Question

I have written a custom Validator that expects an attribute to be set. I know I have to write a Handler (TagHandler or ValidatorHandler?) to set that attribute, but I am having trouble doing it.

<tag>
    <tag-name>validateCustom</tag-name>
    <validator>
        <validator-id>package.CUSTOM_VALIDATOR</validator-id>
    </validator>
</tag>

Where do i put the handler-class element? And how do I write the handler so that it will pass the attributes to my custom validator?

Thanks in advance!

Answer 1

Here is a validator with custom attribute skeleton:

public class CustomValidator implements Validator, Serializable
{
    private static final long serialVersionUID = ...;
    private String someAttribute;

    public void setSomeAttribute(String someAttribute)
    {
        this.someAttribute = someAttribute;
    }

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

Here is the tag handler:

public class CustomValidatorHandler extends ValidateHandler
{
    private final TagAttribute someAttribute;

    public CustomValidatorHandler(ValidatorConfig config)
    {
        super(config);

        someAttribute = this.getAttribute("someAttribute");
    }

    @Override
    protected Validator createValidator(FaceletContext ctx)
    {
        CustomValidator result = (CustomValidator) ctx
        .getFacesContext()
        .getApplication()
        .createValidator("package.CUSTOM_VALIDATOR");

        if (someAttribute != null) result.setSomeAttribute(someAttribute.getValue(ctx));

        return result;
    }
}

And here is part of the taglib file:

<tag>
    <tag-name>validateCustom</tag-name>
    <validator>
        <validator-id>package.CUSTOM_VALIDATOR</validator-id>
    <handler-class>package.CustomValidatorHandler</handler-class>
    </validator>
</tag>