/*
* 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.collections;
/**
* Marker interface for collections, maps and iterators that are unmodifiable.
* <p>
* This interface enables testing such as:
* <pre>
* if (coll instanceof Unmodifiable) {
* coll = new ArrayList(coll);
* }
* // now we know coll is modifiable
* </pre>
* Of course all this only works if you use the Unmodifiable classes defined
* in this library. If you use the JDK unmodifiable class via java util Collections
* then the interface won't be there.
*
* @since Commons Collections 3.0
* @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
*
* @author Stephen Colebourne
*/
public interface Unmodifiable {
// marker interface - no methods to implement
}