the eclipse doc says that "Making an API field final breaks compatibility with pre-existing binaries that attempt to assign new values to the field.".
assuming nobody tried to do this, I think making the fields final should be OK. on a related topic, any reason why these bunnies in JWSHandler are not static: public final String OPTION_JWS_FILE_EXTENSION = "extension"; public final String DEFAULT_JWS_FILE_EXTENSION = ".jws"; We cannot change these; it apparently results in a link time error. Bugger. I wanted to refer to it in the servlets where we check for whether a JWS file exists. I am about to add the JWS extension to the Constants class as a static, and defining the JWSHandler version of it from the constants.