Thanks for the reply. Using this strategy, how would you display any incorrect input to the user if the getDisplay() method is getting the current value of the data transfer object and the setDisplay(String s) method is filtering bad input? This is the issue I'm trying to solve. The only solution I could think of is having a String input variable to hold the input value. I hope I'm missing something. Thanks, Petra Ted Husted <[EMAIL PROTECTED]> wrote: For more about ActionForms, see
http://www.mail-archive.com/[email protected]/msg19281.html http://www.mail-archive.com/[email protected]/msg19338.html http://www.mail-archive.com/[email protected]/msg20833.html To move data between an ActionForm and another data transfer object, there are several strategies. The one I tend to use most is to place a helper "display" method on the business bean. On the ActionForm, there would be a standard property like getTimestampDisplay(). On the business bean, there is a matching set of properties that also use strings. But the business bean properties are not using a String field, but peforming the conversation. Something like this: public String getTicklerDisplay() { Timestamp tickler = getTickler(); if (ConvertUtils.isNull(tickler)) return null; return tickler.toString(); } public void setTicklerDisplay(String ticklerDisplay) { if (ticklerDisplay==null) setTickler(null); else try { setTickler(Timestamp.valueOf(ticklerDisplay)); } catch (Throwable t) { setTickler(null); } } So the business bean has a set of properties for the binary Timestamp field, and a second set that converts it back and forth to a String. This same strategy can be used for any property that needs to be converted, transformed, localized, or otherwise formatted. These issues really belong to the business layer anyway. It's the presentation layer's job to wrap data in HTML markup, but whether a name should be in uppercase, or last name first, or a date displayed in long format or short format, are all business requirements. -- Ted Husted, Husted dot Com, Fairport NY US -- Developing Java Web Applications with Struts -- Tel: +1 585 737-3463 -- Web: http://husted.com/about/services Peter Onthrops wrote: > > I have a form that has one attribute - an instance of a value object. The object has >multiple attributes that make up the form elements. These attributes are not all >Strings and therefore ConvertUtils converts them to Strings for display on the jsp. >When posting the html form, ConvertUtils attempts to convert the input Strings back >to the proper object Types. If the input string is not in the .toString() format of >the object, then an conversion exception is thrown. > > Does this mean that I would need to have all input attributes of type String? That >is, unless I modify ConvertUtils to accept multiple string formats for my objects. >What is the standard practice for creating form attributes that are not Strings (i.e. >Timestamp), populating them, and validating them. Correct me if I'm wrong, but it >seems that the validator assumes a String attribute for validation. > > Thanks in advance, > > P. > > --------------------------------- > Do You Yahoo!? > Sign-up for Video Highlights of 2002 FIFA World Cup -- To unsubscribe, e-mail: For additional commands, e-mail: --------------------------------- Do You Yahoo!? Sign-up for Video Highlights of 2002 FIFA World Cup
