As for AP CS and Java at Universities: java is here to stay for the immediate future.Also, I am not completely dull on the topic of Java, I have taken the time to learn the language, so that I may present a valid arguement. I have to say, from what I saw in the course that I was in from the other students, when people go from Java to C++, it's a pretty good jolt. Seeing as, because of the AP board switch, my school completely stopped teaching C++ that year, I started offering to teach kids C++ after school, and I noticed that the people who had learned Java initially had the most trouble understanding memory management and such, seeing as they've been working in an environment where you don't have to clean up after yourselves at all.
AS for Your school if there was enough enrollment it could offer courses on other languages. Many high school teachers I spoke with at Clemson- teach other languages like C++ and Scheme to their students.
As for the Java vs. C++, both have merits and problems.