// Copyright (c) 2004 Just Objects B.V. <just@justobjects.nl>// Distributable under LGPL license. See terms of license at gnu.org.package nl.justobjects.pushlet.core;/** * Constants for Pushlet protocols. * * @author Just van den Broecke - Just Objects &copy; * @version $Id: Protocol.java,v 1.15 2007/11/23 14:33:07 justb Exp $ */public interface Protocol {	/**	 * Default URI .	 */	public static final String DEFAULT_SERVLET_URI = "/pushlet/pushlet.srv";	//	// Common protocol header/parameter names	//	/**	 * Event type (join, leave, data, subscribe etc) .	 */	public static final String P_EVENT = "p_event";	/**	 * Time in seconds since 1970	 */	public static final String P_TIME = "p_time";	/**	 * Event sequence number, numbers per-client.	 */	public static final String P_SEQ = "p_seq";	/**	 * Subject (topic) of data event.	 */	public static final String P_SUBJECT = "p_subject";	/**	 * Originator of Event.	 */	public static final String P_FROM = "p_from";	/**	 * Addressee of Event, subject or client p_id.	 */	public static final String P_TO = "p_to";	/**	 * Identifier for client instance within server.	 */	public static final String P_ID = "p_id";	/**	 * Subscription id, identifies single subscription.	 */	public static final String P_SUBSCRIPTION_ID = "p_sid";	/**	 * Format to receive events	 */	public static final String P_FORMAT = "p_format";	/**	 * Protocol mode.	 */	public static final String P_MODE = "p_mode";	/**	 * Reason for errors.	 */	public static final String P_REASON = "p_reason";	/**	 * URL attribute.	 */	public static final String P_URL = "p_url";	/**	 * Wait attribute.	 */	public static final String P_WAIT = "p_wait";	/**	 * Subscription label, may be used to return user-specific	 * token with a data event, e.g. the name of a function for a callback.	 */	public static final String P_SUBSCRIPTION_LABEL = "p_label";	//	// Event values with direction for P_EVENT (C=client, S=server)	//	/**	 * C-->S Request to join server.	 */	public static final String E_JOIN = "join";	/**	 * S-->C Acknowledgement of join.	 */	public static final String E_JOIN_ACK = "join-ack";	/**	 * C-->S Request to join server.	 */	public static final String E_JOIN_LISTEN = "join-listen";	/**	 * S-->C Acknowledgement of join.	 */	public static final String E_JOIN_LISTEN_ACK = "join-listen-ack";	/**	 * C-->S Client starts listening.	 */	public static final String E_LISTEN = "listen";	/**	 * S-->C Ack of listen.	 */	public static final String E_LISTEN_ACK = "listen-ack";	/**	 * C-->S Client leaves server.	 */	public static final String E_LEAVE = "leave";	/**	 * S-->C Ack of leave.	 */	public static final String E_LEAVE_ACK = "leave-ack";	/**	 * C-->S Publish to subject.	 */	public static final String E_PUBLISH = "publish";	/**	 * S-->C Publish to subject acknowledge.	 */	public static final String E_PUBLISH_ACK = "publish-ack";	/**	 * C-->S Subscribe to subject request.	 */	public static final String E_SUBSCRIBE = "subscribe";	/**	 * S-->C Subscribe to subject acknowledge.	 */	public static final String E_SUBSCRIBE_ACK = "subscribe-ack";	/**	 * C-->S Unsubscribe from subject request.	 */	public static final String E_UNSUBSCRIBE = "unsubscribe";	/**	 * S--C Unsubscribe from subject acknowledge.	 */	public static final String E_UNSUBSCRIBE_ACK = "unsubscribe-ack";	/**	 * S-->C Client error response, transitional error.	 */	public static final String E_NACK = "nack";	/**	 * S-->C Client should abort, permanent error.	 */	public static final String E_ABORT = "abort";	/**	 * S-->C Data.	 */	public static final String E_DATA = "data";	/**	 * S-->C or C-->S Heartbeat.	 */	public static final String E_HEARTBEAT = "hb";	/**	 * S-->C S-->C or C-->S Heartbeat confirmed.	 */	public static final String E_HEARTBEAT_ACK = "hb-ack";	/**	 * S-->C or C-->S client refresh of data channel.	 */	public static final String E_REFRESH = "refresh";	/**	 * S-->C client should refresh data channel.	 */	public static final String E_REFRESH_ACK = "refresh-ack";	//	// Values for P_FORMAT parameter	//	/**	 * JavaScript callback.	 */	public static String FORMAT_JAVASCRIPT = "js";	/**	 * Java serialized object.	 */	public static String FORMAT_SERIALIZED_JAVA_OBJECT = "ser";	/**	 * Stream of XML documents.	 */	public static String FORMAT_XML = "xml";	/**	 * Single XML document containing zero or more events.	 */	public static String FORMAT_XML_STRICT = "xml-strict";	//	// Values for P_MODE parameter	//	public static final String MODE_STREAM = "stream";	public static final String MODE_PULL = "pull";	public static final String MODE_POLL = "poll";	//	// Values for special/reserved subjects	// TODO: use these to publish events when clients do these actions	// TODO: Dispatcher may intercept these subjects to send cached events	//	public static final String SUBJECT_META = "/meta";	public static final String SUBJECT_META_SUBS = SUBJECT_META + "/subs";	public static final String SUBJECT_META_JOINS = SUBJECT_META + "/joins";}/*  * $Log: Protocol.java,v $  * Revision 1.15  2007/11/23 14:33:07  justb  * core classes now configurable through factory  *  * Revision 1.14  2006/10/19 12:33:40  justb  * add atomic join-listen support (one request)  *  * Revision 1.13  2005/05/06 19:44:00  justb  * added xml-strict format  *  * Revision 1.12  2005/02/28 13:05:59  justb  * introduced join-listen protocol service  *  * Revision 1.11  2005/02/28 12:45:59  justb  * introduced Command class  *  * Revision 1.10  2005/02/16 12:16:17  justb  * added support for "poll" mode  *  * Revision 1.9  2005/01/24 22:46:02  justb  * getting safari to work  *  * Revision 1.8  2005/01/24 13:42:00  justb  * new protocol changes (p_listen)  *  * Revision 1.7  2005/01/18 16:47:10  justb  * protocol changes for v2 and publishing from pushlet client  *  * Revision 1.6  2005/01/13 14:47:15  justb  * control evt: send response on same (control) connection  *  * Revision 1.5  2004/10/24 13:52:52  justb  * small fixes in client lib  *  * Revision 1.4  2004/10/24 12:58:18  justb  * revised client and test classes for new protocol  *  * Revision 1.3  2004/09/20 22:01:38  justb  * more changes for new protocol  *  * Revision 1.2  2004/09/03 22:35:37  justb  * Almost complete rewrite, just checking in now  *  * Revision 1.1  2004/09/03 21:02:20  justb  * make more formalized protocol  *  *  */