001    /*
002     *  Licensed to the Apache Software Foundation (ASF) under one or more
003     *  contributor license agreements.  See the NOTICE file distributed with
004     *  this work for additional information regarding copyright ownership.
005     *  The ASF licenses this file to You under the Apache License, Version 2.0
006     *  (the "License"); you may not use this file except in compliance with
007     *  the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     *  Unless required by applicable law or agreed to in writing, software
012     *  distributed under the License is distributed on an "AS IS" BASIS,
013     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     *  See the License for the specific language governing permissions and
015     *  limitations under the License.
016     */
017    package org.apache.commons.collections.set;
018    
019    import java.util.Set;
020    
021    import org.apache.commons.collections.Transformer;
022    import org.apache.commons.collections.collection.TransformedCollection;
023    
024    /**
025     * Decorates another <code>Set</code> to transform objects that are added.
026     * <p>
027     * The add methods are affected by this class.
028     * Thus objects must be removed or searched for using their transformed form.
029     * For example, if the transformation converts Strings to Integers, you must
030     * use the Integer form to remove objects.
031     * <p>
032     * This class is Serializable from Commons Collections 3.1.
033     * 
034     * @since Commons Collections 3.0
035     * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
036     * 
037     * @author Stephen Colebourne
038     */
039    public class TransformedSet extends TransformedCollection implements Set {
040    
041        /** Serialization version */
042        private static final long serialVersionUID = 306127383500410386L;
043    
044        /**
045         * Factory method to create a transforming set.
046         * <p>
047         * If there are any elements already in the set being decorated, they
048         * are NOT transformed.
049         * 
050         * @param set  the set to decorate, must not be null
051         * @param transformer  the transformer to use for conversion, must not be null
052         * @throws IllegalArgumentException if set or transformer is null
053         */
054        public static Set decorate(Set set, Transformer transformer) {
055            return new TransformedSet(set, transformer);
056        }
057        
058        //-----------------------------------------------------------------------
059        /**
060         * Constructor that wraps (not copies).
061         * <p>
062         * If there are any elements already in the set being decorated, they
063         * are NOT transformed.
064         * 
065         * @param set  the set to decorate, must not be null
066         * @param transformer  the transformer to use for conversion, must not be null
067         * @throws IllegalArgumentException if set or transformer is null
068         */
069        protected TransformedSet(Set set, Transformer transformer) {
070            super(set, transformer);
071        }
072    
073    }