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org.springframework.web.servlet.mvc
public class: SimpleFormController [javadoc | source]

java.lang.Object
   org.springframework.context.support.ApplicationObjectSupport
      org.springframework.web.context.support.WebApplicationObjectSupport
         org.springframework.web.servlet.support.WebContentGenerator
            org.springframework.web.servlet.mvc.AbstractController
               org.springframework.web.servlet.mvc.BaseCommandController
                  org.springframework.web.servlet.mvc.AbstractFormController
                     org.springframework.web.servlet.mvc.SimpleFormController

All Implemented Interfaces:
    Controller, ServletContextAware, ApplicationContextAware

Direct Known Subclasses:
    CancellableFormController

Concrete FormController implementation that provides configurable form and success views, and an onSubmit chain for convenient overriding. Automatically resubmits to the form view in case of validation errors, and renders the success view in case of a valid submission.

The workflow of this Controller does not differ much from the one described in the AbstractFormController . The difference is that you do not need to implement showForm and processFormSubmission : A form view and a success view can be configured declaratively.

Workflow (in addition to the superclass):

1. Call to processFormSubmission which inspects the Errors object to see if any errors have occurred during binding and validation.
2. If errors occured, the controller will return the configured formView, showing the form again (possibly rendering according error messages).
3. If isFormChangeRequest is overridden and returns true for the given request, the controller will return the formView too. In that case, the controller will also suppress validation. Before returning the formView, the controller will invoke #onFormChange , giving sub-classes a chance to make modification to the command object. This is intended for requests that change the structure of the form, which should not cause validation and show the form in any case.
4. If no errors occurred, the controller will call onSubmit using all parameters, which in case of the default implementation delegates to onSubmit with just the command object. The default implementation of the latter method will return the configured successView. Consider implementing #doSubmitAction doSubmitAction for simply performing a submit action and rendering the success view.

The submit behavior can be customized by overriding one of the onSubmit methods. Submit actions can also perform custom validation if necessary (typically database-driven checks), calling showForm in case of validation errors to show the form view again.

Exposed configuration properties (and those defined by superclass):

name	default	description
formView	null	Indicates what view to use when the user asks for a new form or when validation errors have occurred on form submission.
successView	null	Indicates what view to use when successful form submissions have occurred. Such a success view could e.g. display a submission summary. More sophisticated actions can be implemented by overriding one of the onSubmit() methods.

author: Juergen - Hoeller

author: Rob - Harrop

since: 05.05.2003 -

Fields inherited from org.springframework.web.servlet.mvc.BaseCommandController:
DEFAULT_COMMAND_NAME

Fields inherited from org.springframework.web.servlet.support.WebContentGenerator:
METHOD_GET,  METHOD_HEAD,  METHOD_POST

Fields inherited from org.springframework.context.support.ApplicationObjectSupport:
logger

Constructor:

public SimpleFormController() { // AbstractFormController sets default cache seconds to 0. super(); } Create a new SimpleFormController. Subclasses should set the following properties, either in the constructor or via a BeanFactory: commandName, commandClass, sessionForm, formView, successView. Note that commandClass doesn't need to be set when overriding formBackingObject, as this determines the class anyway. Also see: setCommandClass setCommandName setSessionForm setFormView setSuccessView formBackingObject

Method from org.springframework.web.servlet.mvc.SimpleFormController Summary:
doSubmitAction,   getFormView,   getSuccessView,   isFormChangeRequest,   isFormChangeRequest,   onFormChange,   onFormChange,   onSubmit,   onSubmit,   onSubmit,   processFormSubmission,   referenceData,   referenceData,   setFormView,   setSuccessView,   showForm,   showForm,   suppressValidation

Methods from org.springframework.web.servlet.mvc.AbstractFormController:

currentFormObject,   formBackingObject,   getCommand,   getErrorsForNewForm,   getFormSessionAttributeName,   getFormSessionAttributeName,   handleInvalidSubmit,   handleRequestInternal,   isBindOnNewForm,   isFormSubmission,   isSessionForm,   onBindOnNewForm,   onBindOnNewForm,   processFormSubmission,   referenceData,   setBindOnNewForm,   setSessionForm,   showForm,   showForm,   showForm,   showNewForm

