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.io.filefilter;
018    
019    import java.io.File;
020    import java.io.Serializable;
021    
022    /**
023     * This filter produces a logical NOT of the filters specified.
024     *
025     * @since Commons IO 1.0
026     * @version $Revision: 591058 $ $Date: 2007-11-01 15:47:05 +0000 (Thu, 01 Nov 2007) $
027     * 
028     * @author Stephen Colebourne
029     */
030    public class NotFileFilter extends AbstractFileFilter implements Serializable {
031        
032        /** The filter */
033        private final IOFileFilter filter;
034    
035        /**
036         * Constructs a new file filter that NOTs the result of another filters.
037         * 
038         * @param filter  the filter, must not be null
039         * @throws IllegalArgumentException if the filter is null
040         */
041        public NotFileFilter(IOFileFilter filter) {
042            if (filter == null) {
043                throw new IllegalArgumentException("The filter must not be null");
044            }
045            this.filter = filter;
046        }
047    
048        /**
049         * Checks to see if both filters are true.
050         * 
051         * @param file  the File to check
052         * @return true if the filter returns false
053         */
054        public boolean accept(File file) {
055            return ! filter.accept(file);
056        }
057        
058        /**
059         * Checks to see if both filters are true.
060         * 
061         * @param file  the File directory
062         * @param name  the filename
063         * @return true if the filter returns false
064         */
065        public boolean accept(File file, String name) {
066            return ! filter.accept(file, name);
067        }
068    
069        /**
070         * Provide a String representaion of this file filter.
071         *
072         * @return a String representaion
073         */
074        public String toString() {
075            return super.toString() + "(" + filter.toString()  + ")";
076        }
077        
078    }