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/error_messages/MessageLocalization.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.error_messages;

import com.itextpdf.text.io.StreamUtil;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.util.HashMap;

/**
 * Localizes error messages. The messages are located in the package
 * com.itextpdf.text.error_messages in the form language_country.lng.
 * The internal file encoding is UTF-8 without any escape chars, it's not a
 * normal property file. See en.lng for more information on the internal format.
 * @author Paulo Soares (psoares@glintt.com)
 */
public final class MessageLocalization {
    private static HashMap<String, String> defaultLanguage = new HashMap<String, String>();
    private static HashMap<String, String> currentLanguage;
    private static final String BASE_PATH = "com/itextpdf/text/l10n/error/";

    private MessageLocalization() {
    }

    static {
        try {
            defaultLanguage = getLanguageMessages("en", null);
        } catch (Exception ex) {
            // do nothing
        }
        if (defaultLanguage == null)
            defaultLanguage = new HashMap<String, String>();
    }

    /**
     * Get a message without parameters.
     * @param key the key to the message
     * @return the message
     */
    public static String getMessage(String key) {
        return getMessage(key, true);
    }

    public static String getMessage(String key, boolean useDefaultLanguageIfMessageNotFound) {
        HashMap<String, String> cl = currentLanguage;
        String val;
        if (cl != null) {
            val = cl.get(key);
            if (val != null)
                return val;
        }

        if (useDefaultLanguageIfMessageNotFound) {
            cl = defaultLanguage;
        	val = cl.get(key);
        	if (val != null)
            	return val;
        }

        return "No message found for " + key;
    }

    /**
     * Get a message with one parameter as an primitive int. The parameter will replace the string
     * "{1}" found in the message.
     * @param key the key to the message
     * @param p1 the parameter
     * @return the message
     */
    public static String getComposedMessage(String key, int p1) {
        return getComposedMessage(key, String.valueOf(p1), null, null, null);
    }

	/**
	 * Get a message with param.length parameters or none if param is null. In
	 * the message the "{1}", "{2}" to "{lenght of param array}" are replaced
	 * with the object.toString of the param array. (with param[0] being "{1}")
	 *
	 * @since iText 5.0.6
	 * @param key
	 *            the key to the message
	 * @param param array of parameter objects, (toString is used to add it to the message)
	 * @return the message
	 */
	public static String getComposedMessage(final String key, final Object... param) {
		String msg = getMessage(key);
		if (null != param) {
			int i = 1;
			for (Object o : param) {
				if (null != o) {
					msg = msg.replace("{" + i + "}", o.toString());
				}
				i++;
			}
		}
		return msg;
	}

    /**
     * Sets the language to be used globally for the error messages. The language
     * is a two letter lowercase country designation like "en" or "pt". The country
     * is an optional two letter uppercase code like "US" or "PT".
     * @param language the language
     * @param country the country
     * @return true if the language was found, false otherwise
     * @throws IOException on error
     */
    public static boolean setLanguage(String language, String country) throws IOException {
        HashMap<String, String> lang = getLanguageMessages(language, country);
        if (lang == null)
            return false;
        currentLanguage = lang;
        return true;
    }

    /**
     * Sets the error messages directly from a Reader.
     * @param r the Reader
     * @throws IOException on error
     */
    public static void setMessages(Reader r) throws IOException {
        currentLanguage = readLanguageStream(r);
    }

    private static HashMap<String, String> getLanguageMessages(String language, String country) throws IOException {
        if (language == null)
            throw new IllegalArgumentException("The language cannot be null.");
        InputStream is = null;
        try {
            String file;
            if (country != null)
                file = language + "_" + country + ".lng";
            else
                file = language + ".lng";
            is = StreamUtil.getResourceStream(BASE_PATH + file, new MessageLocalization().getClass().getClassLoader());
            if (is != null)
                return readLanguageStream(is);
            if (country == null)
                return null;
            file = language + ".lng";
            is = StreamUtil.getResourceStream(BASE_PATH + file, new MessageLocalization().getClass().getClassLoader());
            if (is != null)
                return readLanguageStream(is);
            else
                return null;
        }
        finally {
            try {
                if (null != is){
                	is.close();
                }
            } catch (Exception exx) {
            }
            // do nothing
        }
    }

    private static HashMap<String, String> readLanguageStream(InputStream is) throws IOException {
        return readLanguageStream(new InputStreamReader(is, "UTF-8"));
    }

    private static HashMap<String, String> readLanguageStream(Reader r) throws IOException {
        HashMap<String, String> lang = new HashMap<String, String>();
        BufferedReader br = new BufferedReader(r);
        String line;
        while ((line = br.readLine()) != null) {
            int idxeq = line.indexOf('=');
            if (idxeq < 0)
                continue;
            String key = line.substring(0, idxeq).trim();
            if (key.startsWith("#"))
                continue;
            lang.put(key, line.substring(idxeq + 1));
        }
        return lang;
    }
}

⏎ com/itextpdf/text/error_messages/MessageLocalization.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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