/*
 * 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.web;

import java.util.List;

import org.apache.commons.configuration.AbstractConfiguration;
import org.apache.commons.configuration.PropertyConverter;


An abstract base class for all web configurations.

 This class implements common functionality used by all web based configurations. E.g. some methods are not supported by configurations of this type, so they throw a UnsupportedOperationException exception. 
Author:
Commons
Configuration team
Version:
$Id: BaseWebConfiguration.java 1211122 2011-12-06 20:55:45Z oheger $
Since:
1.2/**
 * <p>
 * An abstract base class for all web configurations.
 * </p>
 * <p>
 * This class implements common functionality used by all web based
 * configurations. E.g. some methods are not supported by configurations of this
 * type, so they throw a {@code UnsupportedOperationException} exception.
 * </p>
 *
 * @author <a
 * href="http://commons.apache.org/configuration/team-list.html">Commons
 * Configuration team</a>
 * @version $Id: BaseWebConfiguration.java 1211122 2011-12-06 20:55:45Z oheger $
 * @since 1.2
 */
abstract class BaseWebConfiguration extends AbstractConfiguration
{
    
Checks if this configuration is empty. This implementation makes use of the getKeys() method (which must be defined by concrete sub classes) to find out whether properties exist. 
Returns:
a flag whether this configuration is empty/**
     * Checks if this configuration is empty. This implementation makes use of
     * the {@code getKeys()} method (which must be defined by concrete
     * sub classes) to find out whether properties exist.
     *
     * @return a flag whether this configuration is empty
     */
    public boolean isEmpty()
    {
        return !getKeys().hasNext();
    }

    
Checks whether the specified key is stored in this configuration.
Params:
key – the key
Returns:
a flag whether this key exists in this configuration/**
     * Checks whether the specified key is stored in this configuration.
     *
     * @param key the key
     * @return a flag whether this key exists in this configuration
     */
    public boolean containsKey(String key)
    {
        return getProperty(key) != null;
    }

    
Removes the property with the given key. This operation is not
supported and will throw an UnsupportedOperationException.
Params:
key – the key of the property to be removed
Throws:
UnsupportedOperationException – because this operation is not
allowed/**
     * Removes the property with the given key. <strong>This operation is not
     * supported and will throw an UnsupportedOperationException.</strong>
     *
     * @param key the key of the property to be removed
     * @throws UnsupportedOperationException because this operation is not
     * allowed
     */
    @Override
    public void clearProperty(String key)
    {
        throw new UnsupportedOperationException("Read only configuration");
    }

    
Adds a property to this configuration. This operation is not
supported and will throw an UnsupportedOperationException.
Params:
key – the key of the property
obj – the value to be added
Throws:
UnsupportedOperationException – because this operation is not
allowed/**
     * Adds a property to this configuration. <strong>This operation is not
     * supported and will throw an UnsupportedOperationException.</strong>
     *
     * @param key the key of the property
     * @param obj the value to be added
     * @throws UnsupportedOperationException because this operation is not
     * allowed
     */
    @Override
    protected void addPropertyDirect(String key, Object obj)
    {
        throw new UnsupportedOperationException("Read only configuration");
    }

    
Takes care of list delimiters in property values. This method checks if
delimiter parsing is enabled and the passed in value contains a delimiter
character. If this is the case, a split operation is performed.
Params:
value – the property value to be examined
Returns:
the processed value/**
     * Takes care of list delimiters in property values. This method checks if
     * delimiter parsing is enabled and the passed in value contains a delimiter
     * character. If this is the case, a split operation is performed.
     *
     * @param value the property value to be examined
     * @return the processed value
     */
    protected Object handleDelimiters(Object value)
    {
        if (!isDelimiterParsingDisabled() && value instanceof String)
        {
            List<String> list = PropertyConverter.split((String) value,
                    getListDelimiter());
            value = list.size() > 1 ? list : list.get(0);
        }

        return value;
    }
}