package envoy.event;

import java.io.Serializable;

/**
 * Project: <strong>envoy-common</strong><br>
 * File: <strong>Event.java</strong><br>
 * Created: <strong>04.12.2019</strong><br>
 *
 * @author Kai S. K. Engelbart
 * @param <T> the type of the Event
 * @since Envoy v0.2-alpha
 */
public abstract class Event<T> implements Serializable {

	protected final T value;

	private static final long serialVersionUID = 4673659457380399167L;

	protected Event(T value) { this.value = value; }

	/**
	 * @return the data associated with this event
	 */
	public T get() { return value; }

	@Override
	public String toString() { return String.format("%s[value=%s]", this.getClass().getSimpleName(), value); }

	/**
	 * Serves as a super class for events that do not carry a value.<br>
	 * <br>
	 * Project: <strong>envoy-common</strong><br>
	 * File: <strong>Event.java</strong><br>
	 * Created: <strong>11 Feb 2020</strong><br>
	 *
	 * @author Kai S. K. Engelbart
	 * @since Envoy Common v0.2-alpha
	 */
	public static abstract class Valueless extends Event<Void> {

		private static final long serialVersionUID = -9019362144094097997L;

		protected Valueless() { super(null); }

		@Override
		public String toString() { return this.getClass().getSimpleName(); }
	}
}