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
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
and if the destination has a sufficient message retention policy.
|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 |
A JMS provider must deliver a
|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 |