vraptor-form

#VRaptor-form

#Installing

Add to your pom:

    <dependency>
    	<groupId>br.com.caelum.vraptor</groupId>
    	<artifactId>vraptor-form</artifactId>
    	<version>4.0.0-SNAPSHOT</version>
    </dependency>
    

#Basic validation and mass assignment protection

@Controller
public class UsersController {
  @Inject
	private Form<User> userForm;
	  
	public void add(User user) {  
	  userForm.bind(user);
	  userForm.navigate().onErrorUsePageOf(HomeController.class).index();
	  
	  //rest of the code here
  }
}

If you need to protect against Mass assignment, you can use hasBlackListedFields or hasOnlyAllowedFields.

    public void add(User user) {  
      userForm.bind(user);
      
  		if (userForm.hasBlackListedFields("user.admin")) {
  			userForm.reject("invalid.params", "Invalid paramters came from your form");
  		}
      
      
      userForm.navigate().onErrorUsePageOf(HomeController.class).index();
  
      //rest of the code here
    }

#Errors in your view

    <c:if test="${form.hasErrors()}">
    	<div class="alert alert-danger">
    		<button type="button" class="close" data-dismiss="alert">&times;</button>
    		<c:forEach items="${form.allErrors}" var="error">
    			<b><fmt:message key="${error.category}" /></b> - ${error.message}
    		</c:forEach>
    	</div>
    </c:if>

If you need, you can access specific field errors:

  ${userForm.get("login").getErrors()}