api/src/main/java/jakarta/xml/bind/helpers/DefaultValidationEventHandler.java

/*
 * Copyright (c) 2003, 2021 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0, which is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package jakarta.xml.bind.helpers;

import org.w3c.dom.Node;

import jakarta.xml.bind.ValidationEvent;
import jakarta.xml.bind.ValidationEventHandler;
import jakarta.xml.bind.ValidationEventLocator;
import java.net.URL;

/**
 * <p>
 * JAXB 1.0 only default validation event handler. This is the default
 * handler for all objects created from a JAXBContext that is managing
 * schema-derived code generated by a JAXB 1.0 binding compiler.
 *
 * <p>
 * This handler causes the unmarshal and validate operations to fail on the first
 * error or fatal error.
 *
 * <p>
 * This handler is not the default handler for Jakarta XML Binding mapped classes following
 * Jakarta XML Binding or later versions. Default validation event handling has changed
 * and is specified in  {@link jakarta.xml.bind.Unmarshaller} and
 * {@link jakarta.xml.bind.Marshaller}.
 *
 * @author <ul><li>Ryan Shoemaker, Sun Microsystems, Inc.</li></ul>
 * @see jakarta.xml.bind.Unmarshaller
 * @see jakarta.xml.bind.ValidationEventHandler
 * @since 1.6, JAXB 1.0
 */
public class DefaultValidationEventHandler implements ValidationEventHandler {

    public DefaultValidationEventHandler() {}

    @Override
    public boolean handleEvent( ValidationEvent event ) {

        if( event == null ) {
            throw new IllegalArgumentException();
        }

        // calculate the severity prefix and return value
        String severity = null;
        boolean retVal = false;
        switch ( event.getSeverity() ) {
            case ValidationEvent.WARNING:
                severity = Messages.format( Messages.WARNING );
                retVal = true; // continue after warnings
                break;
            case ValidationEvent.ERROR:
                severity = Messages.format( Messages.ERROR );
                retVal = false; // terminate after errors
                break;
            case ValidationEvent.FATAL_ERROR:
                severity = Messages.format( Messages.FATAL_ERROR );
                retVal = false; // terminate after fatal errors
                break;
            default:
                assert false :
                    Messages.format( Messages.UNRECOGNIZED_SEVERITY,
                            event.getSeverity() );
        }

        // calculate the location message
        String location = getLocation( event );

        System.out.println(
            Messages.format( Messages.SEVERITY_MESSAGE,
                             severity,
                             event.getMessage(),
                             location ) );

        // fail on the first error or fatal error
        return retVal;
    }

    /**
     * Calculate a location message for the event
     *
     */
    private String getLocation(ValidationEvent event) {
        StringBuilder msg = new StringBuilder();

        ValidationEventLocator locator = event.getLocator();

        if( locator != null ) {

            URL url = locator.getURL();
            Object obj = locator.getObject();
            Node node = locator.getNode();
            int line = locator.getLineNumber();

            if( url!=null || line!=-1 ) {
                msg.append("line ").append(line);
                if( url!=null )
                    msg.append(" of ").append(url);
            } else if( obj != null ) {
                msg.append(" obj: ").append(obj.toString());
            } else if( node != null ) {
                msg.append(" node: ").append(node.toString());
            }
        } else {
            msg.append( Messages.format( Messages.LOCATION_UNAVAILABLE ) );
        }

        return msg.toString();
    }
}