question: public X509Certificate generateX509Certificate ( PrivateKey key ) throws SecurityException , SignatureException , InvalidKeyException { try { return generateX509Certificate ( key , "BC" , null ) ; } catch ( NoSuchProviderException e ) { throw new SecurityException ( "BC provider not installed!" ) ; } }
target:  generate an X509 certificate, based on the current issuer and subject using the default provider "BC".