wizard form with spring mvc

2 0 1 1 - 1 0 - 3 0

Wizard form with Spring MVC

A B O U T M E

M ICHAŁ HUNIEWICZ

Michał Huniewicz is

a software engineer,

currently living in

England.

VIEW MY COM PLETE PROFILE

F O L L O W E R S

with Google Friend Connect

Members (80) More »

Already a member? Sign in

A F E W L I N K S . . .

My GitHub

My Homepage

My photos

Tamara BeJot [PL]

L A B E L S

Programming JavaPhotography Maven JBoss

Scala JPA Spring Hibernate CDI

HSQLDB JSF REST Gradle Guice

0 More Next Blog» Create Blog Sign In

B L O G . M 1 K E Y . M EJ A V A , J E E , S P R I N G , P H O T O G R A P H Y B L O G .

blog.m1key.me: Wizard form with Spring MVC http://blog.m1key.me/2011/10/wizard-form-with-spring-mvc.html

1 of 7 6/30/2013 1:57 PM

Today I will show you how to create a wizard form with Spring MVC.

A wizard form is a multi-step form that allows users to submit

information gradually. With Spring MVC it's very easy to make such

a form, as well as validate already submitted data on each step and

on finish.

Controller

This is the main thing. Let's take a detailed look.

The controller is annotated with the @Controller annotation.

@RequestMapping specifies its path. Also, we are storing user

submitted data (an instance of my custom transfer object called

PersonTo) in session with the @SessionAttributes annotation.

@Controller

@RequestMapping("/personRegistration")

@SessionAttributes("personTo")

public class PersonRegistrationController {

Now, let's take a look at initialisation code. The controller expects an

appropriate validator to be passed during construction time. The

validator is, in our case, a Spring bean, so we can have it autowired.

Then we initialise an init binder for the custom Gender enum. That

allows incoming string parameters to be converted into enum

instances.

@Autowired

public PersonRegistrationController(PersonRegistrationValidator valida

super();

this.validator = validator;

}

@InitBinder

public void initBinder(WebDataBinder binder) {

binder.registerCustomEditor(Gender.class, new GenderEditor());

}

Next, look at the method that handles GET requests. This method

resets the potentially submitted data by creating a new PersonTo

object and storing it in session. It requests the registration name

form to be displayed. (The forms code will soon follow)

@RequestMapping(method = RequestMethod.GET)

public String setupForm(Model model) {

PersonTo personTo = new PersonTo();

model.addAttribute(PERSON_TO, personTo);

return REGISTRATION_NAME_FORM;

B L O G A R C H I V E

► 2013 (11)

► 2012 (33)

▼ 2011 (27)

► December (3)

► November (1)

▼ October (3)

Wizard form with Spring MVC

JEE6: Integration testing with

JBoss 7

jQuery UI Autocomplete +

Spring MVC

► September (2)

► August (1)

► July (3)

► May (9)

► April (2)

► March (3)

► 2010 (53)

S E A R C H T H I S B L O G

Loading...


2 of 7 6/30/2013 1:57 PM

}

And now the big thing. The method that handles POST requests

which are those where the user actually submitted data.

@RequestMapping(method = RequestMethod.POST)

public String submitForm(HttpServletRequest request,

HttpServletResponse response,

@ModelAttribute(PERSON_TO) PersonTo personTo, BindingResult re

SessionStatus status, @RequestParam("_page") int currentPage,

Model model) {

Map<Integer, String> pageForms = new HashMap<Integer, String>();

pageForms.put(0, REGISTRATION_NAME_FORM);

pageForms.put(1, REGISTRATION_GENDER_FORM);

if (userClickedCancel(request)) {

status.setComplete();

return REDIRECT_TO_HOMEPAGE;

} else if (userIsFinished(request)) {

validator.validate(personTo, result);

if (result.hasErrors()) {

return pageForms.get(currentPage);

