually omitted altogether in the zip extra
      * field.  Perhaps other unix systems track this.
      *
      * @return create time (seconds since epoch) or null.
      */
     public ZipLong getCreateTime() { return createTime; }

     /**
      * Returns the modify time as a java.util.Date
      * of this zip entry, or null if no such timestamp exists in the zip entry.
      * The milliseconds are always zeroed out, since the underlying data
      * offers only per-second precision.
      *
      * @return modify time as java.util.Date or null.
      */
     public Date getModifyJavaTime() {
         return zipLongToDate(modifyTime);
     }

     /**
      * Returns the access time as a java.util.Date
      * of this zip entry, or null if no such timestamp exists in the zip entry.
      * The milliseconds are always zeroed out, since the underlying data
      * offers only per-second precision.
      *
      * @return access time as java.util.Date or null.
      */
     public Date getAccessJavaTime() {
         return zipLongToDate(accessTime);
     }

     /**
      * <p>
      * Returns the create time as a a java.util.Date
      * of this zip entry, or null if no such timestamp exists in the zip entry.
      * The milliseconds are always zeroed out, since the underlying data
      * offers only per-second precision.
      * </p><p>
      * Note: modern linux file systems (e.g., ext2)
      * do not appear to store a "create time" value, and so
      * it's usually omitted altogether in the zip extra
      * field.  Perhaps other unix systems track this.
      *
      * @return create time as java.util.Date or null.
      */
     public Date getCreateJavaTime() {
         return zipLongToDate(createTime);
     }

     /**
      * <p>
      * Sets the modify time (seconds since epoch) of this zip entry
      * using a ZipLong object.
      * </p><p>
      * Note: the setters for flags and timestamps are decoupled.
      * Even if the timestamp is not-null, it will only be written
      * out if the corresponding bit in the flags is also set.
      * </p>
      *
      * @param l ZipLong of the modify time (seconds per epoch)
      */
     public void setModifyTime(final ZipLong l) {
         bit0_modifyTimePresent = l != null;
         flags = (byte) (l != null ? (flags | MODIFY_TIME_BIT)
                         : (flags & ~MODIFY_TIME_BIT));
         this.modifyTime = l;
     }

     /**
      * <p>
      * Sets the access time (seconds since epoch) of this zip entry
      * using a ZipLong object
      * </p><p>
      * Note: the setters for flags and timestamps are decoupled.
      * Even if the timestamp is not-null, it will only be written
      * out if the corresponding bit in the flags is also set.
      * </p>
      *
      * @param l ZipLong of the access time (seconds per epoch)
      */
     public void setAccessTime(final ZipLong l) {
         bit1_accessTimePresent = l != null;
         flags = (byte) (l != null ? (flags | ACCESS_TIME_BIT)
                         : (flags & ~ACCESS_TIME_BIT));
         this.accessTime = l;
     }

     /**
      * <p>
      * Sets the create time (seconds since epoch) of this zip entry
      * using a ZipLong object
      * </p><p>
      * Note: the setters for flags and timestamps are decoupled.
      * Even if the timestamp is not-null, it will only be written
      * out if the corresponding bit in the flags is also set.
      * </p>
      *
      * @param l ZipLong of the create time (seconds per epoch)
      */
     public void setCreateTime(final ZipLong l) {
         bit2_createTimePresent = l != null;
         flags = (byte) (l != null ? (flags | CREATE_TIME_BIT)
                         : (flags & ~CREATE_TIME_BIT));
         this.createTime = l;
     }

     /**
      * <p>
      * Sets the modify time as a java.util.Date
      * of this zip entry.  Supplied value is truncated to per-second
      * precision (milliseconds zeroed-out).
      * </p><p>
      * Note: the setters for flags and timestamps are decoupled.
      * Even if the timestamp is not-null, it will only be written
      * out if the corresponding bit in the flags is also set.
      * </p>
      *
      * @param d modify time as java.util.Date
      */
     public void setModifyJavaTime(final Date d) { setModifyTime(dateToZipLong(d)); }

