You can use the connection factory attributes listed in Table 18–8 to override the values set by a client for certain JMS message header fields. The settings you specify will be used for all messages produced by connections obtained from that connection factory. Header fields that you can override in this way are
Delivery mode (persistent or nonpersistent)
There are two attributes for each of these fields: one boolean, to control whether the field can be overridden, and another to specify its value. For instance, the attributes for setting the priority level are imqOverrideJMSPriority and imqJMSPriority. There is also an additional attribute, imqOverrideJMSHeadersToTemporaryDestinations, that controls whether override values apply to temporary destinations.
Because overriding message headers may interfere with the needs of specific applications, these attributes should only be used in consultation with an application’s designers or users.