/*

  * 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.configuration;

 import java.util.ArrayList;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Map;

 import java.util.Properties;

 import org.apache.commons.collections.ExtendedProperties;

 import org.apache.commons.lang.StringUtils;

 /**

  * Configuration converter. Helper class to convert between Configuration,

  * ExtendedProperties and standard Properties.

  *

  * @author <a href="mailto:mpoeschl@marmot.at">Martin Poeschl</a>

  * @version $Id: ConfigurationConverter.java 1208788 2011-11-30 21:15:37Z oheger $

  */

 public final class ConfigurationConverter

 {

     /**

      * Private constructor prevents instances from being created.

      */

     private ConfigurationConverter()

     {

         // to prevent instanciation...

     }

     /**

      * Convert a ExtendedProperties class into a Configuration class.

      *

      * @param eprops ExtendedProperties object to convert

      * @return Configuration created from the ExtendedProperties

      */

     public static Configuration getConfiguration(ExtendedProperties eprops)

     {

         return new MapConfiguration(eprops);

     }

     /**

      * Convert a standard Properties class into a configuration class.

      *

      * @param props properties object to convert

      * @return Configuration configuration created from the Properties

      */

     public static Configuration getConfiguration(Properties props)

     {

         return new MapConfiguration(props);

     }

     /**

      * Convert a Configuration class into a ExtendedProperties class.

      *

      * @param config Configuration object to convert

      * @return ExtendedProperties created from the Configuration

      */

     public static ExtendedProperties getExtendedProperties(Configuration config)

     {

         ExtendedProperties props = new ExtendedProperties();

         for (Iterator<String> keys = config.getKeys(); keys.hasNext();)

         {

             String key = keys.next();

             Object property = config.getProperty(key);

             // turn lists into vectors

             if (property instanceof List)

             {

                 property = new ArrayList<Object>((List<?>) property);

             }

             props.setProperty(key, property);

         }

         return props;

     }

     /**

      * Convert a Configuration class into a Properties class. List properties

      * are joined into a string using the delimiter of the configuration if it

      * extends AbstractConfiguration, and a comma otherwise.

      *

      * @param config Configuration object to convert

      * @return Properties created from the Configuration

      */

     public static Properties getProperties(Configuration config)

     {

         Properties props = new Properties();

         char delimiter = (config instanceof AbstractConfiguration)

             ? ((AbstractConfiguration) config).getListDelimiter() : ',';

         for (Iterator<String> keys = config.getKeys(); keys.hasNext();)

         {

             String key = keys.next();

             List<Object> list = config.getList(key);

             // turn the list into a string

             props.setProperty(key, StringUtils.join(list.iterator(), delimiter));

         }

         return props;

     }

     /**

      * Convert a Configuration class into a Map class.

      *

      * @param config Configuration object to convert

      * @return Map created from the Configuration

      */

     public static Map<Object, Object> getMap(Configuration config)

     {

         return new ConfigurationMap(config);

     }

 }