public MultiErrorException check(String fieldName,boolean valid,String messageKey,Object... args){
  if (!valid)   errors.add(new FieldError(fieldName,messageKey,LemonUtil.getMessage(messageKey,args)));
  return this;
}

public MultiErrorException check ( String fieldName , boolean valid , String messageKey , Object ... args ) { if ( ! valid ) errors . add ( new FieldError ( fieldName , messageKey , LemonUtil . getMessage ( messageKey , args ) ) ) ; return this ; }
adds a field - error if the given condition isn ' t true
