    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *     http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017
    018package org.apache.commons.configuration2;
    019
    020/**
    021 * <p>
    022 * A specialized SAX2 XML parser that processes configuration objects.
    023 * </p>
    024 *
    025 * <p>
    026 * This class mimics to be a SAX compliant XML parser. It is able to iterate over the keys in a configuration object and
    027 * to generate corresponding SAX events. By registering a {@code ContentHandler} at an instance it is possible to
    028 * perform XML processing on a configuration object.
    029 * </p>
    030 */
    031public class BaseConfigurationXMLReader extends ConfigurationXMLReader {
    032    /**
    033     * An internally used helper class to iterate over all configuration keys ant to generate corresponding SAX events.
    034     */
    035    final class SAXConverter extends HierarchicalConfigurationConverter {
    036        /**
    037         * Callback for the end of an element.
    038         *
    039         * @param name the element name
    040         */
    041        @Override
    042        protected void elementEnd(final String name) {
    043            fireElementEnd(name);
    044        }
    045
    046        /**
    047         * Callback for the start of an element.
    048         *
    049         * @param name the element name
    050         * @param value the element value
    051         */
    052        @Override
    053        protected void elementStart(final String name, final Object value) {
    054            fireElementStart(name, null);
    055            if (value != null) {
    056                fireCharacters(value.toString());
    057            }
    058        }
    059    }
    060
    061    /** Stores the actual configuration. */
    062    private Configuration config;
    063
    064    /**
    065     * Creates a new instance of {@code BaseConfigurationXMLReader}.
    066     */
    067    public BaseConfigurationXMLReader() {
    068    }
    069
    070    /**
    071     * Creates a new instance of {@code BaseConfigurationXMLReader} and sets the configuration object to be parsed.
    072     *
    073     * @param conf the configuration to be parsed
    074     */
    075    public BaseConfigurationXMLReader(final Configuration conf) {
    076        this();
    077        setConfiguration(conf);
    078    }
    079
    080    /**
    081     * Gets the actual configuration to be processed.
    082     *
    083     * @return the actual configuration
    084     */
    085    public Configuration getConfiguration() {
    086        return config;
    087    }
    088
    089    /**
    090     * Gets the configuration to be processed.
    091     *
    092     * @return the actual configuration
    093     */
    094    @Override
    095    public Configuration getParsedConfiguration() {
    096        return getConfiguration();
    097    }
    098
    099    /**
    100     * The main SAX event generation method. This element uses an internal {@code HierarchicalConfigurationConverter} object
    101     * to iterate over all keys in the actual configuration and to generate corresponding SAX events.
    102     */
    103    @Override
    104    protected void processKeys() {
    105        fireElementStart(getRootName(), null);
    106        new SAXConverter().process(getConfiguration());
    107        fireElementEnd(getRootName());
    108    }
    109
    110    /**
    111     * Sets the configuration to be processed.
    112     *
    113     * @param conf the configuration
    114     */
    115    public void setConfiguration(final Configuration conf) {
    116        config = conf;
    117    }
    118}