     /**
      * <p>
      * Sets the access time as a java.util.Date
      * of this zip entry.  Supplied value is truncated to per-second
      * precision (milliseconds zeroed-out).
      * </p><p>
      * Note: the setters for flags and timestamps are decoupled.
      * Even if the timestamp is not-null, it will only be written
      * out if the corresponding bit in the flags is also set.
      * </p>
      *
      * @param d access time as java.util.Date
      */
     public void setAccessJavaTime(final Date d) { setAccessTime(dateToZipLong(d)); }

     /**
      * <p>
      * Sets the create time as a java.util.Date
      * of this zip entry.  Supplied value is truncated to per-second
      * precision (milliseconds zeroed-out).
      * </p><p>
      * Note: the setters for flags and timestamps are decoupled.
      * Even if the timestamp is not-null, it will only be written
      * out if the corresponding bit in the flags is also set.
      * </p>
      *
      * @param d create time as java.util.Date
      */
     public void setCreateJavaTime(final Date d) { setCreateTime(dateToZipLong(d)); }

     /**
      * Utility method converts java.util.Date (milliseconds since epoch)
      * into a ZipLong (seconds since epoch).
      * <p/>
      * Also makes sure the converted ZipLong is not too big to fit
      * in 32 unsigned bits.
      *
      * @param d java.util.Date to convert to ZipLong
      * @return ZipLong
      */
     private static ZipLong dateToZipLong(final Date d) {
         if (d == null) { return null; }

         return unixTimeToZipLong(d.getTime() / 1000);
     }

     /**
      * Returns a String representation of this class useful for
      * debugging purposes.
      *
      * @return A String representation of this class useful for
      *         debugging purposes.
      */
     @Override
     public String toString() {
         final StringBuilder buf = new StringBuilder();
         buf.append("0x5455 Zip Extra Field: Flags=");
         buf.append(Integer.toBinaryString(ZipUtil.unsignedIntToSignedByte(flags))).append(" ");
         if (bit0_modifyTimePresent && modifyTime != null) {
             final Date m = getModifyJavaTime();
             buf.append(" Modify:[").append(m).append("] ");
         }
         if (bit1_accessTimePresent && accessTime != null) {
             final Date a = getAccessJavaTime();
             buf.append(" Access:[").append(a).append("] ");
         }
         if (bit2_createTimePresent && createTime != null) {
             final Date c = getCreateJavaTime();
             buf.append(" Create:[").append(c).append("] ");
         }
         return buf.toString();
     }

     @Override
     public Object clone() throws CloneNotSupportedException {
         return super.clone();
     }

     @Override
     public boolean equals(final Object o) {
         if (o instanceof X5455_ExtendedTimestamp) {
             final X5455_ExtendedTimestamp xf = (X5455_ExtendedTimestamp) o;

             // The ZipLong==ZipLong clauses handle the cases where both are null.
             // and only last 3 bits of flags matter.
             return ((flags & 0x07) == (xf.flags & 0x07)) &&
                     (modifyTime == xf.modifyTime || (modifyTime != null && modifyTime.equals(xf.modifyTime))) &&
                     (accessTime == xf.accessTime || (accessTime != null && accessTime.equals(xf.accessTime))) &&
                     (createTime == xf.createTime || (createTime != null && createTime.equals(xf.createTime)));
         }
         return false;
     }

     @Override
     public int hashCode() {
         int hc = (-123 * (flags & 0x07)); // only last 3 bits of flags matter
         if (modifyTime != null) {
             hc ^= modifyTime.hashCode();
         }
         if (accessTime != null) {
             // Since accessTime is often same as modifyTime,
             // this prevents them from XOR negating each other.
             hc ^= Integer.rotateLeft(accessTime.hashCode(), 11);
         }
         if (createTime != null) {
             hc ^= Integer.rotateLeft(createTime.hashCode(), 22);
         }
         return hc;
     }

     private static Date zipLongToDate(ZipLong unixTime) {
         return unixTime != null ? new Date(unixTime.getIntValue() * 1000L) : null;
     }

     private static ZipLong unixTimeToZipLong(long l) {
         if (l < Integer.MIN_VALUE || l > Integer.MAX_VALUE) {
             throw new IllegalArgumentException("X5455 timestamps must fit in a signed 32 bit integer: " + l);
         }
         return new ZipLong(l);
     }

