--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/sun/util/calendar/ZoneInfo.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,783 @@
+/*
+ * Copyright 2000-2005 Sun Microsystems, Inc. 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. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package sun.util.calendar;
+
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.lang.ref.SoftReference;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.SimpleTimeZone;
+import java.util.TimeZone;
+
+/**
+ * <code>ZoneInfo</code> is an implementation subclass of {@link
+ * java.util.TimeZone TimeZone} that represents GMT offsets and
+ * daylight saving time transitions of a time zone.
+ * <p>
+ * The daylight saving time transitions are described in the {@link
+ * #transitions transitions} table consisting of a chronological
+ * sequence of transitions of GMT offset and/or daylight saving time
+ * changes. Since all transitions are represented in UTC, in theory,
+ * <code>ZoneInfo</code> can be used with any calendar systems except
+ * for the {@link #getOffset(int,int,int,int,int,int) getOffset}
+ * method that takes Gregorian calendar date fields.
+ * <p>
+ * This table covers transitions from 1900 until 2037 (as of version
+ * 1.4), Before 1900, it assumes that there was no daylight saving
+ * time and the <code>getOffset</code> methods always return the
+ * {@link #getRawOffset} value. No Local Mean Time is supported. If a
+ * specified date is beyond the transition table and this time zone is
+ * supposed to observe daylight saving time in 2037, it delegates
+ * operations to a {@link java.util.SimpleTimeZone SimpleTimeZone}
+ * object created using the daylight saving time schedule as of 2037.
+ * <p>
+ * The date items, transitions, GMT offset(s), etc. are read from a database
+ * file. See {@link ZoneInfoFile} for details.
+ * @see java.util.SimpleTimeZone
+ * @since 1.4
+ */
+
+public class ZoneInfo extends TimeZone {
+
+ private static final int UTC_TIME = 0;
+ private static final int STANDARD_TIME = 1;
+ private static final int WALL_TIME = 2;
+
+ private static final long OFFSET_MASK = 0x0fL;
+ private static final long DST_MASK = 0xf0L;
+ private static final int DST_NSHIFT = 4;
+ // this bit field is reserved for abbreviation support
+ private static final long ABBR_MASK = 0xf00L;
+ private static final int TRANSITION_NSHIFT = 12;
+
+ private static final CalendarSystem gcal = CalendarSystem.getGregorianCalendar();
+
+ /**
+ * The raw GMT offset in milliseconds between this zone and GMT.
+ * Negative offsets are to the west of Greenwich. To obtain local
+ * <em>standard</em> time, add the offset to GMT time.
+ * @serial
+ */
+ private int rawOffset;
+
+ /**
+ * Difference in milliseconds from the original GMT offset in case
+ * the raw offset value has been modified by calling {@link
+ * #setRawOffset}. The initial value is 0.
+ * @serial
+ */
+ private int rawOffsetDiff = 0;
+
+ /**
+ * A CRC32 value of all pairs of transition time (in milliseconds
+ * in <code>long</code>) in local time and its GMT offset (in
+ * seconds in <code>int</code>) in the chronological order. Byte
+ * values of each <code>long</code> and <code>int</code> are taken
+ * in the big endian order (i.e., MSB to LSB).
+ * @serial
+ */
+ private int checksum;
+
+ /**
+ * The amount of time in milliseconds saved during daylight saving
+ * time. If <code>useDaylight</code> is false, this value is 0.
+ * @serial
+ */
+ private int dstSavings;
+
+ /**
+ * This array describes transitions of GMT offsets of this time
+ * zone, including both raw offset changes and daylight saving
+ * time changes.
+ * A long integer consists of four bit fields.
+ * <ul>
+ * <li>The most significant 52-bit field represents transition
+ * time in milliseconds from Gregorian January 1 1970, 00:00:00
+ * GMT.</li>
+ * <li>The next 4-bit field is reserved and must be 0.</li>
+ * <li>The next 4-bit field is an index value to {@link #offsets
+ * offsets[]} for the amount of daylight saving at the
+ * transition. If this value is zero, it means that no daylight
+ * saving, not the index value zero.</li>
+ * <li>The least significant 4-bit field is an index value to
+ * {@link #offsets offsets[]} for <em>total</em> GMT offset at the
+ * transition.</li>
+ * </ul>
+ * If this time zone doesn't observe daylight saving time and has
+ * never changed any GMT offsets in the past, this value is null.
