/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 2007-2010 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*
*
* This file incorporates work covered by the following copyright and
* permission notice:
*
* Copyright 2004 The Apache Software Foundation
*
* Licensed 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 com.sun.grizzly.util.http;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.util.TimeZone;
import java.util.concurrent.ConcurrentHashMap;
/**
* Utility class to generate HTTP dates.
*
* @author Gustav Trede
* @author Remy Maucherat
*/
public final class FastHttpDateFormat {
protected static final int CACHE_SIZE = 1000;
protected static final TimeZone GMT_TIME_ZONE = TimeZone.getTimeZone("GMT");
/**
* HTTP date format.
*/
protected static final ThreadLocal<SimpleDateFormat> FORMAT =
new ThreadLocal<SimpleDateFormat>() {
@Override
protected SimpleDateFormat initialValue() {
SimpleDateFormat f =
new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss zzz", Locale.US);
f.setTimeZone(GMT_TIME_ZONE);
return f;
}
};
protected final static TimeZone gmtZone = TimeZone.getTimeZone("GMT");
/**
* ThreadLocal for the set of SimpleDateFormat formats to use in getDateHeader().
* GMT timezone - all HTTP dates are on GMT
*/
protected static final ThreadLocal FORMATS =
new ThreadLocal() {
@Override
protected Object initialValue() {
SimpleDateFormat[] f = new SimpleDateFormat[3];
f[0] = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss zzz",
Locale.US);
f[0].setTimeZone(GMT_TIME_ZONE);
f[1] = new SimpleDateFormat("EEEEEE, dd-MMM-yy HH:mm:ss zzz",
Locale.US);
f[1].setTimeZone(GMT_TIME_ZONE);
f[2] = new SimpleDateFormat("EEE MMMM d HH:mm:ss yyyy",
Locale.US);
f[2].setTimeZone(GMT_TIME_ZONE);
return f;
}
};
/**
* Instant on which the currentDate object was generated.
*/
protected static volatile long nextGeneration;
/**
* Current formatted date.
*/
protected static volatile String currentDate;
/**
* Formatter cache.
*/
protected static final ConcurrentHashMap<Long, String> formatCache =
new ConcurrentHashMap<Long, String>(CACHE_SIZE,0.75f,64);
/**
* Parser cache.
*/
protected static final ConcurrentHashMap<String, Long> parseCache =
new ConcurrentHashMap<String, Long>(CACHE_SIZE,0.75f,64);
// --------------------------------------------------------- Public Methods
/**
* Get the current date in HTTP format.
*/
public static final String getCurrentDate() {
long now = System.currentTimeMillis();
if (now > nextGeneration) {
synchronized(FORMAT) {
if (now > nextGeneration) {
nextGeneration = now + 1000;
currentDate = FORMAT.get().format(new Date(now));
}
}
}
return currentDate;
}
/**
* Get the HTTP format of the specified date.<br>
* http spec only requre second precision http://tools.ietf.org/html/rfc2616#page-20 <br>
* therefore we dont use the millisecond precision , but second .
* truncation is done in the same way for second precision in SimpleDateFormat:<br>
* (999 millisec. = 0 sec.)
* @param timestamp in millisec
* @param the formater used if cache value was not found
*/
public static final String formatDate(long value, DateFormat threadLocalformat) {
// truncating to second precision
// this way we optimally use the cache to only store needed http values
value = (value/1000)*1000;
Long longValue = value;
String cachedDate = formatCache.get(longValue);
if (cachedDate != null){
return cachedDate;
}
String newDate = null;
Date dateValue = new Date(value);
if (threadLocalformat != null) {
newDate = threadLocalformat.format(dateValue);
} else {
newDate = FORMAT.get().format(dateValue);
}
updateFormatCache(longValue, newDate);
return newDate;
}
/**
* Try to parse the given date as a HTTP date.
*/
public static final long parseDate(final String value,
DateFormat[] threadLocalformats) {
Long cachedDate = parseCache.get(value);
if (cachedDate != null){
return cachedDate;
}
long date ;
if (threadLocalformats != null) {
date = internalParseDate(value, threadLocalformats);
} else {
date = internalParseDate(value, (SimpleDateFormat[])FORMATS.get());
}
if (date != -1) {
updateParseCache(value, date);
}
return date;
}
/**
* Parse date with given formatters.
*/
private static final long internalParseDate (String value, DateFormat[] formats){
for (int i = 0;i < formats.length; i++) {
try {
return formats[i].parse(value).getTime();
} catch (ParseException e) {
return -1;
}
}
return -1;
}
/**
* Update cache.
*/
private static void updateFormatCache(Long key, String value) {
if (value == null) {
return;
}
if (formatCache.size() > CACHE_SIZE) {
formatCache.clear();
}
formatCache.put(key, value);
}
/**
* Update cache.
*/
private static void updateParseCache(String key, Long value) {
if (parseCache.size() > CACHE_SIZE) {
parseCache.clear();
}
parseCache.put(key, value);
}
}