    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: 1005099 $ $Date: 2010-10-06 17:13:01 +0100 (Wed, 06 Oct 2010) $
    027     *
    028     * @author Stephen Colebourne
    029     * @see FileFilterUtils#notFileFilter(IOFileFilter)
    030     */
    031    public class NotFileFilter extends AbstractFileFilter implements Serializable {
    032
    033        /** The filter */
    034        private final IOFileFilter filter;
    035
    036        /**
    037         * Constructs a new file filter that NOTs the result of another filter.
    038         *
    039         * @param filter  the filter, must not be null
    040         * @throws IllegalArgumentException if the filter is null
    041         */
    042        public NotFileFilter(IOFileFilter filter) {
    043            if (filter == null) {
    044                throw new IllegalArgumentException("The filter must not be null");
    045            }
    046            this.filter = filter;
    047        }
    048
    049        /**
    050         * Returns the logical NOT of the underlying filter's return value for the same File.
    051         *
    052         * @param file  the File to check
    053         * @return true if the filter returns false
    054         */
    055        @Override
    056        public boolean accept(File file) {
    057            return ! filter.accept(file);
    058        }
    059
    060        /**
    061         * Returns the logical NOT of the underlying filter's return value for the same arguments.
    062         *
    063         * @param file  the File directory
    064         * @param name  the filename
    065         * @return true if the filter returns false
    066         */
    067        @Override
    068        public boolean accept(File file, String name) {
    069            return ! filter.accept(file, name);
    070        }
    071
    072        /**
    073         * Provide a String representaion of this file filter.
    074         *
    075         * @return a String representaion
    076         */
    077        @Override
    078        public String toString() {
    079            return super.toString() + "(" + filter.toString()  + ")";
    080        }
    081
    082    }