 }
	/*
	* 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 org.apache.commons.compress.archivers.zip;

	import java.io.Serializable;
	import java.util.Date;
	import java.util.zip.ZipException;

	/**
	* <p>An extra field that stores additional file and directory timestamp data
	* for zip entries. Each zip entry can include up to three timestamps
	* (modify, access, create*). The timestamps are stored as 32 bit signed
	* integers representing seconds since UNIX epoch (Jan 1st, 1970, UTC).
	* This field improves on zip's default timestamp granularity, since it
	* allows one to store additional timestamps, and, in addition, the timestamps
	* are stored using per-second granularity (zip's default behaviour can only store
	* timestamps to the nearest <em>even</em> second).
	* </p><p>
	* Unfortunately, 32 (signed) bits can only store dates up to the year 2037,
	* and so this extra field will eventually be obsolete. Enjoy it while it lasts!
	* </p>
	* <ul>
	* <li><b>modifyTime:</b>
	* most recent time of file/directory modification
	* (or file/dir creation if the entry has not been
	* modified since it was created).
	* </li>
	* <li><b>accessTime:</b>
	* most recent time file/directory was opened
	* (e.g., read from disk). Many people disable
	* their operating systems from updating this value
	* using the NOATIME mount option to optimize disk behaviour,
	* and thus it's not always reliable. In those cases
	* it's always equal to modifyTime.
	* </li>
	* <li><b>*createTime:</b>
	* modern linux file systems (e.g., ext2 and newer)
	* do not appear to store a value like this, and so
	* it's usually omitted altogether in the zip extra
	* field. Perhaps other unix systems track this.
	* </li></ul>
	* <p>
	* We're using the field definition given in Info-Zip's source archive:
	* zip-3.0.tar.gz/proginfo/extrafld.txt
	* </p>
	* <pre>
	* Value Size Description
	* ----- ---- -----------
	* 0x5455 Short tag for this extra block type ("UT")
	* TSize Short total data size for this block
	* Flags Byte info bits
	* (ModTime) Long time of last modification (UTC/GMT)
	* (AcTime) Long time of last access (UTC/GMT)
	* (CrTime) Long time of original creation (UTC/GMT)
	*
	* Central-header version:
	*
	* Value Size Description
	* ----- ---- -----------
	* 0x5455 Short tag for this extra block type ("UT")
	* TSize Short total data size for this block
	* Flags Byte info bits (refers to local header!)
	* (ModTime) Long time of last modification (UTC/GMT)
	* </pre>
	* @since 1.5
	*/
	public class X5455_ExtendedTimestamp implements ZipExtraField, Cloneable, Serializable {
	private static final ZipShort HEADER_ID = new ZipShort(0x5455);
	private static final long serialVersionUID = 1L;

	/**
	* The bit set inside the flags by when the last modification time
	* is present in this extra field.
	*/
	public static final byte MODIFY_TIME_BIT = 1;
	/**
	* The bit set inside the flags by when the lasr access time is
	* present in this extra field.
	*/
	public static final byte ACCESS_TIME_BIT = 2;
	/**
	* The bit set inside the flags by when the original creation time
	* is present in this extra field.
	*/
	public static final byte CREATE_TIME_BIT = 4;

	// The 3 boolean fields (below) come from this flags byte. The remaining 5 bits
	// are ignored according to the current version of the spec (December 2012).
	private byte flags;

	// Note: even if bit1 and bit2 are set, the Central data will still not contain
	// access/create fields: only local data ever holds those! This causes
	// some of our implementation to look a little odd, with seemingly spurious
	// != null and length checks.
	private boolean bit0_modifyTimePresent;
	private boolean bit1_accessTimePresent;
	private boolean bit2_createTimePresent;

	private ZipLong modifyTime;
	private ZipLong accessTime;
	private ZipLong createTime;

