This is the command used to invoke your Java runtime system which runs the devtools wrapper classes -- for example, on the Oracle's reference implementation the following commands are used:
/bin/java
/jre/java
Either type the path in the text box, or click Browse to invoke a file chooser to make your selection.
Devtools is used in this section to refer to the schema compiler, the schema generator, the Java-to-WSDL mappings and the WSDL-to-Java mappings. See the JCK User's Guide for detailed information about the devtools wrapper classes.