The MicroProfile Config specification provides a unified mechanism to access configuration, providing a single view of multiple sources.
To enable the MicroProfile Config 1.2 feature, add the following element declaration inside the featureManager element in your server.xml file:
<feature>mpConfig-1.2</feature>
If you are developing a feature that depends on the MicroProfile Config 1.2 feature, include the following item in the Subsystem-Content header in the feature manifest file for your new feature:
com.ibm.websphere.appserver.mpConfig-1.2; type="osgi.subsystem.feature"