	/**
	* Constructor for X5455_ExtendedTimestamp.
	*/
	public X5455_ExtendedTimestamp() {}

	/**
	* The Header-ID.
	*
	* @return the value for the header id for this extrafield
	*/
	@Override
	public ZipShort getHeaderId() {
	return HEADER_ID;
	}

	/**
	* Length of the extra field in the local file data - without
	* Header-ID or length specifier.
	*
	* @return a <code>ZipShort</code> for the length of the data of this extra field
	*/
	@Override
	public ZipShort getLocalFileDataLength() {
	return new ZipShort(1 +
	(bit0_modifyTimePresent ? 4 : 0) +
	(bit1_accessTimePresent && accessTime != null ? 4 : 0) +
	(bit2_createTimePresent && createTime != null ? 4 : 0)
	);
	}

	/**
	* Length of the extra field in the local file data - without
	* Header-ID or length specifier.
	*
	* <p>For X5455 the central length is often smaller than the
	* local length, because central cannot contain access or create
	* timestamps.</p>
	*
	* @return a <code>ZipShort</code> for the length of the data of this extra field
	*/
	@Override
	public ZipShort getCentralDirectoryLength() {
	return new ZipShort(1 +
	(bit0_modifyTimePresent ? 4 : 0)
	);
	}

	/**
	* The actual data to put into local file data - without Header-ID
	* or length specifier.
	*
	* @return get the data
	*/
	@Override
	public byte[] getLocalFileDataData() {
	final byte[] data = new byte[getLocalFileDataLength().getValue()];
	int pos = 0;
	data[pos++] = 0;
	if (bit0_modifyTimePresent) {
	data[0] \|= MODIFY_TIME_BIT;
	System.arraycopy(modifyTime.getBytes(), 0, data, pos, 4);
	pos += 4;
	}
	if (bit1_accessTimePresent && accessTime != null) {
	data[0] \|= ACCESS_TIME_BIT;
	System.arraycopy(accessTime.getBytes(), 0, data, pos, 4);
	pos += 4;
	}
	if (bit2_createTimePresent && createTime != null) {
	data[0] \|= CREATE_TIME_BIT;
	System.arraycopy(createTime.getBytes(), 0, data, pos, 4);
	pos += 4; // NOSONAR - assignment as documentation
	}
	return data;
	}

	/**
	* The actual data to put into central directory data - without Header-ID
	* or length specifier.
	*
	* @return the central directory data
	*/
	@Override
	public byte[] getCentralDirectoryData() {
	final byte[] centralData = new byte[getCentralDirectoryLength().getValue()];
	final byte[] localData = getLocalFileDataData();

	// Truncate out create & access time (last 8 bytes) from
	// the copy of the local data we obtained:
	System.arraycopy(localData, 0, centralData, 0, centralData.length);
	return centralData;
	}

	/**
	* Populate data from this array as if it was in local file data.
	*
	* @param data an array of bytes
	* @param offset the start offset
	* @param length the number of bytes in the array from offset
	* @throws java.util.zip.ZipException on error
	*/
	@Override
	public void parseFromLocalFileData(
	final byte[] data, int offset, final int length
	) throws ZipException {
	reset();
	final int len = offset + length;
	setFlags(data[offset++]);
	if (bit0_modifyTimePresent) {
	modifyTime = new ZipLong(data, offset);
	offset += 4;
	}

	// Notice the extra length check in case we are parsing the shorter
	// central data field (for both access and create timestamps).
	if (bit1_accessTimePresent && offset + 4 <= len) {
	accessTime = new ZipLong(data, offset);
	offset += 4;
	}
	if (bit2_createTimePresent && offset + 4 <= len) {
	createTime = new ZipLong(data, offset);
	offset += 4; // NOSONAR - assignment as documentation
	}
	}

