IBM MQ provides two Java language interfaces: IBM MQ classes for Java Message Service and IBM MQ classes for Java.
Within IBM MQ there are two alternative APIs for use
in Java applications:
IBM MQ classes for JMS
IBM MQ classes for Java Message Service (JMS) is the JMS provider that is supplied with IBM MQ. The Java Platform, Enterprise Edition
Connector Architecture (JCA) provides a standard way of connecting applications
running in a Java EE environment to an Enterprise
Information System (EIS) such as IBM MQ or Db2®.
IBM MQ classes for Java
IBM MQ classes for Java enable you to use IBM MQ in a Java
environment. IBM MQ classes for Java allow a Java application to connect to IBM MQ as an IBM MQ client, or connect directly to an IBM MQ queue
manager.Note: IBM MQ classes for Java are
functionally stabilized at the level shipped in IBM MQ Version 8.0. for more information, see Stabilization of IBM MQ classes for Java.