/**
* Copyright (c) 2012, Ben Fortuna
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* o Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* o Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* o Neither the name of Ben Fortuna nor the names of any other contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package net.fortuna.ical4j.model;
import java.io.IOException;
import java.net.URL;
import java.util.Map;
import java.util.Properties;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import net.fortuna.ical4j.data.CalendarBuilder;
import net.fortuna.ical4j.data.ParserException;
import net.fortuna.ical4j.model.component.VTimeZone;
import net.fortuna.ical4j.model.property.TzUrl;
import net.fortuna.ical4j.util.CompatibilityHints;
import net.fortuna.ical4j.util.Configurator;
import net.fortuna.ical4j.util.ResourceLoader;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import edu.emory.mathcs.backport.java.util.concurrent.ConcurrentHashMap;
/**
* $Id$
*
* Created on 18/09/2005
*
* The default implementation of a <code>TimeZoneRegistry</code>. This implementation will search the classpath for
* applicable VTimeZone definitions used to back the provided TimeZone instances.
* @author Ben Fortuna
*/
public class TimeZoneRegistryImpl implements TimeZoneRegistry {
private static final String DEFAULT_RESOURCE_PREFIX = "zoneinfo/";
private static final Pattern TZ_ID_SUFFIX = Pattern.compile("(?<=/)[^/]*/[^/]*$");
private static final String UPDATE_ENABLED = "net.fortuna.ical4j.timezone.update.enabled";
private static final Map DEFAULT_TIMEZONES = new ConcurrentHashMap();
private static final Properties ALIASES = new Properties();
static {
try {
//ALIASES.load(ResourceLoader.getResourceAsStream("net/fortuna/ical4j/model/tz.alias"));
ALIASES.load(TimeZoneRegistryImpl.class.getResourceAsStream("tz.alias"));
}
catch (IOException ioe) {
LogFactory.getLog(TimeZoneRegistryImpl.class).warn(
"Error loading timezone aliases: " + ioe.getMessage());
}
}
private Map timezones;
private String resourcePrefix;
/**
* Default constructor.
*/
public TimeZoneRegistryImpl() {
this(DEFAULT_RESOURCE_PREFIX);
}
/**
* Creates a new instance using the specified resource prefix.
* @param resourcePrefix a prefix prepended to classpath resource lookups for default timezones
*/
public TimeZoneRegistryImpl(final String resourcePrefix) {
this.resourcePrefix = resourcePrefix;
timezones = new ConcurrentHashMap();
}
/**
* {@inheritDoc}
*/
public final void register(final TimeZone timezone) {
// for now we only apply updates to included definitions by default..
register(timezone, false);
}
/**
* {@inheritDoc}
*/
public final void register(final TimeZone timezone, boolean update) {
if (update) {
// load any available updates for the timezone..
timezones.put(timezone.getID(), new TimeZone(updateDefinition(timezone.getVTimeZone())));
}
else {
timezones.put(timezone.getID(), timezone);
}
}
/**
* {@inheritDoc}
*/
public final void clear() {
timezones.clear();
}
/**
* {@inheritDoc}
*/
public final TimeZone getTimeZone(final String id) {
TimeZone timezone = (TimeZone) timezones.get(id);
if (timezone == null) {
timezone = (TimeZone) DEFAULT_TIMEZONES.get(id);
if (timezone == null) {
// if timezone not found with identifier, try loading an alias..
final String alias = ALIASES.getProperty(id);
if (alias != null) {
return getTimeZone(alias);
}
else {
synchronized (DEFAULT_TIMEZONES) {
// check again as it may be loaded now..
timezone = (TimeZone) DEFAULT_TIMEZONES.get(id);
if (timezone == null) {
try {
final VTimeZone vTimeZone = loadVTimeZone(id);
if (vTimeZone != null) {
// XXX: temporary kludge..
// ((TzId) vTimeZone.getProperties().getProperty(Property.TZID)).setValue(id);
timezone = new TimeZone(vTimeZone);
DEFAULT_TIMEZONES.put(timezone.getID(), timezone);
}
else if (CompatibilityHints.isHintEnabled(CompatibilityHints.KEY_RELAXED_PARSING)) {
// strip global part of id and match on default tz..
Matcher matcher = TZ_ID_SUFFIX.matcher(id);
if (matcher.find()) {
return getTimeZone(matcher.group());
}
}
}
catch (Exception e) {
Log log = LogFactory.getLog(TimeZoneRegistryImpl.class);
log.warn("Error occurred loading VTimeZone", e);
}
}
}
}
}
}
return timezone;
}
/**
* Loads an existing VTimeZone from the classpath corresponding to the specified Java timezone.
*/
private VTimeZone loadVTimeZone(final String id) throws IOException, ParserException {
//final URL resource = ResourceLoader.getResource(resourcePrefix + id + ".ics");
final URL resource = TimeZoneRegistryImpl.class.getClassLoader().getResource(resourcePrefix + id + ".ics");
if (resource != null) {
final CalendarBuilder builder = new CalendarBuilder();
final Calendar calendar = builder.build(resource.openStream());
final VTimeZone vTimeZone = (VTimeZone) calendar.getComponent(Component.VTIMEZONE);
// load any available updates for the timezone.. can be explicility disabled via configuration
if (!"false".equals(Configurator.getProperty(UPDATE_ENABLED))) {
return updateDefinition(vTimeZone);
}
return vTimeZone;
}
return null;
}
/**
* @param vTimeZone
* @return
*/
private VTimeZone updateDefinition(VTimeZone vTimeZone) {
final TzUrl tzUrl = vTimeZone.getTimeZoneUrl();
if (tzUrl != null) {
try {
final CalendarBuilder builder = new CalendarBuilder();
final Calendar calendar = builder.build(tzUrl.getUri().toURL().openStream());
final VTimeZone updatedVTimeZone = (VTimeZone) calendar.getComponent(Component.VTIMEZONE);
if (updatedVTimeZone != null) {
return updatedVTimeZone;
}
}
catch (Exception e) {
Log log = LogFactory.getLog(TimeZoneRegistryImpl.class);
log.warn("Unable to retrieve updates for timezone: " + vTimeZone.getTimeZoneId().getValue(), e);
}
}
return vTimeZone;
}
}