	/**
	* Doesn't do anything special since this class always uses the
	* same parsing logic for both central directory and local file data.
	*/
	@Override
	public void parseFromCentralDirectoryData(
	final byte[] buffer, final int offset, final int length
	) throws ZipException {
	reset();
	parseFromLocalFileData(buffer, offset, length);
	}

	/**
	* Reset state back to newly constructed state. Helps us make sure
	* parse() calls always generate clean results.
	*/
	private void reset() {
	setFlags((byte) 0);
	this.modifyTime = null;
	this.accessTime = null;
	this.createTime = null;
	}

	/**
	* Sets flags byte. The flags byte tells us which of the
	* three datestamp fields are present in the data:
	* <pre>
	* bit0 - modify time
	* bit1 - access time
	* bit2 - create time
	* </pre>
	* Only first 3 bits of flags are used according to the
	* latest version of the spec (December 2012).
	*
	* @param flags flags byte indicating which of the
	* three datestamp fields are present.
	*/
	public void setFlags(final byte flags) {
	this.flags = flags;
	this.bit0_modifyTimePresent = (flags & MODIFY_TIME_BIT) == MODIFY_TIME_BIT;
	this.bit1_accessTimePresent = (flags & ACCESS_TIME_BIT) == ACCESS_TIME_BIT;
	this.bit2_createTimePresent = (flags & CREATE_TIME_BIT) == CREATE_TIME_BIT;
	}

	/**
	* Gets flags byte. The flags byte tells us which of the
	* three datestamp fields are present in the data:
	* <pre>
	* bit0 - modify time
	* bit1 - access time
	* bit2 - create time
	* </pre>
	* Only first 3 bits of flags are used according to the
	* latest version of the spec (December 2012).
	*
	* @return flags byte indicating which of the
	* three datestamp fields are present.
	*/
	public byte getFlags() { return flags; }

	/**
	* Returns whether bit0 of the flags byte is set or not,
	* which should correspond to the presence or absence of
	* a modify timestamp in this particular zip entry.
	*
	* @return true if bit0 of the flags byte is set.
	*/
	public boolean isBit0_modifyTimePresent() { return bit0_modifyTimePresent; }

	/**
	* Returns whether bit1 of the flags byte is set or not,
	* which should correspond to the presence or absence of
	* a "last access" timestamp in this particular zip entry.
	*
	* @return true if bit1 of the flags byte is set.
	*/
	public boolean isBit1_accessTimePresent() { return bit1_accessTimePresent; }

	/**
	* Returns whether bit2 of the flags byte is set or not,
	* which should correspond to the presence or absence of
	* a create timestamp in this particular zip entry.
	*
	* @return true if bit2 of the flags byte is set.
	*/
	public boolean isBit2_createTimePresent() { return bit2_createTimePresent; }

	/**
	* Returns the modify time (seconds since epoch) of this zip entry
	* as a ZipLong object, or null if no such timestamp exists in the
	* zip entry.
	*
	* @return modify time (seconds since epoch) or null.
	*/
	public ZipLong getModifyTime() { return modifyTime; }

	/**
	* Returns the access time (seconds since epoch) of this zip entry
	* as a ZipLong object, or null if no such timestamp exists in the
	* zip entry.
	*
	* @return access time (seconds since epoch) or null.
	*/
	public ZipLong getAccessTime() { return accessTime; }

	/**
	* <p>
	* Returns the create time (seconds since epoch) of this zip entry
	* as a ZipLong object, or null if no such timestamp exists in the
	* zip entry.
	* </p><p>
	* Note: modern linux file systems (e.g., ext2)
	* do not appear to store a "create time" value, and so
	* it's usually omitted altogether in the zip extra
	* field. Perhaps other unix systems track this.
	*
	* @return create time (seconds since epoch) or null.
	*/
	public ZipLong getCreateTime() { return createTime; }

	/**
	* Returns the modify time as a java.util.Date
	* of this zip entry, or null if no such timestamp exists in the zip entry.
	* The milliseconds are always zeroed out, since the underlying data
	* offers only per-second precision.
	*
	* @return modify time as java.util.Date or null.
	*/
	public Date getModifyJavaTime() {
	return zipLongToDate(modifyTime);
	}

