<< Previous << [Session1 Index] >> Next >>
Question: Which Data object method grants an authority and needs to be encapsulated as a separate capability?
Of course, Java makes no distinction between the functions that require capabilities and those which do not, except in the most gross fashion: in Java, there is no function for setting the current date! One of the first and simplest programs developed for windowed operating systems, the Clock program, cannot be written in Java! Just as Java's capabilities associated with ReadStreams in an earlier example were too powerful for security, Java's capabilities associated with Dates are too weak for general-purpose programming. We can, and must, do better. Fortunately, we can.