JavaTM Platform, Enterprise Edition, v 5.0
javax.jms
Interface DeliveryMode
public interface DeliveryMode
The delivery modes supported by the JMS API are PERSISTENT and
NON_PERSISTENT .
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.
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 PERSISTENT
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.
A message is guaranteed to be delivered once and only once
by a JMS provider if the delivery mode of the message is
PERSISTENT
and if the destination has a sufficient message retention policy.
- Version:
- 1.0 - 7 August 1998
- Author:
- Mark Hapner, Rich Burridge
Field Summary |
static int |
NON_PERSISTENT
This is the lowest-overhead delivery mode because it does not require
that the message be logged to stable storage. |
static int |
PERSISTENT
This delivery mode instructs the JMS provider to log the message to stable
storage as part of the client's send operation. |
NON_PERSISTENT
static final int NON_PERSISTENT
- 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
NON_PERSISTENT message to be lost is
not defined.
A JMS provider must deliver a NON_PERSISTENT message
with an
at-most-once guarantee. This means that it may lose the message, but it
must not deliver it twice.
- See Also:
- Constant Field Values
PERSISTENT
static final int PERSISTENT
- 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
PERSISTENT message to be lost.
- See Also:
- Constant Field Values
Copyright 2003 Sun Microsystems, Inc. All rights reserved
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