	/**
	* Returns the access time as a java.util.Date
	* of this zip entry, or null if no such timestamp exists in the zip entry.
	* The milliseconds are always zeroed out, since the underlying data
	* offers only per-second precision.
	*
	* @return access time as java.util.Date or null.
	*/
	public Date getAccessJavaTime() {
	return zipLongToDate(accessTime);
	}

	/**
	* <p>
	* Returns the create time as a a java.util.Date
	* of this zip entry, or null if no such timestamp exists in the zip entry.
	* The milliseconds are always zeroed out, since the underlying data
	* offers only per-second precision.
	* </p><p>
	* Note: modern linux file systems (e.g., ext2)
	* do not appear to store a "create time" value, and so
	* it's usually omitted altogether in the zip extra
	* field. Perhaps other unix systems track this.
	*
	* @return create time as java.util.Date or null.
	*/
	public Date getCreateJavaTime() {
	return zipLongToDate(createTime);
	}

	/**
	* <p>
	* Sets the modify time (seconds since epoch) of this zip entry
	* using a ZipLong object.
	* </p><p>
	* Note: the setters for flags and timestamps are decoupled.
	* Even if the timestamp is not-null, it will only be written
	* out if the corresponding bit in the flags is also set.
	* </p>
	*
	* @param l ZipLong of the modify time (seconds per epoch)
	*/
	public void setModifyTime(final ZipLong l) {
	bit0_modifyTimePresent = l != null;
	flags = (byte) (l != null ? (flags \| MODIFY_TIME_BIT)
	: (flags & ~MODIFY_TIME_BIT));
	this.modifyTime = l;
	}

	/**
	* <p>
	* Sets the access time (seconds since epoch) of this zip entry
	* using a ZipLong object
	* </p><p>
	* Note: the setters for flags and timestamps are decoupled.
	* Even if the timestamp is not-null, it will only be written
	* out if the corresponding bit in the flags is also set.
	* </p>
	*
	* @param l ZipLong of the access time (seconds per epoch)
	*/
	public void setAccessTime(final ZipLong l) {
	bit1_accessTimePresent = l != null;
	flags = (byte) (l != null ? (flags \| ACCESS_TIME_BIT)
	: (flags & ~ACCESS_TIME_BIT));
	this.accessTime = l;
	}

	/**
	* <p>
	* Sets the create time (seconds since epoch) of this zip entry
	* using a ZipLong object
	* </p><p>
	* Note: the setters for flags and timestamps are decoupled.
	* Even if the timestamp is not-null, it will only be written
	* out if the corresponding bit in the flags is also set.
	* </p>
	*
	* @param l ZipLong of the create time (seconds per epoch)
	*/
	public void setCreateTime(final ZipLong l) {
	bit2_createTimePresent = l != null;
	flags = (byte) (l != null ? (flags \| CREATE_TIME_BIT)
	: (flags & ~CREATE_TIME_BIT));
	this.createTime = l;
	}

	/**
	* <p>
	* Sets the modify time as a java.util.Date
	* of this zip entry. Supplied value is truncated to per-second
	* precision (milliseconds zeroed-out).
	* </p><p>
	* Note: the setters for flags and timestamps are decoupled.
	* Even if the timestamp is not-null, it will only be written
	* out if the corresponding bit in the flags is also set.
	* </p>
	*
	* @param d modify time as java.util.Date
	*/
	public void setModifyJavaTime(final Date d) { setModifyTime(dateToZipLong(d)); }

	/**
	* <p>
	* Sets the access time as a java.util.Date
	* of this zip entry. Supplied value is truncated to per-second
	* precision (milliseconds zeroed-out).
	* </p><p>
	* Note: the setters for flags and timestamps are decoupled.
	* Even if the timestamp is not-null, it will only be written
	* out if the corresponding bit in the flags is also set.
	* </p>
	*
	* @param d access time as java.util.Date
	*/
	public void setAccessJavaTime(final Date d) { setAccessTime(dateToZipLong(d)); }

