spring - 如何在 Spring RedirectView 中添加对象

Question

我对 Spring 有点陌生，我想知道如何在 RedirectView 中 addOject 就像在 ModelAndView 中一样，我可以在其中添加可在 View 中使用的对象。

 mnv = new ModelAndView( FORM_URL );
        mnv.addObject( "wpassbook", passbook );
        return mnv;


RedirectView redirectView = new RedirectView( "/credit" + FORM_URL );
        return new ModelAndView( redirectView );

无论如何，这是整个方法:

    /**
 * Accepts POST request for this resource url.
 * 
 * @param formBean bean containing values entered by the user
 * @param bindingResult contains validation failure messages if form bean is invalid
 * @param request instance of HttpServletRequest created by the container
 * @return the presentation layer & model object with errors to be rendered if validation fails, if successful a
 *         redirect is done.
 */
@RequestMapping( value = { FORM_URL }, method = RequestMethod.POST )
public ModelAndView processData( @ModelAttribute( "bean" ) @Valid final HostFinancialRequest formBean,
                                 final BindingResult bindingResult, HttpServletRequest request, @RequestParam("passbook") String passbook )
{
    ModelAndView mnv = null;

    if ( request.getSession() == null )
    {
        mnv = new ModelAndView( "timeout.jsp" );
        // display session timeout page
        // add session timeout message error
        mnv.addObject( DepositsControllerUtil.VAR_ERROR_MESSAGE,
                       ErrorCode.BDS_USER_SESSION_TIMEOUT.getDescription() );
        return mnv;
    }

    // check if validation failed
    if ( bindingResult.hasErrors() )
    {
        mnv = new ModelAndView( FORMVIEW );
        // check if teller override boolean flag is to be enabled
        DepositsControllerUtil.checkTellerOverrideError( mnv, bindingResult );
        // add static values
        loadDefault( mnv.getModelMap() );
        // return to presentation layer with model that contains errors
        return mnv;
    }

    /* ======== Validation if successful, continue processing then do a redirect======= */

    // add required fields
    fieldGenerator.populateConstantHeader( formBean, request );

    // save transaction
    Journal journal = journalManagerImpl.saveJournal( formBean );

    // convert the id to be code before sending to host
    Currency currency = currencyManagerImpl.get( journal.getCurrency().getCurrCode() );
    formBean.setCurrency( Integer.valueOf( currency.getCurrCode() ) );

    // send to host
    Map<String, Object> returnMap = hostConnectionDelegate.invoke( formBean, wsBean );

    // get response from the returned map
    HostRequest response = HostConnectionDelegateUtil.getHostResponse( returnMap );

    accountPostingValidator.validate( response, bindingResult );

    // check if validation failed
    if ( bindingResult.hasErrors() )
    {
        mnv = new ModelAndView( FORMVIEW );
        // check if teller override boolean flag is to be enabled
        DepositsControllerUtil.checkTellerOverrideError( mnv, bindingResult );
        // add static values
        loadDefault( mnv.getModelMap() );

        mnv.addObject( "postingRestrictionCode", response.getPostingRestrictionCode() );
        // return to presentation layer with model that contains errors
        return mnv;

    }
    else
    {
        // update transaction table based on host response
        if ( !HostConnectionDelegateUtil.isApproved( response ) )
        {
            journal.setErrorCode( response.getErrorCode() );
            journal.setStatus( response.getStatus() );
        }
        else
        {
            journal.setStatus( response.getStatus() );

        }
        // save journal
        journalManagerImpl.saveJournal( journal );

        if ( request.getSession() != null )
        {
            // add response to session for the presentation layer to display
            // transaction results.
            request.getSession().setAttribute( "bean", response );
        }

        RedirectView redirectView = new RedirectView( "/credit" + FORM_URL );
        return new ModelAndView( redirectView );
    }

}

我想在下面的方法中实现上面的代码。

TIA。

Answer 1

要通过重定向传输数据，请使用 RedirectAttributes.addFlashAttribute(key, value) 。
从文档:

A RedirectAttributes model is empty when the method is called and is never used unless the method returns a redirect view name or a RedirectView.

After the redirect, flash attributes are automatically added to the model of the controller that serves the target URL.

public ModelAndView processData(
    @Valid final HostFinancialRequest formBean,
    final BindingResult bindingResult, 
    HttpServletRequest request, 
    @RequestParam String passbook,
    RedirectAttributes redirectAttributes) {
    
    // do work an then setup the redirect attributes
    
    redirectAttributes.addFlashAttribute("key", value);

    return new ModelAndView("redirect:/credit" + FORM_URL);
}