public void addInterface(SootClass interfaceClass){
  checkLevel(HIERARCHY);
  if (implementsInterface(interfaceClass.getName()))   throw new RuntimeException("duplicate interface: " + interfaceClass.getName());
  interfaces.add(interfaceClass);
}

public void addInterface ( SootClass interfaceClass ) { checkLevel ( HIERARCHY ) ; if ( implementsInterface ( interfaceClass . getName ( ) ) ) throw new RuntimeException ( "duplicate interface: " + interfaceClass . getName ( ) ) ; interfaces . add ( interfaceClass ) ; }
add the given class to the list of interfaces which are directly implemented by this class .
