The documentation bug occurs in the following section of the Deploying AMQ Broker on OpenShift : https://access.redhat.com/documentation/en-us/red_hat_amq/7.7/html/deploying_amq_broker_on_openshift/reference-broker-ocp-broker-ocp#ref_br-custom-resource-definition-config-reference_broker-ocp

Specify whether to use asynchronous I/O (AIO) or non-blocking I/O (NIO).

*Type*: string

*Example*: nio

*Default value*: aio

The default value, if journal-type is omitted from the configuration is NIO.