+ * @serial
+ */
+ private long[] transitions;
+
+ /**
+ * This array holds all unique offset values in
+ * milliseconds. Index values to this array are stored in the
+ * transitions array elements.
+ * @serial
+ */
+ private int[] offsets;
+
+ /**
+ * SimpleTimeZone parameter values. It has to have either 8 for
+ * {@link java.util.SimpleTimeZone#SimpleTimeZone(int, String,
+ * int, int , int , int , int , int , int , int , int) the
+ * 11-argument SimpleTimeZone constructor} or 10 for {@link
+ * java.util.SimpleTimeZone#SimpleTimeZone(int, String, int, int,
+ * int , int , int , int , int , int , int, int, int) the
+ * 13-argument SimpleTimeZone constructor} parameters.
+ * @serial
+ */
+ private int[] simpleTimeZoneParams;
+
+ /**
+ * True if the raw GMT offset value would change after the time
+ * zone data has been generated; false, otherwise. The default
+ * value is false.
+ * @serial
+ */
+ private boolean willGMTOffsetChange = false;
+
+ /**
+ * True if the object has been modified after its instantiation.
+ */
+ transient private boolean dirty = false;
+
+ private static final long serialVersionUID = 2653134537216586139L;
+
+ /**
+ * A constructor.
+ */
+ public ZoneInfo() {
+ }
+
+ /**
+ * A Constructor for CustomID.
+ */
+ public ZoneInfo(String ID, int rawOffset) {
+ this(ID, rawOffset, 0, 0, null, null, null, false);
+ }
+
+ /**
+ * Constructs a ZoneInfo instance.
+ *
+ * @param ID time zone name
+ * @param rawOffset GMT offset in milliseconds
+ * @param dstSavings daylight saving value in milliseconds or 0
+ * (zero) if this time zone doesn't observe Daylight Saving Time.
+ * @param checksum CRC32 value with all transitions table entry
+ * values
+ * @param transitions transition table
+ * @param offsets offset value table
+ * @param simpleTimeZoneParams parameter values for constructing
+ * SimpleTimeZone
+ * @param willGMTOffsetChange the value of willGMTOffsetChange
+ */
+ ZoneInfo(String ID,
+ int rawOffset,
+ int dstSavings,
+ int checksum,
+ long[] transitions,
+ int[] offsets,
+ int[] simpleTimeZoneParams,
+ boolean willGMTOffsetChange) {
+ setID(ID);
+ this.rawOffset = rawOffset;
+ this.dstSavings = dstSavings;
+ this.checksum = checksum;
+ this.transitions = transitions;
+ this.offsets = offsets;
+ this.simpleTimeZoneParams = simpleTimeZoneParams;
+ this.willGMTOffsetChange = willGMTOffsetChange;
+ }
+
+ /**
+ * Returns the difference in milliseconds between local time and UTC
+ * of given time, taking into account both the raw offset and the
+ * effect of daylight savings.
+ *
+ * @param date the milliseconds in UTC
+ * @return the milliseconds to add to UTC to get local wall time
+ */
+ public int getOffset(long date) {
+ return getOffsets(date, null, UTC_TIME);
+ }
+
+ public int getOffsets(long utc, int[] offsets) {
+ return getOffsets(utc, offsets, UTC_TIME);
+ }
+
+ public int getOffsetsByStandard(long standard, int[] offsets) {
+ return getOffsets(standard, offsets, STANDARD_TIME);
+ }
+
+ public int getOffsetsByWall(long wall, int[] offsets) {
+ return getOffsets(wall, offsets, WALL_TIME);
+ }
+
+ private int getOffsets(long date, int[] offsets, int type) {
+ // if dst is never observed, there is no transition.
+ if (transitions == null) {
+ int offset = getLastRawOffset();
+ if (offsets != null) {
+ offsets[0] = offset;
+ offsets[1] = 0;
+ }
+ return offset;
+ }
+
+ date -= rawOffsetDiff;
+ int index = getTransitionIndex(date, type);
+
+ // prior to the transition table, returns the raw offset.
+ // should support LMT.
