Co-ordination of multiple external representations during Java program debugging

Java program debugging was investigated in computer science students who used a software debugging environment (SDE) that provided concurrently displayed, adjacent, multiple and linked representations consisting of the program code, a visualisation of the program, and its output. The aim of this investigation was to address questions such as 'To what extent do programmers use each type of representation?', 'Are particular patterns of representation use associated with superior debugging performance?', 'Are graphical representations more helpful to Java programmers than textual ones?' and 'Are representations that highlight data structure more useful than those that highlight control-flow for Java debugging?