Dave, I think you are thinking about this the same way we are. Bob Lee and I agreed when we met up during JavaOne that there should be just one stack to handle 90% of the needs of users. The actual logical differences in the stack (form submit vs. "view") should be handled by conventions and/or configuration (either XML or annotations). Your marker interface, Submittable, represents that same line of thought.
I'll ask Bob to comment on what his thoughts are around this. Patrick > Hello all, > > On this page: > http://wiki.apache.org/struts/StrutsActionRelease200 > > There is, under the new features heading a reference > to the > validation/workflow issues brought up on this page: > http://wiki.apache.org/struts/RoughSpots?action=show > > Under the main list, item number 16, and under > Patrick's list, item > number 4 and 5, there is discussion of the default > workflow and its > relation to the idea of view vs. update requests to > the same action. > > I haven't seen any discussion of this on the dev > list, and i'm wondering > if anyone is actively working on this and what > directions are being > considered. In trying to work this out for myself, i > came up with a > simple solution for the main use case, and i would > like to share it here > and ask for comments. > > The main idea is that the Prepareable interceptor is > used to setup the > view, and another interceptor called > SubmittableInterceptor is added to > the end of the default interceptor stack and is used > to determine if a > form submission has occured. A marker interface > called Submittable > allows the user, via a boolean wasSubmitted method, > to determine how the > action will determine if a form submission has > occured, whether it be > the POST vs GET idea, the inclusion of a hidden flag > field, or the > presence of a submit or button parameter. It also has > a "submit" method > that can be used optionally to process the submission > and return a > result string. > > The SubmittableInterceptor will see if wasSubmitted > returns true, and if > so, run the submit method. If the submit method > returns a result string, > the interceptor returns that, otherwise the > interceptor stack invocation > continues. If the form was not submitted, the > interceptor returns the > INPUT result, displaying the form, which has been > setup by Prepareable. > > My BaseAction extends ActionSupport and implements > Submittable and > allows for the inclusion of the > SubmittableInterceptor into the default > stack, with default behavior that does nothing. > > The Validate method of the action will also check > wasSubmitted to > determine if it should validate, this could be > eliminated by either > putting SubmittableInterceptor before the > DefaultWorkflowInterceptor or > by putting the SubmittableInterceptor logic in > DefaultWorkflowInterceptor. > > The code: > > [code] > public interface Submittable { > > boolean wasSubmitted(); > String submit(); > } > [/code] > > SubmittableInterceptor intercept method: > > [code] > public String intercept(ActionInvocation invocation) > throws Exception { > Object action = invocation.getAction(); > if (action instanceof Submittable) { > Submittable submittable = (Submittable) action; > if (submittable.wasSubmitted()) { > String submitResult = submittable.submit(); > if (submitReturn != null && ! > submitReturn.equals("")) { > return submitResult; > } > else { > return Action.INPUT; > } > return invocation.invoke(); > > > public class BaseAction extends ActionSupport > implements Submittable { > > public boolean wasSubmitted() { > return true; > } > > public String submit() { > return null; > } > } > > public class TesterAction extends BaseAction > implements Preparable, > ServletRequestAware { > > private HttpServletRequest request; > public void setServletRequest(HttpServletRequest r) > { > this.request = r; > > > private String act = ""; > private String name = ""; > > public String getAct() { > return this.act; > } > public void setAct(String s) { > this.act = s; > } > > public String getName() { > return this.name; > } > public void setName(String s) { > this.name = s; > } > > public void validate() { > if (wasSubmitted()) { > if (name.equals("")) { > addFieldError("name", "required"); > } > } > } > > public void prepare() { > // setup view > request.setAttribute("form_name", "Test Form"); > } > > public boolean wasSubmitted() { > if (act.equals("")) { > return false; > } > else { > return true; > } > } > > public String submit() { > // allow execute to do business logic > return null; > } > > public String execute() throws Exception { > // do business logic > return SUCCESS; > } > } > [/code] > > > > ------------------------------------------------------ > --------------- > To unsubscribe, e-mail: > [EMAIL PROTECTED] > For additional commands, e-mail: > [EMAIL PROTECTED] --------------------------------------------------------------------- Posted via Jive Forums http://forums.opensymphony.com/thread.jspa?threadID=33417&messageID=65333#65333 --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
