act like additional headers that can be assigned to a message. They
provide the developer with more information about the message. The
interface provides several accessor
and mutator methods for reading and writing properties. The value of
a property can be a
There are three basic categories of message properties:
JMS-defined properties, and provider-specific properties.
Application properties are defined and applied to
Message objects by the application developer; the
JMS extension and provider-specific properties are additional headers
that are, for the most part, automatically added by the JMS provider.
Any property defined by the application developer can be an application-specific property. Application properties are set before the message is delivered. There are no predefined application properties; developers are free to define any properties that fit their needs. For example, in the chat example developed in Chapter 2, a special property could be added that identifies the user sending the message:
TextMessage message = pubSession.createTextMessage( ); message.setText(text);
As an application specific-property,
not meaningful outside the
Chat application; it is used exclusively by the application to filter messages based on the identity of the ...