01: /*
02: * JBoss, Home of Professional Open Source.
03: * Copyright 2006, Red Hat Middleware LLC, and individual contributors
04: * as indicated by the @author tags. See the copyright.txt file in the
05: * distribution for a full listing of individual contributors.
06: *
07: * This is free software; you can redistribute it and/or modify it
08: * under the terms of the GNU Lesser General Public License as
09: * published by the Free Software Foundation; either version 2.1 of
10: * the License, or (at your option) any later version.
11: *
12: * This software is distributed in the hope that it will be useful,
13: * but WITHOUT ANY WARRANTY; without even the implied warranty of
14: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15: * Lesser General Public License for more details.
16: *
17: * You should have received a copy of the GNU Lesser General Public
18: * License along with this software; if not, write to the Free
19: * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20: * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
21: */
22: package javax.jms;
23:
24: /** A <CODE>ServerSession</CODE> object is an application server object that
25: * is used by a server to associate a thread with a JMS session (optional).
26: *
27: * <P>A <CODE>ServerSession</CODE> implements two methods:
28: *
29: * <UL>
30: * <LI><CODE>getSession</CODE> - returns the <CODE>ServerSession</CODE>'s
31: * JMS session.
32: * <LI><CODE>start</CODE> - starts the execution of the
33: * <CODE>ServerSession</CODE>
34: * thread and results in the execution of the JMS session's
35: * <CODE>run</CODE> method.
36: * </UL>
37: *
38: * <P>A <CODE>ConnectionConsumer</CODE> implemented by a JMS provider uses a
39: * <CODE>ServerSession</CODE> to process one or more messages that have
40: * arrived. It does this by getting a <CODE>ServerSession</CODE> from the
41: * <CODE>ConnectionConsumer</CODE>'s <CODE>ServerSessionPool</CODE>; getting
42: * the <CODE>ServerSession</CODE>'s JMS session; loading it with the messages;
43: * and then starting the <CODE>ServerSession</CODE>.
44: *
45: * <P>In most cases the <CODE>ServerSession</CODE> will register some object
46: * it provides as the <CODE>ServerSession</CODE>'s thread run object. The
47: * <CODE>ServerSession</CODE>'s <CODE>start</CODE> method will call the
48: * thread's <CODE>start</CODE> method, which will start the new thread, and
49: * from it, call the <CODE>run</CODE> method of the
50: * <CODE>ServerSession</CODE>'s run object. This object will do some
51: * housekeeping and then call the <CODE>Session</CODE>'s <CODE>run</CODE>
52: * method. When <CODE>run</CODE> returns, the <CODE>ServerSession</CODE>'s run
53: * object can return the <CODE>ServerSession</CODE> to the
54: * <CODE>ServerSessionPool</CODE>, and the cycle starts again.
55: *
56: * <P>Note that the JMS API does not architect how the
57: * <CODE>ConnectionConsumer</CODE> loads the <CODE>Session</CODE> with
58: * messages. Since both the <CODE>ConnectionConsumer</CODE> and
59: * <CODE>Session</CODE> are implemented by the same JMS provider, they can
60: * accomplish the load using a private mechanism.
61: *
62: * @see javax.jms.ServerSessionPool
63: * @see javax.jms.ConnectionConsumer
64: */
65:
66: public interface ServerSession {
67:
68: /** Return the <CODE>ServerSession</CODE>'s <CODE>Session</CODE>. This must
69: * be a <CODE>Session</CODE> created by the same <CODE>Connection</CODE>
70: * that will be dispatching messages to it. The provider will assign one or
71: * more messages to the <CODE>Session</CODE>
72: * and then call <CODE>start</CODE> on the <CODE>ServerSession</CODE>.
73: *
74: * @return the server session's session
75: *
76: * @exception JMSException if the JMS provider fails to get the associated
77: * session for this <CODE>ServerSession</CODE> due
78: * to some internal error.
79: **/
80:
81: Session getSession() throws JMSException;
82:
83: /** Cause the <CODE>Session</CODE>'s <CODE>run</CODE> method to be called
84: * to process messages that were just assigned to it.
85: *
86: * @exception JMSException if the JMS provider fails to start the server
87: * session to process messages due to some internal
88: * error.
89: */
90:
91: void start() throws JMSException;
92: }
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