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}