+ if (index < 0) {
+ int offset = getLastRawOffset();
+ if (offsets != null) {
+ offsets[0] = offset;
+ offsets[1] = 0;
+ }
+ return offset;
+ }
+
+ if (index < transitions.length) {
+ long val = transitions[index];
+ int offset = this.offsets[(int)(val & OFFSET_MASK)] + rawOffsetDiff;
+ if (offsets != null) {
+ int dst = (int)((val >>> DST_NSHIFT) & 0xfL);
+ int save = (dst == 0) ? 0 : this.offsets[dst];
+ offsets[0] = offset - save;
+ offsets[1] = save;
+ }
+ return offset;
+ }
+
+ // beyond the transitions, delegate to SimpleTimeZone if there
+ // is a rule; otherwise, return rawOffset.
+ SimpleTimeZone tz = getLastRule();
+ if (tz != null) {
+ int rawoffset = tz.getRawOffset();
+ long msec = date;
+ if (type != UTC_TIME) {
+ msec -= rawOffset;
+ }
+ int dstoffset = tz.inDaylightTime(new Date(msec)) ? tz.getDSTSavings() : 0;
+ if (offsets != null) {
+ offsets[0] = rawoffset;
+ offsets[1] = dstoffset;
+ }
+ return rawoffset + dstoffset;
+ }
+ int offset = getLastRawOffset();
+ if (offsets != null) {
+ offsets[0] = offset;
+ offsets[1] = 0;
+ }
+ return offset;
+ }
+
+ private final int getTransitionIndex(long date, int type) {
+ int low = 0;
+ int high = transitions.length - 1;
+
+ while (low <= high) {
+ int mid = (low + high) / 2;
+ long val = transitions[mid];
+ long midVal = val >> TRANSITION_NSHIFT; // sign extended
+ if (type != UTC_TIME) {
+ midVal += offsets[(int)(val & OFFSET_MASK)]; // wall time
+ }
+ if (type == STANDARD_TIME) {
+ int dstIndex = (int)((val >>> DST_NSHIFT) & 0xfL);
+ if (dstIndex != 0) {
+ midVal -= offsets[dstIndex]; // make it standard time
+ }
+ }
+
+ if (midVal < date) {
+ low = mid + 1;
+ } else if (midVal > date) {
+ high = mid - 1;
+ } else {
+ return mid;
+ }
+ }
+
+ // if beyond the transitions, returns that index.
+ if (low >= transitions.length) {
+ return low;
+ }
+ return low - 1;
+ }
+
+ /**
+ * Returns the difference in milliseconds between local time and
+ * UTC, taking into account both the raw offset and the effect of
+ * daylight savings, for the specified date and time. This method
+ * assumes that the start and end month are distinct. This method
+ * assumes a Gregorian calendar for calculations.
+ * <p>
+ * <em>Note: In general, clients should use
+ * {@link Calendar#ZONE_OFFSET Calendar.get(ZONE_OFFSET)} +
+ * {@link Calendar#DST_OFFSET Calendar.get(DST_OFFSET)}
+ * instead of calling this method.</em>
+ *
+ * @param era The era of the given date. The value must be either
+ * GregorianCalendar.AD or GregorianCalendar.BC.
+ * @param year The year in the given date.
+ * @param month The month in the given date. Month is 0-based. e.g.,
+ * 0 for January.
+ * @param day The day-in-month of the given date.
+ * @param dayOfWeek The day-of-week of the given date.
+ * @param millis The milliseconds in day in <em>standard</em> local time.
+ * @return The milliseconds to add to UTC to get local time.
+ */
+ public int getOffset(int era, int year, int month, int day,
+ int dayOfWeek, int milliseconds) {
+ if (milliseconds < 0 || milliseconds >= AbstractCalendar.DAY_IN_MILLIS) {
+ throw new IllegalArgumentException();
+ }
+
+ if (era == java.util.GregorianCalendar.BC) { // BC
+ year = 1 - year;
+ } else if (era != java.util.GregorianCalendar.AD) {
+ throw new IllegalArgumentException();
+ }
+
+ CalendarDate date = gcal.newCalendarDate(null);
+ date.setDate(year, month + 1, day);
+ if (gcal.validate(date) == false) {
+ throw new IllegalArgumentException();
+ }
+
+ // bug-for-bug compatible argument checking
+ if (dayOfWeek < java.util.GregorianCalendar.SUNDAY
+ || dayOfWeek > java.util.GregorianCalendar.SATURDAY) {
+ throw new IllegalArgumentException();
+ }
+
+ if (transitions == null) {
+ return getLastRawOffset();
+ }
+
+ long dateInMillis = gcal.getTime(date) + milliseconds;
+ dateInMillis -= (long) rawOffset; // make it UTC
+ return getOffsets(dateInMillis, null, UTC_TIME);
+ }
+
+ /**
+ * Sets the base time zone offset from GMT. This operation
+ * modifies all the transitions of this ZoneInfo object, including
+ * historical ones, if applicable.
