RichFaces 4: AJAX validation feedback

In my previous post I showed you how to create a simple Maven based RichFaces 4 project. In this post I will show you how to provide a nice dynamic status for JSR-303 validation that may take a long time (check if user name is unique for instance).

Download sample code

Please note that I’ve been working a bit on the sample app so it has changed a little from its previous version. Therefore if you want to look at the source, please download the new version of my sample Maven 3, RichFaces 4, JSF 2 app.

The form

    <h:form rendered="#{!sessionTracker.loggedIn}">
       <rich:panel>
           <h:panelGrid columns="3">
               <h:outputText value="#{msg['registration.email']}" />
               <h:inputText id="email" value="#{registrationBean.email}">
                   <rich:validator />
               </h:inputText>
               <rich:message for="email" />

               <h:outputText value="#{msg['registration.name']}" />
               <h:inputText id="name" value="#{registrationBean.name}"
                   status="nameStatus">
                   <rich:validator status="nameStatus" />
               </h:inputText>
               <h:panelGroup>
                   <a4j:status name="nameStatus"
                       startText="#{msg['registration.checkingName']}"
                       startStyle="background-color: FFA500" />
                   <rich:message for="name" />
               </h:panelGroup>

               <h:commandButton value="#{msg['registration.register']}"
                   action="#{registrationBean.register}" />
           </h:panelGrid>
       </rich:panel>
   </h:form>

Backing bean

    @NotNull(message = "{rf.name.notNull}")
   @Size(min = 2, message = "{rf.name.size}")
   @ValidUserName
   public String getName() {
       return name;
   }

Validation

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


public class ValidUserNameValidator implements
       ConstraintValidator<ValidUserName, String> {

   private Logger log = LoggerFactory.getLogger(ValidUserNameValidator.class);

   private String[] forbiddenNames = { "Michal", "Mikey", "Mickey", "M1key",
           "M1ckey" };

   @Override
   public void initialize(ValidUserName firstUpper) {
       // See JSR 303 Section 2.4.1 for sample implementation.
   }

   @Override
   public boolean isValid(String value, ConstraintValidatorContext context) {
       log.debug("Validating.");

       if (value == null || value.length() == 0) {
           return true;
       }

       // Let's simulate a costly operation.
       try {
           Thread.sleep(1000);
       } catch (InterruptedException e) {
           // TODO Auto-generated catch block
           e.printStackTrace();
       }

       return isNotForbidden(value);
   }

To see it working, download the source code. It expects you to run it on JBoss 6.0.0.Final.