DateOfBirthDataConvertor.java

/*
 * Commons eID Project.
 * Copyright (C) 2008-2013 FedICT.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License version
 * 3.0 as published by the Free Software Foundation.
 *
 * This software 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, see 
 * http://www.gnu.org/licenses/.
 */

package be.fedict.commons.eid.consumer.tlv;

import java.io.UnsupportedEncodingException;
import java.util.GregorianCalendar;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Convertor for eID date of birth field.
 * 
 * @author Frank Cornelis
 * 
 */
public class DateOfBirthDataConvertor
		implements
			DataConvertor<GregorianCalendar> {

	private static final Log LOG = LogFactory
			.getLog(DateOfBirthDataConvertor.class);

	@Override
	public GregorianCalendar convert(final byte[] value)
			throws DataConvertorException {
		String dateOfBirthStr;
		try {
			dateOfBirthStr = new String(value, "UTF-8").trim();
		} catch (final UnsupportedEncodingException uex) {
			throw new DataConvertorException("UTF-8 not supported");
		}
		LOG.debug("\"" + dateOfBirthStr + "\"");
		/*
		 * First try to detect the German format as there are cases in which a
		 * German format contains both dots and spaces.
		 */
		int spaceIdx = dateOfBirthStr.indexOf('.');
		if (-1 == spaceIdx) {
			spaceIdx = dateOfBirthStr.indexOf(' ');
		}

		if (spaceIdx > 0) {
			final String dayStr = dateOfBirthStr.substring(0, spaceIdx);
			LOG.debug("day: \"" + dayStr + "\"");
			final int day = Integer.parseInt(dayStr);
			String monthStr = dateOfBirthStr.substring(spaceIdx + 1,
					dateOfBirthStr.length() - 4 - 1);
			if (monthStr.endsWith(".")) {
				monthStr = monthStr.substring(0, monthStr.length() - 1);
			}
			LOG.debug("month: \"" + monthStr + "\"");
			final String yearStr = dateOfBirthStr.substring(dateOfBirthStr
					.length() - 4);
			LOG.debug("year: \"" + yearStr + "\"");
			final int year = Integer.parseInt(yearStr);
			final int month = toMonth(monthStr);
			return new GregorianCalendar(year, month, day);
		}

		if (dateOfBirthStr.length() == 4) {
			/*
			 * "case II2b2". Only a birth year is given
			 * 
			 * there's no way of representing "missing" fields via
			 * GregorianCalendar, so we set Jan 1st
			 */
			return new GregorianCalendar(Integer.parseInt(dateOfBirthStr), 0, 1);
		}

		throw new DataConvertorException("Unsupported Birth Date Format ["
				+ dateOfBirthStr + "]");
	}

	private static final String[][] MONTHS = new String[][]{
			new String[]{"JAN"}, new String[]{"FEV", "FEB"},
			new String[]{"MARS", "MAAR", "MÄR"}, new String[]{"AVR", "APR"},
			new String[]{"MAI", "MEI"}, new String[]{"JUIN", "JUN"},
			new String[]{"JUIL", "JUL"}, new String[]{"AOUT", "AUG"},
			new String[]{"SEPT", "SEP"}, new String[]{"OCT", "OKT"},
			new String[]{"NOV"}, new String[]{"DEC", "DEZ"}};

	private int toMonth(String monthStr) throws DataConvertorException {
		monthStr = monthStr.trim();
		for (int monthIdx = 0; monthIdx < MONTHS.length; monthIdx++) {
			final String[] monthNames = MONTHS[monthIdx];
			for (String monthName : monthNames) {
				if (monthName.equals(monthStr)) {
					return monthIdx;
				}
			}
		}
		throw new DataConvertorException("unknown month: " + monthStr);
	}
}