javax.faces.webapp.ValidatorTag Maven / Gradle / Ivy
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package javax.faces.webapp;
import javax.el.ValueExpression;
import javax.faces.component.EditableValueHolder;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.validator.Validator;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;
/**
* ValidatorTag is a base class for all JSP custom actions
* that create and register a Validator
instance on the
* {@link EditableValueHolder} associated with our most immediate surrounding instance
* of a tag whose implementation class is a subclass of {@link UIComponentTag}.
* To avoid creating duplicate instances when a page is redisplayed,
* creation and registration of a {@link Validator} occurs
* only if the corresponding {@link UIComponent} was
* created (by the owning {@link UIComponentTag}) during the execution of the
* current page.
*
* This class may be used directly to implement a generic validator
* registration tag (based on the validator-id specified by the
* id
attribute), or as a base class for tag instances that
* support specific {@link Validator} subclasses. This id
* attribute must refer to one of the well known validator-ids, or a
* custom validator-id as defined in a faces-config.xml
* file.
*
* Subclasses of this class must implement the
* createValidator()
method, which creates and returns a
* {@link Validator} instance. Any configuration properties that specify
* the limits to be enforced by this {@link Validator} must have been
* set by the createValidator()
method. Generally, this occurs
* by copying corresponding attribute values on the tag instance.
*
* This tag creates no output to the page currently being created. It
* is used solely for the side effect of {@link Validator} creation.
*
* @deprecated This has been partially replaced by {@link
* ValidatorELTag}. The remainder of the functionality, namely, the
* binding facility and the implementation of the {@link
* #createValidator} method, is now an implementation detail.
*/
public class ValidatorTag extends TagSupport {
// ---------------------------------------------------------- Static Members
private static final long serialVersionUID = -5562623615418158868L;
// ------------------------------------------------------------- Attributes
/**
* The identifier of the {@link Validator} instance to be created.
*/
private String validatorId = null;
/**
* The {@link ValueExpression} that evaluates to an object that
* implements {@link Validator}.
*/
private String binding = null;
/**
* Set the identifer of the {@link Validator} instance to be created.
*
* @param validatorId The new identifier of the validator instance to be
* created.
*/
public void setValidatorId(String validatorId) {
this.validatorId = validatorId;
}
/**
*
Set the expression that will be used to create a {@link ValueExpression}
* that references a backing bean property of the {@link Validator} instance to
* be created.
*
* @param binding The new expression
*
* @throws JspException if a JSP error occurs
*/
public void setBinding(String binding)
throws JspException {
if (binding != null && !UIComponentTag.isValueReference(binding)) {
//PENDING i18n
throw new JspException("Invalid Expression:"+binding);
}
this.binding = binding;
}
// --------------------------------------------------------- Public Methods
/**
* Create a new instance of the specified {@link Validator}
* class, and register it with the {@link UIComponent} instance associated
* with our most immediately surrounding {@link UIComponentTag} instance, if
* the {@link UIComponent} instance was created by this execution of the
* containing JSP page.
*
* @throws JspException if a JSP error occurs
*/
public int doStartTag() throws JspException {
// Locate our parent UIComponentTag
UIComponentClassicTagBase tag =
UIComponentClassicTagBase.getParentUIComponentClassicTagBase(pageContext);
if (tag == null) {
//PENDING i18n
throw new JspException("Not nested in a UIComponentTag Error for tag with handler class:"+
this.getClass().getName());
}
// Nothing to do unless this tag created a component
if (!tag.getCreated()) {
return (SKIP_BODY);
}
UIComponent component = tag.getComponentInstance();
if (component == null) {
//PENDING i18n
throw new JspException("Can't create Component from tag.");
}
if (!(component instanceof EditableValueHolder)) {
// PENDING i18n
throw new JspException("Not nested in a tag of proper type. Error for tag with handler class:"+
this.getClass().getName());
}
Validator validator = createValidator();
if (validator == null) {
//noinspection NonConstantStringShouldBeStringBuffer
String validateError = null;
if (binding != null) {
validateError = binding;
}
if (validatorId != null) {
if (validateError != null) {
validateError += " or " + validatorId;
} else {
validateError = validatorId;
}
}
// PENDING i18n
throw new JspException("Can't create class of type:"+
"javax.faces.validator.Validator from:"+validateError);
}
// Register an instance with the appropriate component
((EditableValueHolder)component).addValidator(validator);
return (SKIP_BODY);
}
/**
* Release references to any acquired resources.
*/
public void release() {
this.id = null;
}
// ------------------------------------------------------ Protected Methods
/**
*
Create and return a new {@link Validator} to be registered
* on our surrounding {@link UIComponent}.
*
* @throws JspException if a new instance cannot be created
*/
protected Validator createValidator()
throws JspException {
FacesContext context = FacesContext.getCurrentInstance();
Validator validator = null;
ValueExpression vb = null;
// If "binding" is set, use it to create a validator instance.
if (binding != null) {
try {
vb = context.getApplication().getExpressionFactory().createValueExpression(context.getELContext(),
binding, Object.class);
if (vb != null) {
validator = (Validator)vb.getValue(context.getELContext());
if (validator != null) {
return validator;
}
}
} catch (Exception e) {
throw new JspException(e);
}
}
// If "validatorId" is set, use it to create the validator
// instance. If "validatorId" and "binding" are both set, store the
// validator instance in the value of the property represented by
// the value binding expression.
if (validatorId != null) {
try {
String validatorIdVal = validatorId;
if (UIComponentTag.isValueReference(validatorId)) {
ValueExpression idBinding = context.getApplication().
getExpressionFactory().createValueExpression(context.getELContext(),
validatorId, Object.class);
validatorIdVal = (String)idBinding.getValue(context.getELContext());
}
validator = context.getApplication().createValidator(validatorIdVal);
if (validator != null) {
if (vb != null) {
vb.setValue(context.getELContext(), validator);
}
}
} catch (Exception e) {
throw new JspException(e);
}
}
return validator;
}
}