https://xml.apache.org/xalan-j/apidocs/org/apache/xpath/patterns/FunctionPattern.html
Xalan-Java 2.7.1: Class FunctionPattern
javaclass
https://access.redhat.com/webassets/avalon/d/red_hat_jboss_enterprise_application_platform/7.3/javadocs/org/apache/xpath/patterns/FunctionPattern.html
FunctionPattern (Red Hat JBoss Enterprise Application Platform 7.3.0.GA public API)
red hat jboss