/*
* 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:[email protected]">Ricardo Gladwell</a>
* @version $Revision: 492216 $, $Date: 2007-01-03 17:51:24 +0100 (Mi, 03. Jan 2007) $
* @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;
}
/**
* Returns a set with the entries contained in this configuration-based map.
*
* @return a set with the contained entries
* @see java.util.Map#entrySet()
*/
public Set entrySet()
{
return new ConfigurationSet(configuration);
}
/**
* Stores the value for the specified key. The value is stored in the
* underlying configuration.
*
* @param key the key (will be converted to a string)
* @param value the value
* @return the old value of this key or <b>null</b> if it is new
* @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;
}
/**
* Returns the value of the specified key. The key is converted to a string
* and then passed to the underlying configuration.
*
* @param key the key
* @return the value of this key
* @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();
}
}
}
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