Displaying Spring MVC validation errors in Freemar

问题:

I'm trying to display a list of global validation errors in my freemarker template if a controller returns binding errors. I can display errors that are associated with a field, but I want to detect when an error has occurred within a specific bean and display a message at the top of the page. I've tried using the example below which produces no output:

<@spring.bind "webPage" />
....
<#if spring.status.error>
There were problems with the data you entered:
<ul>
<#list spring.status.errorMessages as error>
<li>${error?html}</li>
</#list>
</ul>
</#if>

The line below always returns 0, despite there being errors with the submitted form:

${spring.status.errorMessages?size}

My controller code is below:

@RequestMapping(method = RequestMethod.POST)
public ModelAndView save(@ModelAttribute("webPage") @Valid WebPage page, BindingResult result, Model model) {
    if (!model.containsAttribute("site")) {
        throw new IllegalArgumentException("Model must contain site attribute.");
    }
    Site site = (Site) model.asMap().get("site");
    if (!result.hasErrors() && !page.isNew()) {
        this.pageService.save(page, site);
    } else if (!result.hasErrors() && page.isNew()) {
        this.pageService.create(page, site);
    } 
    return createMav(result);
}

The createMav method is below:

public ModelAndView createMav(BindingResult result) {
    ModelAndView mav = new ModelAndView();
    mav.setViewName(getPrimaryControllerView());
    mav.addAllObjects(result.getModel());
    return mav;
}

Is there a way to achieve this using Freemarker + Spring MVC?

回答1:

I found a roundabout way to do this using the standard MVC JSP taglib. I make this available to Freemarker:

<#assign form=JspTaglibs["http://www.springframework.org/tags/form"] />

I then use the following macro to display global error message:

<#macro formErrors>
    <#assign formErrors><@form.errors path="*" /></#assign>
    <#if formErrors?has_content>
        <div id="errors">
            <@spring.message "admin.error.globalMessage" />
        </div>
    </#if>
</#macro>

I just place the following line where ever I want this error message to appear (this has to be contained within the form element that submits to the controller):

<@form.form method="POST" commandName="webPage">

            <@formErrors />                        
            ....
</@form.form>

回答2:

You can write as follows:

<#if spring.status.error>
<ul>
   <#list spring.status.errors.globalErrors as error>
   <li>${error.defaultMessage}</li>   
   </#list>
</ul>
</#if>

More info at BindStatus and Errors classes.

回答3:

Try something like this:

<@spring.bind "webPage" />
<#if (spring.status.errors.allErrors?size > 0) >
    <@spring.message "my.global.error.code"/>
</#if>

回答4:

See the documentation: http://static.springsource.org/spring/docs/current/spring-framework-reference/html/view.html#view-velocity-forms. It has an example of what you want to do.