jakarta.faces.validator.RequiredValidator Maven / Gradle / Ivy

/*
 * Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package jakarta.faces.validator;

import jakarta.faces.application.FacesMessage;
import jakarta.faces.component.UIComponent;
import jakarta.faces.component.UIInput;
import jakarta.faces.context.FacesContext;

/**
 * 
 * A Validator that checks for an empty value in the same way that UIInput checks for a value. In fact, this validator
 * is equivalent to setting the required attribute on the input component to true.
 * 
 *
 * @since 2.0
 */
public class RequiredValidator implements Validator {

    /**
     * 
     * The standard converter id for this converter.
     * 
     */
    public static final String VALIDATOR_ID = "jakarta.faces.Required";

    /**
     *
     * 
     * Verify that the converted object value is not null.
     * 
     *
     * @param context {@inheritDoc}
     * @param component {@inheritDoc}
     * @param value {@inheritDoc}
     *
     * @throws ValidatorException {@inheritDoc}
     *
     */
    @Override
    public void validate(FacesContext context, UIComponent component, Object value) {

        if (UIInput.isEmpty(value)) {
            FacesMessage msg;
            String requiredMessageStr = null;
            if (component instanceof UIInput) {
                requiredMessageStr = ((UIInput) component).getRequiredMessage();
            }

            // respect the message string override on the component to emulate required="true" behavior
            if (requiredMessageStr != null) {
                msg = new FacesMessage(FacesMessage.SEVERITY_ERROR, requiredMessageStr, requiredMessageStr);
            } else {
                msg = MessageFactory.getMessage(context, UIInput.REQUIRED_MESSAGE_ID, MessageFactory.getLabel(context, component));
            }

            throw new ValidatorException(msg);
        }
    }

}