A Destination object encapsulates a provider-specific
address.
The JMS API does not define a standard address syntax. Although a standard
address syntax was considered, it was decided that the differences in
address semantics between existing message-oriented middleware (MOM)
products were too wide to bridge with a single syntax.
Since Destination is an administered object, it may
contain
provider-specific configuration information in addition to its address.
The JMS API also supports a client's use of provider-specific address
names.
Destination objects support concurrent use.
A Destination object is a JMS administered object.
JMS administered objects are objects containing configuration
information that are created by an administrator and later used by
JMS clients. They make it practical to administer the JMS API in the
enterprise.
Although the interfaces for administered objects do not explicitly
depend on the Java Naming and Directory Interface (JNDI) API, the JMS API
establishes the convention that JMS clients find administered objects by
looking them up in a JNDI namespace.
An administrator can place an administered object anywhere in a
namespace. The JMS API does not define a naming policy.
It is expected that JMS providers will provide the tools an
administrator needs to create and configure administered objects in a
JNDI namespace. JMS provider implementations of administered objects
should implement the javax.naming.Referenceable and
java.io.Serializable interfaces so that they can be stored in
all JNDI naming contexts. In addition, it is recommended that these
implementations follow the JavaBeansTM
design patterns.
This strategy provides several benefits:
- It hides provider-specific details from JMS clients.
- It abstracts JMS administrative information into objects in the Java
programming language ("Java objects")
that are easily organized and administered from a common
management console.
- Since there will be JNDI providers for all popular naming
services, JMS providers can deliver one implementation
of administered objects that will run everywhere.
An administered object should not hold on to any remote resources.
Its lookup should not use remote resources other than those used by the
JNDI API itself.
Clients should think of administered objects as local Java objects.
Looking them up should not have any hidden side effects or use surprising
amounts of local resources. | 