itextpdf.jar is a component in iText 5 Java library to provide core functionalities. iText Java library allows you to generate and manage PDF documents.

The Source Code files are provided at iText GitHub site.

You can compile it to generate your JAR file, using pom.xml as the build configuration file.

The source code of itextpdf-5.5.14.jar is provided below:

⏎ com/itextpdf/text/factories/RomanNumberFactory.java

/*
 *
 * This file is part of the iText (R) project.
    Copyright (c) 1998-2020 iText Group NV
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
 * ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
 * OF THIRD PARTY RIGHTS
 *
 * 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 http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * a covered work must retain the producer line in every PDF that is created
 * or manipulated using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */
package com.itextpdf.text.factories;
/**
 * This class can produce String combinations representing a roman number.
 */
public class RomanNumberFactory {
	/**
	 * Helper class for Roman Digits
	 */
	private static class RomanDigit {

		/** part of a roman number */
		public char digit;

		/** value of the roman digit */
		public int value;

		/** can the digit be used as a prefix */
		public boolean pre;

		/**
		 * Constructs a roman digit
		 * @param digit the roman digit
		 * @param value the value
		 * @param pre can it be used as a prefix
		 */
		RomanDigit(final char digit, final int value, final boolean pre) {
			this.digit = digit;
			this.value = value;
			this.pre = pre;
		}
	}

	/**
	 * Array with Roman digits.
	 */
	private static final RomanDigit[] roman = {
		new RomanDigit('m', 1000, false),
		new RomanDigit('d', 500, false),
		new RomanDigit('c', 100, true),
		new RomanDigit('l', 50, false),
		new RomanDigit('x', 10, true),
		new RomanDigit('v', 5, false),
		new RomanDigit('i', 1, true)
	};

	/**
	 * Changes an int into a lower case roman number.
	 * @param index the original number
	 * @return the roman number (lower case)
	 */
	public static final String getString(int index) {
		StringBuffer buf = new StringBuffer();

		// lower than 0 ? Add minus
		if (index < 0) {
			buf.append('-');
			index = -index;
		}

		// greater than 3000
		if (index > 3000) {
			buf.append('|');
			buf.append(getString(index / 1000));
			buf.append('|');
			// remainder
			index = index - (index / 1000) * 1000;
		}

		// number between 1 and 3000
		int pos = 0;
		while (true) {
			// loop over the array with values for m-d-c-l-x-v-i
			RomanDigit dig = roman[pos];
			// adding as many digits as we can
			while (index >= dig.value) {
				buf.append(dig.digit);
				index -= dig.value;
			}
			// we have the complete number
			if (index <= 0) {
				break;
			}
			// look for the next digit that can be used in a special way
			int j = pos;
			while (!roman[++j].pre);

			// does the special notation apply?
			if (index + roman[j].value >= dig.value) {
				buf.append(roman[j].digit).append(dig.digit);
				index -= dig.value - roman[j].value;
			}
			pos++;
		}
		return buf.toString();
	}

	/**
	 * Changes an int into a lower case roman number.
	 * @param index the original number
	 * @return the roman number (lower case)
	 */
	public static final String getLowerCaseString(final int index) {
		return getString(index);
	}

	/**
	 * Changes an int into an upper case roman number.
	 * @param index the original number
	 * @return the roman number (lower case)
	 */
	public static final String getUpperCaseString(final int index) {
		return getString(index).toUpperCase();
	}

	/**
	 * Changes an int into a roman number.
	 * @param index the original number
	 * @param lowercase true for lowercase, false otherwise
	 * @return the roman number (lower case)
	 */
	public static final String getString(final int index, final boolean lowercase) {
		if (lowercase) {
			return getLowerCaseString(index);
		}
		else {
			return getUpperCaseString(index);
		}
	}
}

⏎ com/itextpdf/text/factories/RomanNumberFactory.java

Or download all of them as a single archive file:

File name: itextpdf-5.5.14-fyi.zip
File size: 2163839 bytes
Release date: 2009-10-09
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