+ *
+ * @param offsetMillis the base time zone offset to GMT.
+ * @see getRawOffset
+ */
+ public synchronized void setRawOffset(int offsetMillis) {
+ if (offsetMillis == rawOffset + rawOffsetDiff) {
+ return;
+ }
+ rawOffsetDiff = offsetMillis - rawOffset;
+ if (lastRule != null) {
+ lastRule.setRawOffset(offsetMillis);
+ }
+ dirty = true;
+ }
+
+ /**
+ * Returns the GMT offset of the current date. This GMT offset
+ * value is not modified during Daylight Saving Time.
+ *
+ * @return the GMT offset value in milliseconds to add to UTC time
+ * to get local standard time
+ */
+ public int getRawOffset() {
+ if (!willGMTOffsetChange) {
+ return rawOffset + rawOffsetDiff;
+ }
+
+ int[] offsets = new int[2];
+ getOffsets(System.currentTimeMillis(), offsets, UTC_TIME);
+ return offsets[0];
+ }
+
+ public boolean isDirty() {
+ return dirty;
+ }
+
+ private int getLastRawOffset() {
+ return rawOffset + rawOffsetDiff;
+ }
+
+ /**
+ * Queries if this time zone uses Daylight Saving Time in the last known rule.
+ */
+ public boolean useDaylightTime() {
+ return (simpleTimeZoneParams != null);
+ }
+
+ /**
+ * Queries if the specified date is in Daylight Saving Time.
+ */
+ public boolean inDaylightTime(Date date) {
+ if (date == null) {
+ throw new NullPointerException();
+ }
+
+ if (transitions == null) {
+ return false;
+ }
+
+ long utc = date.getTime() - rawOffsetDiff;
+ int index = getTransitionIndex(utc, UTC_TIME);
+
+ // before transitions in the transition table
+ if (index < 0) {
+ return false;
+ }
+
+ // the time is in the table range.
+ if (index < transitions.length) {
+ return (transitions[index] & DST_MASK) != 0;
+ }
+
+ // beyond the transition table
+ SimpleTimeZone tz = getLastRule();
+ if (tz != null) {
+ return tz.inDaylightTime(date);
+ }
+ return false;
+ }
+
+ /**
+ * Returns the amount of time in milliseconds that the clock is advanced
+ * during daylight saving time is in effect in its last daylight saving time rule.
+ *
+ * @return the number of milliseconds the time is advanced with respect to
+ * standard time when daylight saving time is in effect.
+ */
+ public int getDSTSavings() {
+ return dstSavings;
+ }
+
+// /**
+// * @return the last year in the transition table or -1 if this
+// * time zone doesn't observe any daylight saving time.
+// */
+// public int getMaxTransitionYear() {
+// if (transitions == null) {
+// return -1;
+// }
+// long val = transitions[transitions.length - 1];
+// int offset = this.offsets[(int)(val & OFFSET_MASK)] + rawOffsetDiff;
+// val = (val >> TRANSITION_NSHIFT) + offset;
+// CalendarDate lastDate = Gregorian.getCalendarDate(val);
+// return lastDate.getYear();
+// }
+
+ /**
+ * Returns a string representation of this time zone.
+ * @return the string
+ */
+ public String toString() {
+ return getClass().getName() +
+ "[id=\"" + getID() + "\"" +
+ ",offset=" + getLastRawOffset() +
+ ",dstSavings=" + dstSavings +
+ ",useDaylight=" + useDaylightTime() +
+ ",transitions=" + ((transitions != null) ? transitions.length : 0) +
+ ",lastRule=" + (lastRule == null ? getLastRuleInstance() : lastRule) +
+ "]";
+ }
+
+ /**
+ * Gets all available IDs supported in the Java run-time.