Methods from org.springframework.web.servlet.mvc.BaseCommandController:

bindAndValidate,   checkCommand,   createBinder,   createCommand,   getBindingErrorProcessor,   getCommand,   getCommandClass,   getCommandName,   getMessageCodesResolver,   getPropertyEditorRegistrars,   getValidator,   getValidators,   getWebBindingInitializer,   initApplicationContext,   initBinder,   isValidateOnBinding,   onBind,   onBind,   onBindAndValidate,   prepareBinder,   setBindingErrorProcessor,   setCommandClass,   setCommandName,   setMessageCodesResolver,   setPropertyEditorRegistrar,   setPropertyEditorRegistrars,   setValidateOnBinding,   setValidator,   setValidators,   setWebBindingInitializer,   suppressBinding,   suppressValidation,   suppressValidation,   suppressValidation,   useDirectFieldAccess

Methods from org.springframework.web.servlet.mvc.AbstractController:
handleRequest,   handleRequestInternal,   isSynchronizeOnSession,   setSynchronizeOnSession

Methods from org.springframework.web.servlet.support.WebContentGenerator:

applyCacheSeconds,   applyCacheSeconds,   cacheForSeconds,   cacheForSeconds,   checkAndPrepare,   checkAndPrepare,   getCacheSeconds,   getSupportedMethods,   isRequireSession,   isUseCacheControlHeader,   isUseCacheControlNoStore,   isUseExpiresHeader,   preventCaching,   setCacheSeconds,   setRequireSession,   setSupportedMethods,   setUseCacheControlHeader,   setUseCacheControlNoStore,   setUseExpiresHeader

Methods from org.springframework.web.context.support.WebApplicationObjectSupport:
getServletContext,   getTempDir,   getWebApplicationContext,   initApplicationContext,   initServletContext,   isContextRequired,   setServletContext

Methods from org.springframework.context.support.ApplicationObjectSupport:
getApplicationContext,   getMessageSourceAccessor,   initApplicationContext,   initApplicationContext,   isContextRequired,   requiredContextClass,   setApplicationContext

Methods from java.lang.Object:
equals,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait

