Applying a message oriented middleware architecture to the TJ-II remote participation system

A message oriented middleware (MOM) has been introduced into the TJ-II data acquisition system to on-line distribute information. Java message service (JMS) has been chosen as the messaging application program interface (API) in order to ensure multiplatform portability. A library of C++ classes providing interface for JMS Java classes has been developed. This allows C++ programs to inter-communicate through JMS. In addition, a set of C wrapper functions has also been developed to provide basic messaging functionalities for C or FORTRAN programs. These functions are used in TJ-II LabView data acquisition applications. Several software applications that take advantage of the MOM architecture have been developed. Firstly, a general-user application allows monitoring of the data acquisition systems. Secondly, a simple application permits the visualization of TJ-II monitor signals with on-line data refreshing. These applications are written in the Java language, thereby ensuring its portability. These software tools provide new functionalities to the TJ-II remote participation system and are equally used in the local environment.