+ *
+ * @return an array of time zone IDs.
+ */
+ public static String[] getAvailableIDs() {
+ List<String> idList = ZoneInfoFile.getZoneIDs();
+ List<String> excluded = ZoneInfoFile.getExcludedZones();
+ if (excluded != null) {
+ // List all zones from the idList and excluded lists
+ List<String> list = new ArrayList<String>(idList.size() + excluded.size());
+ list.addAll(idList);
+ list.addAll(excluded);
+ idList = list;
+ }
+ String[] ids = new String[idList.size()];
+ return idList.toArray(ids);
+ }
+
+ /**
+ * Gets all available IDs that have the same value as the
+ * specified raw GMT offset.
+ *
+ * @param rawOffset the GMT offset in milliseconds. This
+ * value should not include any daylight saving time.
+ *
+ * @return an array of time zone IDs.
+ */
+ public static String[] getAvailableIDs(int rawOffset) {
+ String[] result;
+ List<String> matched = new ArrayList<String>();
+ List<String> IDs = ZoneInfoFile.getZoneIDs();
+ int[] rawOffsets = ZoneInfoFile.getRawOffsets();
+
+ loop:
+ for (int index = 0; index < rawOffsets.length; index++) {
+ if (rawOffsets[index] == rawOffset) {
+ byte[] indices = ZoneInfoFile.getRawOffsetIndices();
+ for (int i = 0; i < indices.length; i++) {
+ if (indices[i] == index) {
+ matched.add(IDs.get(i++));
+ while (i < indices.length && indices[i] == index) {
+ matched.add(IDs.get(i++));
+ }
+ break loop;
+ }
+ }
+ }
+ }
+
+ // We need to add any zones from the excluded zone list that
+ // currently have the same GMT offset as the specified
+ // rawOffset. The zones returned by this method may not be
+ // correct as of return to the caller if any GMT offset
+ // transition is happening during this GMT offset checking...
+ List<String> excluded = ZoneInfoFile.getExcludedZones();
+ if (excluded != null) {
+ for (String id : excluded) {
+ TimeZone zi = getTimeZone(id);
+ if (zi != null && zi.getRawOffset() == rawOffset) {
+ matched.add(id);
+ }
+ }
+ }
+
+ result = new String[matched.size()];
+ matched.toArray(result);
+ return result;
+ }
+
+ /**
+ * Gets the ZoneInfo for the given ID.
+ *
+ * @param ID the ID for a ZoneInfo. See TimeZone for detail.
+ *
+ * @return the specified ZoneInfo object, or null if there is no
+ * time zone of the ID.
+ */
+ public static TimeZone getTimeZone(String ID) {
+ ZoneInfo zi = null;
+
+ zi = ZoneInfoFile.getZoneInfo(ID);
+ if (zi == null) {
+ // if we can't create an object for the ID, try aliases.
+ try {
+ Map<String, String> map = getAliasTable();
+ String alias = ID;
+ while ((alias = map.get(alias)) != null) {
+ zi = ZoneInfoFile.getZoneInfo(alias);
+ if (zi != null) {
+ zi.setID(ID);
+ zi = ZoneInfoFile.addToCache(ID, zi);
+ zi = (ZoneInfo) zi.clone();
+ break;
+ }
+ }
+ } catch (Exception e) {
+ // ignore exceptions
+ }
+ }
+ return zi;
+ }
+
+ private transient SimpleTimeZone lastRule;
+
+ /**
+ * Returns a SimpleTimeZone object representing the last GMT
+ * offset and DST schedule or null if this time zone doesn't
+ * observe DST.
+ */
+ private synchronized SimpleTimeZone getLastRule() {
+ if (lastRule == null) {
+ lastRule = getLastRuleInstance();
+ }
+ return lastRule;
+ }
+
+ /**
+ * Returns a SimpleTimeZone object that represents the last
+ * known daylight saving time rules.
+ *
+ * @return a SimpleTimeZone object or null if this time zone
+ * doesn't observe DST.
