private ErrorException getException(Environment env, InvalidMethod el, Messages.Item message, boolean prototype) {
            ErrorException e;
            if (prototype) {
                e = new FatalException(
                        message.fetch(
                                el.method.getPrototype().getSignatureString(false),
                                el.method.getSignatureString(false)
                        ),
                        el.method.getTrace()
                );
            } else {
                e = new FatalException(
                        message.fetch(el.method.getSignatureString(false)),
                        el.method.getTrace()
                );
            }
            return e;
        }
return empty list if success else list with not valid implemented methods in class

@param _interface
@return
jphp-runtime/src/php/runtime/reflection/ClassEntity.java