Commons IO example source code file (AgeFileFilter.java)

This example Commons IO source code file (AgeFileFilter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons IO tags/keywords

abstractfilefilter, abstractfilefilter, agefilefilter, agefilefilter, io, override, override, serializable, string, string, util

The Commons IO AgeFileFilter.java source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.io.filefilter;

import java.io.File;
import java.io.Serializable;
import java.util.Date;

import org.apache.commons.io.FileUtils;

/**
 * Filters files based on a cutoff time, can filter either newer
 * files or files equal to or older.
 * <p>
 * For example, to print all files and directories in the
 * current directory older than one day:
 *
 * <pre>
 * File dir = new File(".");
 * // We are interested in files older than one day
 * long cutoff = System.currentTimeMillis() - (24 * 60 * 60 * 1000);
 * String[] files = dir.list( new AgeFileFilter(cutoff) );
 * for ( int i = 0; i < files.length; i++ ) {
 *     System.out.println(files[i]);
 * }
 * </pre>
 *
 * @author Rahul Akolkar
 * @version $Id: AgeFileFilter.java 1005099 2010-10-06 16:13:01Z niallp $
 * @see FileFilterUtils#ageFileFilter(Date)
 * @see FileFilterUtils#ageFileFilter(File)
 * @see FileFilterUtils#ageFileFilter(long)
 * @see FileFilterUtils#ageFileFilter(Date, boolean)
 * @see FileFilterUtils#ageFileFilter(File, boolean)
 * @see FileFilterUtils#ageFileFilter(long, boolean)
 * @since Commons IO 1.2
 */
public class AgeFileFilter extends AbstractFileFilter implements Serializable {

    /** The cutoff time threshold. */
    private final long cutoff;
    /** Whether the files accepted will be older or newer. */
    private final boolean acceptOlder;

    /**
     * Constructs a new age file filter for files equal to or older than
     * a certain cutoff
     *
     * @param cutoff  the threshold age of the files
     */
    public AgeFileFilter(long cutoff) {
        this(cutoff, true);
    }

    /**
     * Constructs a new age file filter for files on any one side
     * of a certain cutoff.
     *
     * @param cutoff  the threshold age of the files
     * @param acceptOlder  if true, older files (at or before the cutoff)
     * are accepted, else newer ones (after the cutoff).
     */
    public AgeFileFilter(long cutoff, boolean acceptOlder) {
        this.acceptOlder = acceptOlder;
        this.cutoff = cutoff;
    }

    /**
     * Constructs a new age file filter for files older than (at or before)
     * a certain cutoff date.
     *
     * @param cutoffDate  the threshold age of the files
     */
    public AgeFileFilter(Date cutoffDate) {
        this(cutoffDate, true);
    }

    /**
     * Constructs a new age file filter for files on any one side
     * of a certain cutoff date.
     *
     * @param cutoffDate  the threshold age of the files
     * @param acceptOlder  if true, older files (at or before the cutoff)
     * are accepted, else newer ones (after the cutoff).
     */
    public AgeFileFilter(Date cutoffDate, boolean acceptOlder) {
        this(cutoffDate.getTime(), acceptOlder);
    }

    /**
     * Constructs a new age file filter for files older than (at or before)
     * a certain File (whose last modification time will be used as reference).
     *
     * @param cutoffReference  the file whose last modification
     *        time is usesd as the threshold age of the files
     */
    public AgeFileFilter(File cutoffReference) {
        this(cutoffReference, true);
    }

    /**
     * Constructs a new age file filter for files on any one side
     * of a certain File (whose last modification time will be used as
     * reference).
     *
     * @param cutoffReference  the file whose last modification
     *        time is usesd as the threshold age of the files
     * @param acceptOlder  if true, older files (at or before the cutoff)
     * are accepted, else newer ones (after the cutoff).
     */
    public AgeFileFilter(File cutoffReference, boolean acceptOlder) {
        this(cutoffReference.lastModified(), acceptOlder);
    }

    //-----------------------------------------------------------------------
    /**
     * Checks to see if the last modification of the file matches cutoff
     * favorably.
     * <p>
     * If last modification time equals cutoff and newer files are required,
     * file <b>IS NOT selected.
     * If last modification time equals cutoff and older files are required,
     * file <b>IS selected.
     *
     * @param file  the File to check
     * @return true if the filename matches
     */
    @Override
    public boolean accept(File file) {
        boolean newer = FileUtils.isFileNewer(file, cutoff);
        return acceptOlder ? !newer : newer;
    }

    /**
     * Provide a String representaion of this file filter.
     *
     * @return a String representaion
     */
    @Override
    public String toString() {
        String condition = acceptOlder ? "<=" : ">";
        return super.toString() + "(" + condition + cutoff + ")";
    }
}