/*
* 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;
/**
* <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</code> exception.
* </p>
*
* @author Oliver Heger
* @version $Id: BaseWebConfiguration.java 515306 2007-03-06 21:15:00Z oheger $
* @since 1.2
*/
abstract class BaseWebConfiguration extends AbstractConfiguration
{
/**
* Checks if this configuration is empty. This implementation makes use of
* the <code>getKeys()</code> 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.
*
* @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. <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
*/
public void clearProperty(String key)
{
throw new UnsupportedOperationException("Read only configuration");
}
/**
* 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
*/
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.
*
* @param value the property value to be examined
* @return the processed value
*/
protected Object handleDelimiters(Object value)
{
if (!isDelimiterParsingDisabled() && value instanceof String)
{
List list = PropertyConverter.split((String) value,
getListDelimiter());
value = list.size() > 1 ? list : list.get(0);
}
return value;
}
}
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