If by "has enough code to run crypto inside of it", you mean "the SSL support and the javax.crypto library", sure, it gives you some useful stuff. You can also

If by "has enough code to run crypto inside of it", you mean "the SSL support and the javax.crypto library", sure, it gives you some useful stuff. You can also access all that stuff from JS without ever writing a line of Java code, so that's a wash. As far as self-contained Java applets go, every attack that can be used against JS can be used against Java. It's a trivial exercise to instrument any method call you like, including calls to any method that attempts any kind of verification. Java bytecode is really quite transparent.