javax.faces.validator.Validator Maven / Gradle / Ivy
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/*
* Copyright (c) 1997, 2018 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 javax.faces.validator;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import java.util.EventListener;
/**
* A Validator
* implementation is a class that can perform validation (correctness
* checks) on a {@link javax.faces.component.EditableValueHolder}. Zero
* or more Validators can be associated with each {@link
* javax.faces.component.EditableValueHolder} in the view, and are
* called during the Process Validations phase of the request
* processing lifecycle.
*
* Individual {@link Validator}s should examine the value and
* component that they are passed, and throw a {@link ValidatorException}
* containing a {@link javax.faces.application.FacesMessage}, documenting
* any failures to conform to the required rules.
*
*
For maximum generality, {@link Validator} instances may be
* configurable based on properties of the {@link Validator} implementation
* class. For example, a range check {@link Validator} might support
* configuration of the minimum and maximum values to be used.
*
* {@link Validator} implementations must have a zero-arguments
* public constructor. In addition, if the {@link Validator} class
* wishes to have configuration property values saved and restored with
* the view, the implementation must also implement {@link
* javax.faces.component.StateHolder}.
* If the class implementing
* Validator has a {@link
* javax.faces.application.ResourceDependency} annotation, the action
* described in ResourceDependency must be taken when
* {@link javax.faces.component.EditableValueHolder#addValidator} is
* called. If the class implementing Validator has a {@link
* javax.faces.application.ResourceDependencies} annotation, the
* action described in ResourceDependencies must be taken
* when {@link javax.faces.component.EditableValueHolder#addValidator}
* is called.
*
* @param The generic type of object value to validate.
*/
public interface Validator extends EventListener {
/**
* The message identifier of the {@link javax.faces.application.FacesMessage} to be created if
* the maximum or minimum value check fails, and both the maximum
* and minimum values for this validator have been set. The message
* format string for this message may optionally include a
* {0} placeholder, which will be replaced by the
* configured minimum value, and a {1} placeholder,
* which will be replaced by the configured maximum value.
*
* @deprecated Use {@link DoubleRangeValidator#NOT_IN_RANGE_MESSAGE_ID} or
* {@link LongRangeValidator#NOT_IN_RANGE_MESSAGE_ID} instead.
*/
public static final String NOT_IN_RANGE_MESSAGE_ID =
"javax.faces.validator.NOT_IN_RANGE";
/**
* Perform the
* correctness checks implemented by this {@link Validator} against
* the specified {@link UIComponent}. If any violations are found,
* a {@link ValidatorException} will be thrown containing the {@link
* javax.faces.application.FacesMessage} describing the failure.
*
*
*
* For a validator to be fully compliant with Version 2 and later
* of the specification, it must not fail validation on
* null or empty values unless it is specifically
* intended to address null or empty values. An
* application-wide <context-param> is provided
* to allow validators designed for Jakarta Server Faces 1.2 to work
* with Jakarta Server Faces 2 and later.
* The javax.faces.VALIDATE_EMPTY_FIELDS
* <context-param> must be set to
* false to enable this backwards compatibility
* behavior.
*
*
*
* @param context FacesContext for the request we are processing
* @param component UIComponent we are checking for correctness
* @param value the value to validate
* @throws ValidatorException if validation fails
* @throws NullPointerException if context
* or component is null
*/
public void validate(FacesContext context,
UIComponent component,
T value) throws ValidatorException;
}