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/*
* Copyright 1999,2004 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.
*/
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;
/**
* ISO 8601 date parsing utility. Designed for parsing the ISO subset used in
* Dublin Core, RSS 1.0, and Atom.
*
* @author <a href="mailto:burton@apache.org">Kevin A. Burton (burtonator)</a>
* @version $Id: ISO8601DateParser.java,v 1.2 2005/06/03 20:25:29 snoopdave Exp $
*/
public class ISO8601DateParser {
// 2004-06-14T19:GMT20:30Z
// 2004-06-20T06:GMT22:01Z
// http://www.cl.cam.ac.uk/~mgk25/iso-time.html
//
// http://www.intertwingly.net/wiki/pie/DateTime
//
// http://www.w3.org/TR/NOTE-datetime
//
// Different standards may need different levels of granularity in the date and
// time, so this profile defines six levels. Standards that reference this
// profile should specify one or more of these granularities. If a given
// standard allows more than one granularity, it should specify the meaning of
// the dates and times with reduced precision, for example, the result of
// comparing two dates with different precisions.
// The formats are as follows. Exactly the components shown here must be
// present, with exactly this punctuation. Note that the "T" appears literally
// in the string, to indicate the beginning of the time element, as specified in
// ISO 8601.
// Year:
// YYYY (eg 1997)
// Year and month:
// YYYY-MM (eg 1997-07)
// Complete date:
// YYYY-MM-DD (eg 1997-07-16)
// Complete date plus hours and minutes:
// YYYY-MM-DDThh:mmTZD (eg 1997-07-16T19:20+01:00)
// Complete date plus hours, minutes and seconds:
// YYYY-MM-DDThh:mm:ssTZD (eg 1997-07-16T19:20:30+01:00)
// Complete date plus hours, minutes, seconds and a decimal fraction of a
// second
// YYYY-MM-DDThh:mm:ss.sTZD (eg 1997-07-16T19:20:30.45+01:00)
// where:
// YYYY = four-digit year
// MM = two-digit month (01=January, etc.)
// DD = two-digit day of month (01 through 31)
// hh = two digits of hour (00 through 23) (am/pm NOT allowed)
// mm = two digits of minute (00 through 59)
// ss = two digits of second (00 through 59)
// s = one or more digits representing a decimal fraction of a second
// TZD = time zone designator (Z or +hh:mm or -hh:mm)
public static Date parse( String input ) throws java.text.ParseException {
//NOTE: SimpleDateFormat uses GMT[-+]hh:mm for the TZ which breaks
//things a bit. Before we go on we have to repair this.
SimpleDateFormat df = new SimpleDateFormat( "yyyy-MM-dd'T'HH:mm:ssz" );
//this is zero time so we need to add that TZ indicator for
if ( input.endsWith( "Z" ) ) {
input = input.substring( 0, input.length() - 1) + "GMT-00:00";
} else {
int inset = 6;
String s0 = input.substring( 0, input.length() - inset );
String s1 = input.substring( input.length() - inset, input.length() );
input = s0 + "GMT" + s1;
}
return df.parse( input );
}
public static String toString( Date date ) {
SimpleDateFormat df = new SimpleDateFormat( "yyyy-MM-dd'T'HH:mm:ssz" );
TimeZone tz = TimeZone.getTimeZone( "UTC" );
df.setTimeZone( tz );
String output = df.format( date );
int inset0 = 9;
int inset1 = 6;
String s0 = output.substring( 0, output.length() - inset0 );
String s1 = output.substring( output.length() - inset1, output.length() );
String result = s0 + s1;
result = result.replaceAll( "UTC", "+00:00" );
return result;
}
}
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