I believe at the beginning of the job you need to use the tLibraryLoad component, then you can use the library in the tJava, tJavaRow, and maybe the tJavaFlex components. However, be warned: the loaded library will not be available in any other component where custom code can be added like in the tMap... As far as I am concerned it is a bug, Talend does not seem to agree.
Thanks Gábor. I have a large set of jar files which are to be included in the build path. Creating a tLibraryLoad component for each one of them doesn't seem feasible. Is there any alternate way to add the whole lib folder to the build path or select several jars at a single time in the library load component? Thanks, Jonny