The Java interface of MDSplus: towards a unified approach for local and remote data access

The paper presents the main design concepts of the new Java interface of the MDSplus system, a data acquisition system currently in use in several fusion devices that is becoming the standard ‘de facto’ for data access in US fusion laboratories. The interface is currently composed of two tools, which represent the extension of the two original, X-Windows-based MDSplus interface tools. The first one, called jScope, provides interactive display of stored waveforms. The second one, called jTraverser, provides graphical support for navigation into the tree structure of the pulse files and for the set-up of experiment devices. Though both tools support network communication, remote data access has been considered as a key issue for jScope, in order to make it a general purpose tool for data display, which can be connected to a variety of experiments. Our experience in the development of these tools confirmed the widespread concept about the promising features of the Java language. In particular, the object oriented organization of the language and the rich set of support classes allowed an impressive reduction in the time required for development and testing.