The java.security.Certificate class is deprecated. Some internal security classes have dependencies on this class (and more specifically the subclass sun.security.x509.X509Cert) which can probably be removed. Eliminating this dependency helps reduce the number and size of the security classes in the base module.

See suggested fix for sun.security.x509.CertAndKeyGen.

There is another dependency in sun.tools.jar.JarVerifierStream. I am not sure it is safe to remove some of that code.