Question

我有一种情况，我需要覆盖或扩展默认的必需验证器，以便我可以在缺少所需的值时在服务器端执行多个操作。

我只是通过扩展标准的RequiredValidator来尝试它，但是当提交的值不为null时，验证器才会被触发：

import static com.util.ResourceBundleHelper.getMessage;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.validator.FacesValidator;
import javax.faces.validator.RequiredValidator;
import javax.faces.validator.ValidatorException;
import org.omnifaces.util.Ajax;

@FacesValidator("com.util.validator.AjaxRequiredValidator")
public class AjaxRequiredValidator extends RequiredValidator {

   @Override
   public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException {

     //need to perform additional logic here, depending on the actual component parameter

     if (value == null || value.toString().isEmpty()){          
         String javascriptMethod = "MODULE.error(" + component.getId() +  ")";          
         Ajax.oncomplete(javascriptMethod);
         throw new ValidatorException(getMessage("error"));
     }
   }
}

XHTML：

<h:inputText value="#{bean.requiredValue}">
 <f:validator validatorId="com.util.validator.AjaxRequiredValidator"/>
</h:inputText>

我读到了context-param：

 <context-param>
    <param-name>javax.faces.VALIDATE_EMPTY_FIELDS</param-name>
    <param-value>true</param-value>
 </context-param>

但我不想全局设置此行为，仅针对特定组件。这可能吗？

为什么/如何在我使用时触发默认验证器：

<h:inputText value="#{bean.requiredValue}" required="true"/>

Answer 1

因为它没有受到伤害，所以我去了web.xml中的context-param解决方案：

<context-param>
   <param-name>javax.faces.VALIDATE_EMPTY_FIELDS</param-name>
   <param-value>true</param-value>
</context-param>

 <h:inputText value="#{bean.requiredValue}" validator="#{bean.validateRequired}"/>

public interface RequiredValidation {

    default public void validateRequired(FacesContext context, UIComponent component, Object value) {
        if (value == null || value.toString().isEmpty()){          
             String javascriptMethod = "MAINMODULE.error(" + component.getId() +  ")";               
             throw new AjaxValidatorException(javascriptMethod,"fieldRequired");
        }
    }       
}   

@ManagedBean
@ViewScoped
public class Bean implements RequiredValidation {

    private String requiredValue;
    //...

}

JSF 2.2：扩展/覆盖默认的必需验证器

1 个答案: