eventdispatcher.java

SMPP（点到点短消息协议）的java实现

package ie.omk.smpp.event;

import ie.omk.smpp.Connection;
import ie.omk.smpp.message.SMPPPacket;

import java.util.Iterator;

/**
 * This interface defines the observable side of the observer pattern for
 * asynchronous SMPP event notification. Each {@link ie.omk.smpp.Connection}
 * object will have an implementation of the <code>EventDispatcher</code>
 * interface which it uses to deliver events to interested listeners. By
 * removing the actual dispatching of events from the internals of the
 * Connection, applications may provide their own event dispatch implementations
 * for their <code>Connection</code> objects which better suit how those
 * applications work.
 * 
 * @author Oran Kelly
 * @version $Id: EventDispatcher.java 255 2006-03-09 09:34:37Z orank $
 * @see ie.omk.smpp.event.SimpleEventDispatcher
 */
public interface EventDispatcher {

    /**
     * Initialise the event dispatcher. The <code>init</code> method will be
     * called by the <code>Connection</code> before it makes any attempt to
     * add any observers or deliver any events via the dispatcher.
     */
    void init();

    /**
     * Event dispatcher clean up. The <code>destroy</code> method will be
     * called by the <code>Connection</code> when it is finished delivering
     * events to it and the receiver daemon thread is exiting. Any initialising
     * done in the <code>init</code> method can be cleaned up here.
     * <p>
     * The <code>destroy</code> method <b>must not </b> interfere with the
     * delivery of any events notified to the event dispatcher before the call
     * to this method.
     * </p>
     */
    void destroy();

    /**
     * Add an observer to this event dispatcher.
     * 
     * @param observer
     *            the observer object to add.
     */
    void addObserver(ConnectionObserver observer);

    /**
     * Remove an observer from this event dispatcher.
     * 
     * @param observer
     *            the observer object to remove from the registered observers.
     */
    void removeObserver(ConnectionObserver observer);

    /**
     * Get an iterator over the currently registered observers.
     * 
     * @return an iterator object which iterates over all registered observers.
     */
    Iterator observerIterator();

    /**
     * Notify all registered observers of an SMPP event.
     * 
     * @param event
     *            the SMPP event to notify observers of.
     */
    void notifyObservers(Connection conn, SMPPEvent event);

    /**
     * Notify all registered observers of a received SMPP packet.
     * 
     * @param packet
     *            the SMPP packet to notify observers of.
     */
    void notifyObservers(Connection conn, SMPPPacket packet);
}