We had a customer issue a few weeks back ... 'really Tim, I never would have guessed' :0) Yeah, we get some issues sometimes. This was a JD Edwards customer that had developed an encoding class for a barcode. Lost? Check out the Advanced Barcode Support article. Basically, some barcodes need the data encoded, calculating stop bits and such like, prior to applying the barcode font. To support this, we allow you to create a java class that implements a Publisher interface to encode the data values. This can then be called from the RTF template layer using commands - check the user guide people!
The encoding class needs to be in the classpath on the server be it JDE, EBS or standalone - this is straightforward enough but how about being able to test on the Template Builder for Word interface?
It can be done, no support directly in the tool but with a little jiggery pokery we can get the class tested. The list of jar files that the builder will load at runtime is limited but the main one we can highjack is the xdocore.jar. You'll find it under the jlib directory under the Template Builder install directory.

You can open the jar file using something like WinZip, with it you can see the structure of the contents,

The class you developed will no doubt have a package declaration in it e.g. oracle.apps.xx.xmlp.barcode - this needs to map to the path in the jar file. To get it into the jar in the right place just get the class into the directory path on your local drive.

Then, in the case of Winzip, open the jar, then drag and drop the class and ensure the 'Use Full Path Info' option is set to get the class into the correct path that will map to your package specification.

Now, you can test to your hearts content in the comfort and relative speed of MSWord.