/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.xerces.util;

import org.apache.xerces.xni.parser.XMLErrorHandler;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;

Wraps XMLErrorHandler and make it look like a SAX ErrorHandler. 
 The derived class should override the getErrorHandler() method so that it will return the correct XMLErrorHandler instance. This method will be called whenever an error/warning is found. 
 Experience shows that it is better to store the actual XMLErrorHandler in one place and looks up that variable, rather than copying it into every component that needs an error handler and update all of them whenever it is changed, IMO. 
Author:
Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)
Version:
$Id: ErrorHandlerProxy.java 447241 2006-09-18 05:12:57Z mrglavas $/**
 * Wraps {@link XMLErrorHandler} and make it look like a SAX {@link ErrorHandler}.  
 * 
 * <p>
 * The derived class should override the {@link #getErrorHandler()} method
 * so that it will return the correct {@link XMLErrorHandler} instance.
 * This method will be called whenever an error/warning is found.
 * 
 * <p>
 * Experience shows that it is better to store the actual
 * {@link XMLErrorHandler} in one place and looks up that variable,
 * rather than copying it into every component that needs an error handler
 * and update all of them whenever it is changed, IMO.
 * 
 * @author Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)
 * 
 * @version $Id: ErrorHandlerProxy.java 447241 2006-09-18 05:12:57Z mrglavas $
 */
public abstract class ErrorHandlerProxy implements ErrorHandler {
    
    public void error(SAXParseException e) throws SAXException {
        XMLErrorHandler eh = getErrorHandler();
        if (eh instanceof ErrorHandlerWrapper) {
            ((ErrorHandlerWrapper)eh).fErrorHandler.error(e);
        }
        else {
            eh.error("","",ErrorHandlerWrapper.createXMLParseException(e));
        }
        // if an XNIException is thrown, just let it go.
        // REVISIT: is this OK? or should we try to wrap it into SAXException?
    }

    public void fatalError(SAXParseException e) throws SAXException {
        XMLErrorHandler eh = getErrorHandler();
        if (eh instanceof ErrorHandlerWrapper) {
            ((ErrorHandlerWrapper)eh).fErrorHandler.fatalError(e);
        }
        else {
            eh.fatalError("","",ErrorHandlerWrapper.createXMLParseException(e));
        }
    }

    public void warning(SAXParseException e) throws SAXException {
        XMLErrorHandler eh = getErrorHandler();
        if (eh instanceof ErrorHandlerWrapper) {
            ((ErrorHandlerWrapper)eh).fErrorHandler.warning(e);
        }
        else {
            eh.warning("","",ErrorHandlerWrapper.createXMLParseException(e));
        }
    }

    protected abstract XMLErrorHandler getErrorHandler();
}