} else {

log.info("Registration finished for person [{}: {}].",

personTo.getGender(), personTo.getName());

personTo.setRegistrationComplete(true);

return REDIRECT_TO_SUCCESS_PAGE;

}

} else {

int targetPage = WebUtils.getTargetPage(request, "_target",

currentPage);

if (userClickedPrevious(currentPage, targetPage)) {

return pageForms.get(targetPage);

} else {

switch (currentPage) {

case 0:

validator.validateName(personTo, result);

break;

}

case 1:

validator.validateGender(personTo, result);

break;

}

if (result.hasErrors()) {


3 of 7 6/30/2013 1:57 PM

return pageForms.get(currentPage);

} else {

return pageForms.get(targetPage);

}

}

}

}

If the user clicked cancel, cancel the whole thing by ending

the session and redirect to the home page.

1.

If the user is finished, validate the whole session stored

transfer object. Redirect to success page or display errors.

2.

Otherwise, this is another step in the wizard. In that case,

establish which step it is and apply correct validation. If there

are errors, show the current page where Spring will display

error messages. If everything is OK, go to the next page.

3.

View

I'm using Velocity. Here's the first form where the user types their

name. Look at the Next and Cancel buttons (the names are

important, _target1 and _cancel) and at the hidden input with page

number (zero, since this is the first page in the wizard).

<form method="post" modelAttribute="personTo">

<table>

<tr>

<td>Your name:</td>

<td>#springFormInput("personTo.name" "")

</td>

<td>#springShowErrors("" "")

</td>

</tr>

<tr>

<td colspan="3">

<input type="submit" value="Next" name="_target1">

<input type="submit" value="Cancel" name="_cancel"

<input type="hidden" value="0" name="_page">

</td>

</tr>

</table>

</form>

And the gender selection page. Note we are using a drop down list

here.

<form method="post" modelAttribute="personTo">

<table>


4 of 7 6/30/2013 1:57 PM

<tr>

<td>Your gender:</td>

<td>#springFormSingleSelect("personTo.gender" $genders

</td>

<td>#springShowErrors("" "")

</td>

</tr>

<tr>

<td colspan="3">

<input type="submit" value="Previous" name="_targe

<input type="submit" value="Finish" name="_finish"

<input type="submit" value="Cancel" name="_cancel"

<input type="hidden" value="1" name="_page">

</td>

</tr>

</table>

</form>

Property editor

Here's the GenderEditor, if you're interested.

public class GenderEditor extends PropertyEditorSupport {

@Override

public String getAsText() {

if (getValue() == null) {

return null;

} else {

Gender gender = (Gender) getValue();

return gender.toString();

}

}

@Override

public void setAsText(String text) throws IllegalArgumentException {

if (StringUtils.isEmpty(text)) {

setValue("");

} else if (text.equalsIgnoreCase("m")) {

setValue(Gender.MALE);

} else if (text.equalsIgnoreCase("f")) {

setValue(Gender.FEMALE);

} else if (text.equalsIgnoreCase("o")) {

setValue(Gender.OTHER);

}

}


5 of 7 6/30/2013 1:57 PM

Newer Post Older Post

}

We need the getAsText() method for validation purposes. That

makes sure that if an unknown value is passed from the view, the

resulting value is null (as opposed to the String "null").

Download the source code

The source code for this is available on GitHub.

POSTED BY M ICHAŁ HUN IEW ICZ AT 7:47 PM

LABELS: JAVA, PROGRAMMING, SPR ING, VELOCITY

2 C O M M E N T S :

Add comment

Comment as:

Home

Subscribe to: Post Comments (Atom)

Rossen Stoyanchev November 1, 2011 at 3:18 PM

This is a good case for using Spring Web Flow. If yourapplication has a few of these wizards.

Reply

Michał Huniewicz November 1, 2011 at 11:35 PM

Hi Rossen, thanks for your comment. I am going to look intoSpring Web Flow in future.

Reply


6 of 7 6/30/2013 1:57 PM


7 of 7 6/30/2013 1:57 PM

wizard form with spring mvc

Documents