JodaBaseJsonSerializer.java

/* ==================================================================
 * JodaBaseJsonSerializer.java - Mar 20, 2013 5:50:24 PM
 * 
 * Copyright 2007-2013 SolarNetwork.net Dev Team
 * 
 * This program is free software; you can redistribute it and/or 
 * modify it under the terms of the GNU General Public License as 
 * published by the Free Software Foundation; either version 2 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 
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License 
 * along with this program; if not, write to the Free Software 
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 
 * 02111-1307 USA
 * ==================================================================
 */

package net.solarnetwork.util;

import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;
import org.joda.time.DateTimeZone;
import org.joda.time.ReadableInstant;
import org.joda.time.ReadablePartial;
import org.joda.time.format.DateTimeFormat;
import org.joda.time.format.DateTimeFormatter;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.ser.std.StdScalarSerializer;

/**
 * Abstract {@link JsonSerializer} class for converting Joda objects into simple
 * strings.
 * 
 * @author matt
 * @version 1.1
 */
public abstract class JodaBaseJsonSerializer<T> extends StdScalarSerializer<T> {

	private static final long serialVersionUID = -7898014390210021054L;

	private final DateTimeFormatter formatter;

	/**
	 * Construct from a String date pattern.
	 * 
	 * @param clazz
	 *        the class type
	 * @param pattern
	 *        the Joda date format pattern
	 */
	public JodaBaseJsonSerializer(Class<T> clazz, String pattern) {
		this(clazz, pattern, null);
	}

	/**
	 * Construct from a String date pattern.
	 * 
	 * @param clazz
	 *        the class type
	 * @param pattern
	 *        the Joda date format pattern
	 * @param timeZone
	 *        the time zone to format in
	 */
	public JodaBaseJsonSerializer(Class<T> clazz, String pattern, TimeZone timeZone) {
		super(clazz);
		if ( timeZone != null ) {
			formatter = DateTimeFormat.forPattern(pattern).withZone(DateTimeZone.forTimeZone(timeZone));
		} else {
			formatter = DateTimeFormat.forPattern(pattern);
		}
	}

	/**
	 * Serialize a JodaTime object into a string using the configured formatter.
	 * 
	 * @param propertyValue
	 *        the JodaTime object
	 * @return the String, or <em>null</em> if {@code propertyValue} is
	 *         <em>null</em>
	 * @throws IllegalArgumentException
	 *         if {@code propertyValue} is not a supported JodaTime object
	 */
	public final String serializeWithFormatter(Object propertyValue) {
		if ( propertyValue == null ) {
			return null;
		} else if ( propertyValue instanceof ReadableInstant ) {
			return formatter.print((ReadableInstant) propertyValue);
		} else if ( propertyValue instanceof ReadablePartial ) {
			return formatter.print((ReadablePartial) propertyValue);
		} else if ( propertyValue instanceof Date ) {
			return formatter.print(((Date) propertyValue).getTime());
		} else if ( propertyValue instanceof Calendar ) {
			return formatter.print(((Calendar) propertyValue).getTimeInMillis());
		}
		throw new IllegalArgumentException(
				"Unsupported date object [" + propertyValue.getClass() + "]: " + propertyValue);
	}

}