public void testGetCertificateIssuer(){
  assertNull("The default implementation should return null.",tbt_crlentry.getCertificateIssuer());
}

public void testGetCertificateIssuer ( ) { assertNull ( "The default implementation should return null." , tbt_crlentry . getCertificateIssuer ( ) ) ; }
getcertificateissuer ( ) method testing . tests if the method throws appropriate exception .
