Java example source code file (ValidationEventHandler.java)

This example Java source code file (ValidationEventHandler.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

validationevent, validationeventhandler

The ValidationEventHandler.java Java example source code

/*
 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package javax.xml.bind;

/**
 * A basic event handler interface for validation errors.
 *
 * <p>
 * If an application needs to implement customized event handling, it must
 * implement this interface and then register it with either the
 * {@link Unmarshaller#setEventHandler(ValidationEventHandler) Unmarshaller},
 * the {@link Validator#setEventHandler(ValidationEventHandler) Validator}, or
 * the {@link Marshaller#setEventHandler(ValidationEventHandler) Marshaller}.
 * The JAXB Provider will then report validation errors and warnings encountered
 * during the unmarshal, marshal, and validate operations to these event
 * handlers.
 *
 * <p>
 * If the <tt>handleEvent method throws an unchecked runtime exception,
 * the JAXB Provider must treat that as if the method returned false, effectively
 * terminating whatever operation was in progress at the time (unmarshal,
 * validate, or marshal).
 *
 * <p>
 * Modifying the Java content tree within your event handler is undefined
 * by the specification and may result in unexpected behaviour.
 *
 * <p>
 * Failing to return false from the <tt>handleEvent method after
 * encountering a fatal error is undefined by the specification and may result
 * in unexpected behavior.
 *
 * <p>
 * <b>Default Event Handler
 * <blockquote>
 *    See: <a href="Validator.html#defaulthandler">Validator javadocs
 * </blockquote>
 *
 * @author <ul>
Ryan Shoemaker, Sun Microsystems, Inc.
Kohsuke Kawaguchi, Sun Microsystems, Inc.
Joe Fialli, Sun Microsystems, Inc.
 * @see Unmarshaller
 * @see Validator
 * @see Marshaller
 * @see ValidationEvent
 * @see javax.xml.bind.util.ValidationEventCollector
 * @since JAXB1.0
 */
public interface ValidationEventHandler {
    /**
     * Receive notification of a validation warning or error.
     *
     * The ValidationEvent will have a
     * {@link ValidationEventLocator ValidationEventLocator} embedded in it that
     * indicates where the error or warning occurred.
     *
     * <p>
     * If an unchecked runtime exception is thrown from this method, the JAXB
     * provider will treat it as if the method returned false and interrupt
     * the current unmarshal, validate, or marshal operation.
     *
     * @param event the encapsulated validation event information.  It is a
     * provider error if this parameter is null.
     * @return true if the JAXB Provider should attempt to continue the current
     *         unmarshal, validate, or marshal operation after handling this
     *         warning/error, false if the provider should terminate the current
     *         operation with the appropriate <tt>UnmarshalException,
     *         <tt>ValidationException, or MarshalException.
     * @throws IllegalArgumentException if the event object is null.
     */
    public boolean handleEvent( ValidationEvent event );

}