core/src/test/java/org/apache/commons/digester3/annotations/catalog/BookFactory.java

/* $Id$
 *
 * 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.commons.digester3.annotations.catalog;

import org.apache.commons.digester3.AbstractObjectCreationFactory;
import org.xml.sax.Attributes;

/**
 * @since 2.1
 */
public final class BookFactory
    extends AbstractObjectCreationFactory<Book>
{

    private final static String ISBN = "isbn";

    @Override
    public Book createObject( Attributes attributes )
        throws Exception
    {
        String isbn = attributes.getValue( ISBN );

        if ( isbn == null )
        {
            throw new Exception( "Mandatory isbn attribute not present on book tag." );
        }

        return new Book( isbn );
    }

}