+ */
+ public SimpleTimeZone getLastRuleInstance() {
+ if (simpleTimeZoneParams == null) {
+ return null;
+ }
+ if (simpleTimeZoneParams.length == 10) {
+ return new SimpleTimeZone(getLastRawOffset(), getID(),
+ simpleTimeZoneParams[0],
+ simpleTimeZoneParams[1],
+ simpleTimeZoneParams[2],
+ simpleTimeZoneParams[3],
+ simpleTimeZoneParams[4],
+ simpleTimeZoneParams[5],
+ simpleTimeZoneParams[6],
+ simpleTimeZoneParams[7],
+ simpleTimeZoneParams[8],
+ simpleTimeZoneParams[9],
+ dstSavings);
+ }
+ return new SimpleTimeZone(getLastRawOffset(), getID(),
+ simpleTimeZoneParams[0],
+ simpleTimeZoneParams[1],
+ simpleTimeZoneParams[2],
+ simpleTimeZoneParams[3],
+ simpleTimeZoneParams[4],
+ simpleTimeZoneParams[5],
+ simpleTimeZoneParams[6],
+ simpleTimeZoneParams[7],
+ dstSavings);
+ }
+
+ /**
+ * Returns a copy of this <code>ZoneInfo</code>.
+ */
+ public Object clone() {
+ ZoneInfo zi = (ZoneInfo) super.clone();
+ zi.lastRule = null;
+ return zi;
+ }
+
+ /**
+ * Returns a hash code value calculated from the GMT offset and
+ * transitions.
+ * @return a hash code of this time zone
+ */
+ public int hashCode() {
+ return getLastRawOffset() ^ checksum;
+ }
+
+ /**
+ * Compares the equity of two ZoneInfo objects.
+ *
+ * @param obj the object to be compared with
+ * @return true if given object is same as this ZoneInfo object,
+ * false otherwise.
+ */
+ public boolean equals(Object obj) {
+ if (this == obj) {
+ return true;
+ }
+ if (!(obj instanceof ZoneInfo)) {
+ return false;
+ }
+ ZoneInfo that = (ZoneInfo) obj;
+ return (getID().equals(that.getID())
+ && (getLastRawOffset() == that.getLastRawOffset())
+ && (checksum == that.checksum));
+ }
+
+ /**
+ * Returns true if this zone has the same raw GMT offset value and
+ * transition table as another zone info. If the specified
+ * TimeZone object is not a ZoneInfo instance, this method returns
+ * true if the specified TimeZone object has the same raw GMT
+ * offset value with no daylight saving time.
+ *
+ * @param other the ZoneInfo object to be compared with
+ * @return true if the given <code>TimeZone</code> has the same
+ * GMT offset and transition information; false, otherwise.
+ */
+ public boolean hasSameRules(TimeZone other) {
+ if (this == other) {
+ return true;
+ }
+ if (other == null) {
+ return false;
+ }
+ if (!(other instanceof ZoneInfo)) {
+ if (getRawOffset() != other.getRawOffset()) {
+ return false;
+ }
+ // if both have the same raw offset and neither observes
+ // DST, they have the same rule.
+ if ((transitions == null)
+ && (useDaylightTime() == false)
+ && (other.useDaylightTime() == false)) {
+ return true;
+ }
+ return false;
+ }
+ if (getLastRawOffset() != ((ZoneInfo)other).getLastRawOffset()) {
+ return false;
+ }
+ return (checksum == ((ZoneInfo)other).checksum);
+ }
+
+ private static SoftReference<Map> aliasTable;
+
+ /**
+ * Returns a Map from alias time zone IDs to their standard
+ * time zone IDs.
+ *
+ * @return the Map that holds the mappings from alias time zone IDs
+ * to their standard time zone IDs, or null if
+ * <code>ZoneInfoMappings</code> file is not available.
+ */
+ public synchronized static Map<String, String> getAliasTable() {
+ Map<String, String> aliases = null;
+
+ SoftReference<Map> cache = aliasTable;
+ if (cache != null) {
+ aliases = cache.get();
+ if (aliases != null) {
+ return aliases;
+ }
+ }
+
+ aliases = ZoneInfoFile.getZoneAliases();
+ if (aliases != null) {
+ aliasTable = new SoftReference<Map>(aliases);
+ }
+ return aliases;
+ }
+
+ private void readObject(ObjectInputStream stream)
+ throws IOException, ClassNotFoundException {
+ stream.defaultReadObject();
+ // We don't know how this object from 1.4.x or earlier has
+ // been mutated. So it should always be marked as `dirty'.
+ dirty = true;
+ }
+}