Method from org.springframework.web.servlet.mvc.SimpleFormController Detail:
protected void doSubmitAction(Object command) throws Exception { } Template method for submit actions. Called by the default implementation of the simplest #onSubmit(Object) variant. This is the preferred submit callback to implement if you want to perform an action (like storing changes to the database) and then render the success view with the command and Errors instance as model. You don't need to care about the success ModelAndView here.
public final String getFormView() { return this.formView; } Return the name of the view that should be used for form display.
public final String getSuccessView() { return this.successView; } Return the name of the view that should be shown on successful submit.
protected boolean isFormChangeRequest(HttpServletRequest request) { return false; } Simpler isFormChangeRequest variant, called by the full variant #isFormChangeRequest(HttpServletRequest, Object) . The default implementation returns false
protected boolean isFormChangeRequest(HttpServletRequest request, Object command) { return isFormChangeRequest(request); } Determine whether the given request is a form change request. A form change request changes the appearance of the form and should always show the new form, without validation. Gets called by #suppressValidation and #processFormSubmission . Consequently, this single method determines to suppress validation and to show the form view in any case. The default implementation delegates to #isFormChangeRequest(javax.servlet.http.HttpServletRequest) .
protected void onFormChange(HttpServletRequest request, HttpServletResponse response, Object command) throws Exception { } Simpler onFormChange variant, called by the full variant #onFormChange(HttpServletRequest, HttpServletResponse, Object, BindException) . The default implementation is empty.
protected void onFormChange(HttpServletRequest request, HttpServletResponse response, Object command, BindException errors) throws Exception { onFormChange(request, response, command); } Called during form submission if #isFormChangeRequest(javax.servlet.http.HttpServletRequest) returns true. Allows subclasses to implement custom logic to modify the command object to directly modify data in the form. The default implementation delegates to #onFormChange(HttpServletRequest, HttpServletResponse, Object, BindException) .
protected ModelAndView onSubmit(Object command) throws Exception { doSubmitAction(command); return null; } Simplest onSubmit variant. Called by the default implementation of the #onSubmit(Object, BindException) variant. This implementation calls #doSubmitAction(Object) and returns null as ModelAndView, making the calling onSubmit method perform its default rendering of the success view. Subclasses can override this to provide custom submission handling that just depends on the command object. It's preferable to use either #onSubmit(Object, BindException) or #doSubmitAction(Object) , though: Use the former when you want to build your own ModelAndView; use the latter when you want to perform an action and forward to the successView.
protected ModelAndView onSubmit(Object command, BindException errors) throws Exception { ModelAndView mv = onSubmit(command); if (mv != null) { // simplest onSubmit variant implemented in custom subclass return mv; } else { // default behavior: render success view if (getSuccessView() == null) { throw new ServletException("successView isn't set"); } return new ModelAndView(getSuccessView(), errors.getModel()); } } Simpler onSubmit variant. Called by the default implementation of the #onSubmit(HttpServletRequest, HttpServletResponse, Object, BindException) variant with all parameters. The default implementation calls #onSubmit(Object) , using the returned ModelAndView if actually implemented in a subclass. Else, the default behavior will apply: rendering the success view with the command and Errors instance as model. Subclasses can override this to provide custom submission handling that does not need request and response. Call errors.getModel() to populate the ModelAndView model with the command and the Errors instance, under the specified command name, as expected by the "spring:bind" tag.
protected ModelAndView onSubmit(HttpServletRequest request, HttpServletResponse response, Object command, BindException errors) throws Exception { return onSubmit(command, errors); } Submit callback with all parameters. Called in case of submit without errors reported by the registered validator, or on every submit if no validator. The default implementation delegates to #onSubmit(Object, BindException) . For simply performing a submit action and rendering the specified success view, consider implementing #doSubmitAction rather than an onSubmit variant. Subclasses can override this to provide custom submission handling like storing the object to the database. Implementations can also perform custom validation and call showForm to return to the form. Do not implement multiple onSubmit methods: In that case, just this method will be called by the controller. Call errors.getModel() to populate the ModelAndView model with the command and the Errors instance, under the specified command name, as expected by the "spring:bind" tag.
protected ModelAndView processFormSubmission(HttpServletRequest request, HttpServletResponse response, Object command, BindException errors) throws Exception { if (errors.hasErrors()) { if (logger.isDebugEnabled()) { logger.debug("Data binding errors: " + errors.getErrorCount()); } return showForm(request, response, errors); } else if (isFormChangeRequest(request, command)) { logger.debug("Detected form change request - > routing request to onFormChange"); onFormChange(request, response, command, errors); return showForm(request, response, errors); } else { logger.debug("No errors - > processing submit"); return onSubmit(request, response, command, errors); } } This implementation calls #showForm(HttpServletRequest, HttpServletResponse, BindException) in case of errors, and delegates to the full #onSubmit(HttpServletRequest, HttpServletResponse, Object, BindException) 's variant else. This can only be overridden to check for an action that should be executed without respect to binding errors, like a cancel action. To just handle successful submissions without binding errors, override one of the onSubmit methods or #doSubmitAction .
protected Map referenceData(HttpServletRequest request) throws Exception { return null; } Create a reference data map for the given request. Called by the #referenceData(HttpServletRequest, Object, Errors) variant with all parameters. The default implementation returns null. Subclasses can override this to set reference data used in the view.
protected Map referenceData(HttpServletRequest request, Object command, Errors errors) throws Exception { return referenceData(request); } Create a reference data map for the given request and command, consisting of bean name/bean instance pairs as expected by ModelAndView. The default implementation delegates to #referenceData(HttpServletRequest) . Subclasses can override this to set reference data used in the view.
public final void setFormView(String formView) { this.formView = formView; } Set the name of the view that should be used for form display.
public final void setSuccessView(String successView) { this.successView = successView; } Set the name of the view that should be shown on successful submit.
protected ModelAndView showForm(HttpServletRequest request, HttpServletResponse response, BindException errors) throws Exception { return showForm(request, response, errors, null); } This implementation shows the configured form view, delegating to the analogous #showForm(HttpServletRequest, HttpServletResponse, BindException, Map) variant with a "controlModel" argument. Can be called within #onSubmit(HttpServletRequest, HttpServletResponse, Object, BindException) implementations, to redirect back to the form in case of custom validation errors (errors not determined by the validator). Can be overridden in subclasses to show a custom view, writing directly to the response or preparing the response before rendering a view. If calling showForm with a custom control model in subclasses, it's preferable to override the analogous showForm version with a controlModel argument (which will handle both standard form showing and custom form showing then).
protected ModelAndView showForm(HttpServletRequest request, HttpServletResponse response, BindException errors, Map controlModel) throws Exception { return showForm(request, errors, getFormView(), controlModel); } This implementation shows the configured form view. Can be called within #onSubmit(HttpServletRequest, HttpServletResponse, Object, BindException) implementations, to redirect back to the form in case of custom validation errors (errors not determined by the validator). Can be overridden in subclasses to show a custom view, writing directly to the response or preparing the response before rendering a view.
protected boolean suppressValidation(HttpServletRequest request, Object command) { return isFormChangeRequest(request, command); } This implementation delegates to #isFormChangeRequest(HttpServletRequest, Object) : A form change request changes the appearance of the form and should not get validated but just show the new form.