	/**
	* <p>
	* Sets the create time as a java.util.Date
	* of this zip entry. Supplied value is truncated to per-second
	* precision (milliseconds zeroed-out).
	* </p><p>
	* Note: the setters for flags and timestamps are decoupled.
	* Even if the timestamp is not-null, it will only be written
	* out if the corresponding bit in the flags is also set.
	* </p>
	*
	* @param d create time as java.util.Date
	*/
	public void setCreateJavaTime(final Date d) { setCreateTime(dateToZipLong(d)); }

	/**
	* Utility method converts java.util.Date (milliseconds since epoch)
	* into a ZipLong (seconds since epoch).
	* <p/>
	* Also makes sure the converted ZipLong is not too big to fit
	* in 32 unsigned bits.
	*
	* @param d java.util.Date to convert to ZipLong
	* @return ZipLong
	*/
	private static ZipLong dateToZipLong(final Date d) {
	if (d == null) { return null; }

	return unixTimeToZipLong(d.getTime() / 1000);
	}

	/**
	* Returns a String representation of this class useful for
	* debugging purposes.
	*
	* @return A String representation of this class useful for
	* debugging purposes.
	*/
	@Override
	public String toString() {
	final StringBuilder buf = new StringBuilder();
	buf.append("0x5455 Zip Extra Field: Flags=");
	buf.append(Integer.toBinaryString(ZipUtil.unsignedIntToSignedByte(flags))).append(" ");
	if (bit0_modifyTimePresent && modifyTime != null) {
	final Date m = getModifyJavaTime();
	buf.append(" Modify:[").append(m).append("] ");
	}
	if (bit1_accessTimePresent && accessTime != null) {
	final Date a = getAccessJavaTime();
	buf.append(" Access:[").append(a).append("] ");
	}
	if (bit2_createTimePresent && createTime != null) {
	final Date c = getCreateJavaTime();
	buf.append(" Create:[").append(c).append("] ");
	}
	return buf.toString();
	}

	@Override
	public Object clone() throws CloneNotSupportedException {
	return super.clone();
	}

	@Override
	public boolean equals(final Object o) {
	if (o instanceof X5455_ExtendedTimestamp) {
	final X5455_ExtendedTimestamp xf = (X5455_ExtendedTimestamp) o;

	// The ZipLong==ZipLong clauses handle the cases where both are null.
	// and only last 3 bits of flags matter.
	return ((flags & 0x07) == (xf.flags & 0x07)) &&
	(modifyTime == xf.modifyTime \|\| (modifyTime != null && modifyTime.equals(xf.modifyTime))) &&
	(accessTime == xf.accessTime \|\| (accessTime != null && accessTime.equals(xf.accessTime))) &&
	(createTime == xf.createTime \|\| (createTime != null && createTime.equals(xf.createTime)));
	}
	return false;
	}

	@Override
	public int hashCode() {
	int hc = (-123 * (flags & 0x07)); // only last 3 bits of flags matter
	if (modifyTime != null) {
	hc ^= modifyTime.hashCode();
	}
	if (accessTime != null) {
	// Since accessTime is often same as modifyTime,
	// this prevents them from XOR negating each other.
	hc ^= Integer.rotateLeft(accessTime.hashCode(), 11);
	}
	if (createTime != null) {
	hc ^= Integer.rotateLeft(createTime.hashCode(), 22);
	}
	return hc;
	}

	private static Date zipLongToDate(ZipLong unixTime) {
	return unixTime != null ? new Date(unixTime.getIntValue() * 1000L) : null;
	}

	private static ZipLong unixTimeToZipLong(long l) {
	if (l < Integer.MIN_VALUE \|\| l > Integer.MAX_VALUE) {
	throw new IllegalArgumentException("X5455 timestamps must fit in a signed 32 bit integer: " + l);
	}
	return new ZipLong(l);
	}

	}