EmailAddress.java

/*
 * Copyright (c) 2006-2009 by Dirk Riehle, http://dirkriehle.com
 *
 * This file is part of the Wahlzeit photo rating application.
 *
 * 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
 * <http://www.gnu.org/licenses/>.
 */

package org.wahlzeit.services;

import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;

/**
 * An email address provides a simple email address representation.
 * It is a value object and implemented as immutable.
 */
public class EmailAddress implements Serializable {

	/**
	 *
	 */
	protected static final Map<String, EmailAddress> instances = new HashMap<String, EmailAddress>();

	/**
	 *
	 */
	public static final EmailAddress EMPTY = doGetFromString(""); // after map initialization...
	/**
	 *
	 */
	protected String value;

	private EmailAddress() {
		// for Objectify to load
	}

	/**
	 *
	 */
	protected EmailAddress(String myAddress) {
		value = myAddress;
	}

	/**
	 *
	 */
	public static EmailAddress getFromString(String myValue) {
		return doGetFromString(myValue);
	}

	/**
	 *
	 */
	protected static EmailAddress doGetFromString(String myValue) {
		EmailAddress result = instances.get(myValue);
		if (result == null) {
			synchronized (instances) {
				result = instances.get(myValue);
				if (result == null) {
					result = new EmailAddress(myValue);
					instances.put(myValue, result);
				}
			}
		}

		return result;
	}

	/**
	 *
	 */
	public String asString() {
		return value;
	}

	/**
	 *
	 */
	public InternetAddress asInternetAddress() {
		InternetAddress result = null;

		try {
			result = new InternetAddress(value);
		} catch (AddressException ex) {
			// should not happen
		}

		return result;
	}

	/**
	 * @methodtype boolean-query
	 */
	public boolean isEqual(EmailAddress emailAddress) {
		return this == emailAddress;
	}

	/**
	 *
	 */

	public boolean isValid() {
		return !isEmpty();
	}

	/**
	 *
	 */
	public boolean isEmpty() {
		return this == EMPTY;
	}

}