/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the License). You may not use this file except in
* compliance with the License.
*
* You can obtain a copy of the license at
* https://glassfish.dev.java.net/public/CDDLv1.0.html or
* glassfish/bootstrap/legal/CDDLv1.0.txt.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* Header Notice in each file and include the License file
* at glassfish/bootstrap/legal/CDDLv1.0.txt.
* If applicable, add the following below the CDDL Header,
* with the fields enclosed by brackets [] replaced by
* you own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
*/
package javax.jms;
/**
* The delivery modes supported by the JMS API are <CODE>PERSISTENT</CODE> and
* <CODE>NON_PERSISTENT</CODE>.
*
* <P>
* A client marks a message as persistent if it feels that the application will
* have problems if the message is lost in transit. A client marks a message as
* non-persistent if an occasional lost message is tolerable. Clients use
* delivery mode to tell a JMS provider how to balance message transport
* reliability with throughput.
*
* <P>
* Delivery mode covers only the transport of the message to its destination.
* Retention of a message at the destination until its receipt is acknowledged
* is not guaranteed by a <CODE>PERSISTENT</CODE> delivery mode. Clients
* should assume that message retention policies are set administratively.
* Message retention policy governs the reliability of message delivery from
* destination to message consumer. For example, if a client's message storage
* space is exhausted, some messages may be dropped in accordance with a
* site-specific message retention policy.
*
* <P>
* A message is guaranteed to be delivered once and only once by a JMS provider
* if the delivery mode of the message is <CODE>PERSISTENT</CODE> and if the
* destination has a sufficient message retention policy.
*
*
*
* @version 1.0 - 7 August 1998
* @author Mark Hapner
* @author Rich Burridge
*/
public interface DeliveryMode {
/**
* This is the lowest-overhead delivery mode because it does not require
* that the message be logged to stable storage. The level of JMS provider
* failure that causes a <CODE>NON_PERSISTENT</CODE> message to be lost is
* not defined.
*
* <P>
* A JMS provider must deliver a <CODE>NON_PERSISTENT</CODE> message with
* an at-most-once guarantee. This means that it may lose the message, but
* it must not deliver it twice.
*/
static final int NON_PERSISTENT = 1;
/**
* This delivery mode instructs the JMS provider to log the message to
* stable storage as part of the client's send operation. Only a hard media
* failure should cause a <CODE>PERSISTENT</CODE> message to be lost.
*/
static final int PERSISTENT = 2;
}
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