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Artifact for event handling purposes according to the observer (observable) pattern.
There is a newer version: 1.1.1
// /////////////////////////////////////////////////////////////////////////////
// REFCODES.ORG
// =============================================================================
// This code is copyright (c) by Siegfried Steiner, Munich, Germany and licensed
// under the following (see "http://en.wikipedia.org/wiki/Multi-licensing")
// licenses:
// =============================================================================
// GNU General Public License, v3.0 ("http://www.gnu.org/licenses/gpl-3.0.html")
// together with the GPL linking exception applied; as being applied by the GNU
// Classpath ("http://www.gnu.org/software/classpath/license.html")
// =============================================================================
// Apache License, v2.0 ("http://www.apache.org/licenses/LICENSE-2.0")
// =============================================================================
// Please contact the copyright holding author(s) of the software artifacts in
// question for licensing issues not being covered by the above listed licenses,
// also regarding commercial licensing models or regarding the compatibility
// with other open source licenses.
// /////////////////////////////////////////////////////////////////////////////

package org.refcodes.observer.impls;

import org.refcodes.observer.ActionEvent;
import org.refcodes.observer.EventMatcherByDeclaration;
import org.refcodes.observer.EventMetaData;
import org.refcodes.observer.MetaDataEvent;
import org.refcodes.observer.Observer;
import org.refcodes.runtime.RuntimeUtility;

/**
 * Ready to use {@link ActionEvent} storing a defined set of
 * {@link EventMetaData}.
 * 
 * TIPP: In order to distinguish {@link MetaDataEventImpl} instances from each
 * other, create an actions enumeration, enumerating the various event actions
 * you support. Pass the actual action you intend to notify upon to the
 * according constructor, as an {@link Observer} you may use the declarative
 * method {@link EventMatcherByDeclaration#actionEqualWith(Object)} to test
 * whether your action was notified (or a simple switch case statement).
 * 
 * @param  The type of the source in question.
 */
public class MetaDataEventImpl extends AbstractEvent implements MetaDataEvent {

	// /////////////////////////////////////////////////////////////////////////
	// VARIABLES:
	// /////////////////////////////////////////////////////////////////////////

	private EventMetaData _eventMetaData;

	// /////////////////////////////////////////////////////////////////////////
	// CONSTRUCTORS:
	// /////////////////////////////////////////////////////////////////////////

	/**
	 * Constructs an event with the given meta Data.
	 * 
	 * @param aEventMetaData The meta data to by supplied by the event.
	 * @param aSource The source from which this event originated.
	 */
	public MetaDataEventImpl( EventMetaData aEventMetaData, SRC aSource ) {
		super( aSource );
		_eventMetaData = aEventMetaData;
	}

	/**
	 * Constructs an event with the given meta Data.
	 * 
	 * @param channel The value for {@link EventMetaData#getChannel()}
	 *        attribute.
	 * @param aSource The source from which this event originated.
	 */
	public MetaDataEventImpl( String channel, SRC aSource ) {
		super( aSource );
		_eventMetaData = new EventMetaDataImpl( channel, RuntimeUtility.getCallerStackTraceElement( MetaDataEventImpl.class ) );
	}

	/**
	 * Constructs an event with the given meta Data.
	 * 
	 * @param  The type of the action stored in the event. CAUTION: The
	 *        drawback of not using generic generic type declaration on a class
	 *        level is no granted type safety, the advantage is the ease of use:
	 *        Sub-classes can be used out of the box.
	 * 
	 * @param aEventMetaData The meta data to by supplied by the event.
	 * 
	 * @param aAction The action which the {@link ActionEvent} represents.
	 * 
	 * @param aSource The source from which this event originated.
	 */
	public MetaDataEventImpl( SRC aSource ) {
		super( aSource );
		_eventMetaData = new EventMetaDataImpl( RuntimeUtility.getCallerStackTraceElement( MetaDataEventImpl.class ) );
	}

	// /////////////////////////////////////////////////////////////////////////
	// METHODS:
	// /////////////////////////////////////////////////////////////////////////

	@Override
	public EventMetaData getMetaData() {
		return _eventMetaData;
	}
}