/*

  * 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.AbstractMap;

 import java.util.AbstractSet;

 import java.util.Iterator;

 import java.util.Map;

 import java.util.Set;

 /**

  * <p>The <code>ConfigurationMap</code> wraps a

  * configuration-collection

  * {@link org.apache.commons.configuration.Configuration}

  * instance to provide a <code>Map</code> interface.</p>

  *

  * <p><em>Note:</em> This implementation is incomplete.</p>

  *

  * @author <a href="mailto:ricardo.gladwell@btinternet.com">Ricardo Gladwell</a>

  * @version $Revision: 439648 $, $Date: 2006-09-02 22:42:10 +0200 (Sa, 02 Sep 2006) $

  * @since 1.0

  */

 public class ConfigurationMap extends AbstractMap

 {

     /**

      * The <code>Configuration</code> wrapped by this class.

      */

     private Configuration configuration;

     /**

      * Creates a new instance of a <code>ConfigurationMap</code>

      * that wraps the specified <code>Configuration</code>

      * instance.

      * @param configuration <code>Configuration</code>

      * instance.

      */

     public ConfigurationMap(Configuration configuration)

     {

         this.configuration = configuration;

     }

     /**

      * Returns the wrapped <code>Configuration</code> object.

      *

      * @return the wrapped configuration

      * @since 1.2

      */

     public Configuration getConfiguration()

     {

         return configuration;

     }

     /**

      * @see java.util.Map#entrySet()

      */

     public Set entrySet()

     {

         return new ConfigurationSet(configuration);

     }

     /**

      * @see java.util.Map#put(java.lang.Object, java.lang.Object)

      */

     public Object put(Object key, Object value)

     {

         String strKey = String.valueOf(key);

         Object old = configuration.getProperty(strKey);

         configuration.setProperty(strKey, value);

         return old;

     }

     /**

      * @see java.util.Map#get(java.lang.Object)

      */

     public Object get(Object key)

     {

         return configuration.getProperty(String.valueOf(key));

     }

     /**

      * Set of entries in the map.

      */

     static class ConfigurationSet extends AbstractSet

     {

         /** The configuration mapped to this entry set. */

         private Configuration configuration;

         /**

          * A Map entry in the ConfigurationMap.

          */

         private final class Entry implements Map.Entry

         {

             /** The key of the map entry. */

             private Object key;

             private Entry(Object key)

             {

                 this.key = key;

             }

             public Object getKey()

             {

                 return key;

             }

             public Object getValue()

             {

                 return configuration.getProperty((String) key);

             }

             public Object setValue(Object value)

             {

                 Object old = getValue();

                 configuration.setProperty((String) key, value);

                 return old;

             }

         }

         /**

          * Iterator over the entries in the ConfigurationMap.

          */

         private final class ConfigurationSetIterator implements Iterator

         {

             /** An iterator over the keys in the configuration. */

             private Iterator keys;

             private ConfigurationSetIterator()

             {

                 keys = configuration.getKeys();

             }

             public boolean hasNext()

             {

                 return keys.hasNext();

             }

             public Object next()

             {

                 return new Entry(keys.next());

             }

             public void remove()

             {

                 keys.remove();

             }

         }

         ConfigurationSet(Configuration configuration)

         {

             this.configuration = configuration;

         }

         /**

          * @see java.util.Collection#size()

          */

         public int size()

         {

             // Ouch. Now _that_ one is expensive...

             int count = 0;

             for (Iterator iterator = configuration.getKeys(); iterator.hasNext();)

             {

                 iterator.next();

                 count++;

             }

             return count;

         }

         /**

          * @see java.util.Collection#iterator()

          */

         public Iterator iterator()

         {

             return new ConfigurationSetIterator();

         }

     }

 }