In the following URL[1] and 4.5.2. Migrate JBoss Web Rewrite Conditions section, it is linked to "Undertow Predicates Attributes and Handlers". But this refers to "http://undertow.io/undertow-docs/undertow-docs-1.2.0/index.html#predicates-attributes-and-handlers". Undertow version is 2.x in EAP 7.2. It is out of date.
[2] is new one.

[1]
https://access.redhat.com/documentation/en-us/red_hat_jboss_enterprise_application_platform/7.2.beta/html-single/migration_guide/#migrate_jboss_web_rewrite_conditions

[2] http://undertow.io/undertow-docs/undertow-docs-2.0.0/#programmatic-representation-of-predicates