    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 */
    017package org.apache.commons.io.filefilter;
    018
    019import java.io.File;
    020import java.io.Serializable;
    021import java.util.Date;
    022
    023import org.apache.commons.io.FileUtils;
    024
    025/**
    026 * Filters files based on a cutoff time, can filter either newer
    027 * files or files equal to or older.
    028 * <p>
    029 * For example, to print all files and directories in the
    030 * current directory older than one day:
    031 *
    032 * <pre>
    033 * File dir = new File(".");
    034 * // We are interested in files older than one day
    035 * long cutoff = System.currentTimeMillis() - (24 * 60 * 60 * 1000);
    036 * String[] files = dir.list( new AgeFileFilter(cutoff) );
    037 * for ( int i = 0; i &lt; files.length; i++ ) {
    038 *     System.out.println(files[i]);
    039 * }
    040 * </pre>
    041 *
    042 * @see FileFilterUtils#ageFileFilter(Date)
    043 * @see FileFilterUtils#ageFileFilter(File)
    044 * @see FileFilterUtils#ageFileFilter(long)
    045 * @see FileFilterUtils#ageFileFilter(Date, boolean)
    046 * @see FileFilterUtils#ageFileFilter(File, boolean)
    047 * @see FileFilterUtils#ageFileFilter(long, boolean)
    048 * @since 1.2
    049 */
    050public class AgeFileFilter extends AbstractFileFilter implements Serializable {
    051
    052    private static final long serialVersionUID = -2132740084016138541L;
    053
    054    /** The cutoff time threshold. */
    055    private final long cutoff;
    056    /** Whether the files accepted will be older or newer. */
    057    private final boolean acceptOlder;
    058
    059    /**
    060     * Constructs a new age file filter for files equal to or older than
    061     * a certain cutoff
    062     *
    063     * @param cutoff  the threshold age of the files
    064     */
    065    public AgeFileFilter(final long cutoff) {
    066        this(cutoff, true);
    067    }
    068
    069    /**
    070     * Constructs a new age file filter for files on any one side
    071     * of a certain cutoff.
    072     *
    073     * @param cutoff  the threshold age of the files
    074     * @param acceptOlder  if true, older files (at or before the cutoff)
    075     * are accepted, else newer ones (after the cutoff).
    076     */
    077    public AgeFileFilter(final long cutoff, final boolean acceptOlder) {
    078        this.acceptOlder = acceptOlder;
    079        this.cutoff = cutoff;
    080    }
    081
    082    /**
    083     * Constructs a new age file filter for files older than (at or before)
    084     * a certain cutoff date.
    085     *
    086     * @param cutoffDate  the threshold age of the files
    087     */
    088    public AgeFileFilter(final Date cutoffDate) {
    089        this(cutoffDate, true);
    090    }
    091
    092    /**
    093     * Constructs a new age file filter for files on any one side
    094     * of a certain cutoff date.
    095     *
    096     * @param cutoffDate  the threshold age of the files
    097     * @param acceptOlder  if true, older files (at or before the cutoff)
    098     * are accepted, else newer ones (after the cutoff).
    099     */
    100    public AgeFileFilter(final Date cutoffDate, final boolean acceptOlder) {
    101        this(cutoffDate.getTime(), acceptOlder);
    102    }
    103
    104    /**
    105     * Constructs a new age file filter for files older than (at or before)
    106     * a certain File (whose last modification time will be used as reference).
    107     *
    108     * @param cutoffReference  the file whose last modification
    109     *        time is used as the threshold age of the files
    110     */
    111    public AgeFileFilter(final File cutoffReference) {
    112        this(cutoffReference, true);
    113    }
    114
    115    /**
    116     * Constructs a new age file filter for files on any one side
    117     * of a certain File (whose last modification time will be used as
    118     * reference).
    119     *
    120     * @param cutoffReference  the file whose last modification
    121     *        time is used as the threshold age of the files
    122     * @param acceptOlder  if true, older files (at or before the cutoff)
    123     * are accepted, else newer ones (after the cutoff).
    124     */
    125    public AgeFileFilter(final File cutoffReference, final boolean acceptOlder) {
    126        this(cutoffReference.lastModified(), acceptOlder);
    127    }
    128
    129    //-----------------------------------------------------------------------
    130    /**
    131     * Checks to see if the last modification of the file matches cutoff
    132     * favorably.
    133     * <p>
    134     * If last modification time equals cutoff and newer files are required,
    135     * file <b>IS NOT</b> selected.
    136     * If last modification time equals cutoff and older files are required,
    137     * file <b>IS</b> selected.
    138     *
    139     * @param file  the File to check
    140     * @return true if the file name matches
    141     */
    142    @Override
    143    public boolean accept(final File file) {
    144        final boolean newer = FileUtils.isFileNewer(file, cutoff);
    145        return acceptOlder != newer;
    146    }
    147
    148    /**
    149     * Provide a String representation of this file filter.
    150     *
    151     * @return a String representation
    152     */
    153    @Override
    154    public String toString() {
    155        final String condition = acceptOlder ? "<=" : ">";
    156        return super.toString() + "(" + condition + cutoff + ")";
    157    }
    158}