To create jeus-connector-dd.xml, you need to consider the following:
Whether or not <outbound-resourceadapter><connection-definition> setting exists in the ra.xml file
An outbound settings may not exist since the resource adapter may be used only for inbound communications. If outbound settings are not required, a user does not need to create the jeus-connector-dd.xml file. However, if the <connection-definition> setting exists, the jeus-connector-dd.xml file is required to create a connection pool according to the setting.
Whether or not two or more <outbound-resourceadapter><connection-definition> settings exist in the ra.xml file
If there are two or more <connection-definition> settings, a connection pool should be created for each. Note that the <connection-definition> value should be used to set the <connectionfactory-interface> value in the jeus-connector-dd.xml file. Refer to "2.3. Example of Connection Pool Configuration".
If you do not want to create a connection pool, change the setting in the ra.xml file.
To adjust settings of a Work Manager
Even though the jeus-connector-dd.xml file has not been configured, by default, a Work Manager is provided for the resource adapter. JEUS does not automatically initialize the Work Manager because it is created only when the resource adapter needs the Manager.
JEUS creates a Work Manager upon request. The Work Manager configuration can be considered as that of the thread pool. To adjust the number of threads, create the jeus-connector-dd.xml file and configure the Work Manager setting. For more information, refer to "3.1.2. Work Manager Configuration".