PdfDate.java
/*
This file is part of the iText (R) project.
Copyright (c) 1998-2025 Apryse Group NV
Authors: Apryse Software.
This program is offered under a commercial and under the AGPL license.
For commercial licensing, contact us at https://itextpdf.com/sales. For AGPL licensing, see below.
AGPL licensing:
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
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 Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
package com.itextpdf.kernel.pdf;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.SimpleTimeZone;
/**
* {@code PdfDate} is the PDF date object.
* <p>
* PDF defines a standard date format. The PDF date format closely follows the format
* defined by the international standard ASN.1 (Abstract Syntax Notation One, defined
* in CCITT X.208 or ISO/IEC 8824). A date is a {@code PdfString} of the form:
* <p>
* {@code (D:YYYYMMDDHHmmSSOHH'mm') }
* <p>
* See also ISO-320001 7.9.4, "Dates".
*
* @see PdfString
* @see java.util.GregorianCalendar
*/
public class PdfDate extends PdfObjectWrapper<PdfString> {
private static final int[] DATE_SPACE = {Calendar.YEAR, 4, 0, Calendar.MONTH, 2, -1, Calendar.DAY_OF_MONTH, 2, 0,
Calendar.HOUR_OF_DAY, 2, 0, Calendar.MINUTE, 2, 0, Calendar.SECOND, 2, 0};
/**
* Constructs a {@code PdfDate}-object.
*
* @param d the date that has to be turned into a {@code PdfDate} >-object
*/
public PdfDate(Calendar d) {
super(new PdfString(generateStringByCalendar(d)));
}
/**
* Constructs a {@code PdfDate}-object, representing the current day and time.
*/
public PdfDate() {
this(new GregorianCalendar());
}
/**
* Gives the W3C format of the PdfDate.
* @return a formatted date
*/
public String getW3CDate() {
return getW3CDate(getPdfObject().getValue());
}
/**
* Gives the W3C format of the {@code PdfDate}.
* @param d the date in the format D:YYYYMMDDHHmmSSOHH'mm'
* @return a formatted date
*/
public static String getW3CDate(String d) {
if (d.startsWith("D:"))
d = d.substring(2);
StringBuilder sb = new StringBuilder();
if (d.length() < 4)
return "0000";
//year
sb.append(d.substring(0, 4));
d = d.substring(4);
if (d.length() < 2)
return sb.toString();
//month
sb.append('-').append(d.substring(0, 2));
d = d.substring(2);
if (d.length() < 2)
return sb.toString();
//day
sb.append('-').append(d.substring(0, 2));
d = d.substring(2);
if (d.length() < 2)
return sb.toString();
//hour
sb.append('T').append(d.substring(0, 2));
d = d.substring(2);
if (d.length() < 2) {
sb.append(":00Z");
return sb.toString();
}
//minute
sb.append(':').append(d.substring(0, 2));
d = d.substring(2);
if (d.length() < 2) {
sb.append('Z');
return sb.toString();
}
//second
sb.append(':').append(d.substring(0, 2));
d = d.substring(2);
if (d.startsWith("-") || d.startsWith("+")) {
String sign = d.substring(0, 1);
d = d.substring(1);
if (d.length() >= 2) {
String h = d.substring(0, 2);
String m = "00";
if (d.length() > 2) {
d = d.substring(3);
if (d.length() >= 2)
m = d.substring(0, 2);
}
sb.append(sign).append(h).append(':').append(m);
return sb.toString();
}
}
sb.append('Z');
return sb.toString();
}
/**
* Converts a PDF string representing a date into a {@code Calendar}.
* @param s the PDF string representing a date
* @return a {@code Calendar} representing the date or {@code null} if the string
* was not a date
*/
public static Calendar decode(String s) {
try {
if (s.startsWith("D:"))
s = s.substring(2);
GregorianCalendar calendar;
int slen = s.length();
int idx = s.indexOf('Z');
if (idx >= 0) {
slen = idx;
calendar = new GregorianCalendar(new SimpleTimeZone(0, "ZPDF"));
}
else {
int sign = 1;
idx = s.indexOf('+');
if (idx < 0) {
idx = s.indexOf('-');
if (idx >= 0)
sign = -1;
}
if (idx < 0)
calendar = new GregorianCalendar();
else {
int offset = Integer.parseInt(s.substring(idx + 1, idx + 3)) * 60;
if (idx + 5 < s.length())
offset += Integer.parseInt(s.substring(idx + 4, idx + 6));
calendar = new GregorianCalendar(new SimpleTimeZone(offset * sign * 60000, "ZPDF"));
slen = idx;
}
}
calendar.clear();
idx = 0;
for (int k = 0; k < DATE_SPACE.length; k += 3) {
if (idx >= slen)
break;
calendar.set(DATE_SPACE[k], Integer.parseInt(s.substring(idx, idx + DATE_SPACE[k + 1])) + DATE_SPACE[k + 2]);
idx += DATE_SPACE[k + 1];
}
return calendar;
}
catch (Exception e) {
return null;
}
}
@Override
protected boolean isWrappedObjectMustBeIndirect() {
return false;
}
private static String generateStringByCalendar(Calendar d) {
StringBuilder date = new StringBuilder("D:");
date.append(setLength(d.get(Calendar.YEAR), 4));
date.append(setLength(d.get(Calendar.MONTH) + 1, 2));
date.append(setLength(d.get(Calendar.DATE), 2));
date.append(setLength(d.get(Calendar.HOUR_OF_DAY), 2));
date.append(setLength(d.get(Calendar.MINUTE), 2));
date.append(setLength(d.get(Calendar.SECOND), 2));
int timezone = (d.get(Calendar.ZONE_OFFSET) + d.get(Calendar.DST_OFFSET)) / (60 * 60 * 1000);
if (timezone == 0) {
date.append('Z');
}
else if (timezone < 0) {
date.append('-');
timezone = -timezone;
}
else {
date.append('+');
}
if (timezone != 0) {
date.append(setLength(timezone, 2)).append('\'');
int zone = Math.abs((d.get(Calendar.ZONE_OFFSET) + d.get(Calendar.DST_OFFSET)) / (60 * 1000)) - (timezone * 60);
date.append(setLength(zone, 2)).append('\'');
}
return date.toString();
}
/**
* Adds a number of leading zeros to a given {@code String} in order to get a {@code String}
* of a certain length.
*
* @param i a given number
* @param length the length of the resulting {@code String}
* @return the resulting {@code String}
*/
private static String setLength(int i, int length) {
// 1.3-1.4 problem fixed by Finn Bock
StringBuilder tmp = new StringBuilder();
tmp.append(i);
while (tmp.length() < length) {
tmp.insert(0, "0");
}
tmp.setLength(length);
return tmp.toString();
}
}