/*
*
*
* Portions Copyright 2000-2007 Sun Microsystems, Inc. All Rights
* Reserved. Use is subject to license terms.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program 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.
*
* This program 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 at /legal/license.txt).
*
* 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 or visit www.sun.com if you need additional
* information or have any questions.
*/
/*
* (C) Copyright Taligent, Inc. 1996-1998 - All Rights Reserved
* (C) Copyright IBM Corp. 1996-1998 - All Rights Reserved
*
* The original version of this source code and documentation is copyrighted
* and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
* materials are provided under terms of a License Agreement between Taligent
* and Sun. This technology is protected by multiple US and International
* patents. This notice and attribution to Taligent may not be removed.
* Taligent is a registered trademark of Taligent, Inc.
*
*/
package java.util;
import com.sun.cldc.util.j2me.TimeZoneImpl;
/**
* <code>TimeZone</code> represents a time zone offset, and also figures
* out daylight savings.
* <p>
* Typically, you get a <code>TimeZone</code> using <code>getDefault</code>
* which creates a <code>TimeZone</code> based on the time zone where the program
* is running. For example, for a program running in Japan, <code>getDefault</code>
* creates a <code>TimeZone</code> object based on Japanese Standard Time.
* <p>
* You can also get a <code>TimeZone</code> using <code>getTimeZone</code> along
* with a time zone ID. For instance, the time zone ID for the Pacific
* Standard Time zone is "PST". So, you can get a PST <code>TimeZone</code> object
* with:
* <blockquote>
* <pre>
* TimeZone tz = TimeZone.getTimeZone("PST");
* </pre>
* </blockquote>
*
* <p> This class is a pure subset of the java.util.TimeZone class in JDK 1.3.
* <p> The only time zone ID that is required to be supported is "GMT".
* <p>
* Apart from the methods and variables being subset, the semantics of the
* getTimeZone() method may also be subset: custom IDs such as "GMT-8:00"
* are not required to be supported.
*
* @see java.util.Calendar
* @see java.util.Date
* @version CLDC 1.1 02/01/2002 (Based on JDK 1.3)
*/
public abstract class TimeZone {
private static TimeZoneImpl defaultZone = null;
private static String platform = null;
public TimeZone() {
}
/**
* Gets offset, for current date, modified in case of
* daylight savings. This is the offset to add *to* GMT to get local time.
* Gets the time zone offset, for current date, modified in case of daylight
* savings. This is the offset to add *to* GMT to get local time. Assume
* that the start and end month are distinct. This method may return incorrect
* results for rules that start at the end of February (e.g., last Sunday in
* February) or the beginning of March (e.g., March 1).
*
* @param era The era of the given date (0 = BC, 1 = AD).
* @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 offset to add *to* GMT to get local time.
* @exception IllegalArgumentException the era, month, day,
* dayOfWeek, or millis parameters are out of range
*/
public abstract int getOffset(int era, int year, int month, int day,
int dayOfWeek, int millis);
/**
* Gets the GMT offset for this time zone.
*
* @return the GMT offset for this time zone.
*/
public abstract int getRawOffset();
/**
* Queries if this time zone uses Daylight Savings Time.
*
* @return if this time zone uses Daylight Savings Time.
*/
public abstract boolean useDaylightTime();
/**
* Gets the ID of this time zone.
* @return the ID of this time zone.
*/
public String getID() {
return null;
}
/**
* Gets the <code>TimeZone</code> for the given ID.
* @param ID the ID for a <code>TimeZone</code>, either an abbreviation such as
* "GMT", or a full name such as "America/Los_Angeles".
* <p> The only time zone ID that is required to be supported is "GMT".
*
* @return the specified TimeZone, or the GMT zone if the given ID cannot be
* understood.
*/
public static synchronized TimeZone getTimeZone(String ID) {
if (ID == null) {
throw new NullPointerException();
}
getDefault();
TimeZone tz = defaultZone.getInstance(ID);
if (tz == null) {
tz = defaultZone.getInstance("GMT");
}
return tz;
}
/**
* Gets the default <code>TimeZone</code> for this host.
* The source of the default <code>TimeZone</code>
* may vary with implementation.
* @return a default <code>TimeZone</code>.
*/
/* <p>
* The following is information for implementers. Applications
* should not need to be aware of this or rely on it, because
* each implementation may do it differently:
* <p>
* The TimeZone class will look up a time zone implementation
* class at runtime. The class name will take the form:
* <p>
* <code>{classRoot}.util.{platform}.TimeZoneImpl</code>
* <p>
* To simplify things, we use a hard-coded path name here.
* Actual location of the implementation class may vary
* from one implementation to another.
*/
public static synchronized TimeZone getDefault() {
if ( defaultZone == null ) {
try {
Class clazz = Class.forName("com.sun.cldc.util.j2me.TimeZoneImpl");
// Construct a new TimeZoneImpl instance
defaultZone = (TimeZoneImpl)clazz.newInstance();
defaultZone = (TimeZoneImpl)defaultZone.getInstance(null);
}
catch (Exception x) {}
}
return defaultZone;
}
/**
* Gets all the available IDs supported.
* @return an array of IDs.
*/
public static String[] getAvailableIDs() {
getDefault();
return defaultZone.getIDs();
}
}
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