Java Folder Read by Extension getFilesWithinPath(File path, String fileExtension)

Description

Returns all the files within the parent directory (including sub-dirs) that have the supplied extension.

License

Open Source License

Declaration

public static List<File> getFilesWithinPath(File path, String fileExtension) 

Method Source Code

//package com.java2s;
/*/*from   w  w  w.  ja v  a2  s .  c  o  m*/
 * Robonobo Common Utils
 * Copyright (C) 2008 Will Morton (macavity@well.com) & Ray Hilton (ray@wirestorm.net)
    
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
    
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
    
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

import java.io.*;
import java.util.ArrayList;
import java.util.List;

public class Main {
    /**
     * Returns all the files within the parent directory (including sub-dirs)
     * that have the supplied extension. If extension is null, will return all
     * files. Will not return the sub-dirs themselves.
     * 
     * If the path is a file, it will be returned in the list it matches, or else an empty list will be returned
     */
    public static List<File> getFilesWithinPath(File path, String fileExtension) {
        List<File> result = new ArrayList<File>();
        if (!path.isDirectory()) {
            if (fileExtension == null || fileExtension.equalsIgnoreCase(getFileExtension(path)))
                result.add(path);
            return result;
        }
        addChildFilesToList(path, result, fileExtension);
        return result;
    }

    /**
     * Returns the file extension, without the initial period. If there is no
     * period in the file name, returns an empty string.
     */
    public static String getFileExtension(File f) {
        String fileName = f.getName();
        if (fileName.contains("."))
            return fileName.substring(fileName.lastIndexOf(".") + 1);
        else
            return "";
    }

    private static void addChildFilesToList(File directory, List<File> list, String fileExtension) {
        for (File f : directory.listFiles()) {
            if (f.isDirectory())
                addChildFilesToList(f, list, fileExtension);
            else if (fileExtension == null || fileExtension.equalsIgnoreCase(getFileExtension(f)))
                list.add(f);
        }
    }
}

Related

1. getFilesForType(final File target, final String extension)
2. getFilesFromExtension(String directory, String[] extensions)
3. getFilesWithExtension(File aDirectory, final String aExtension)
4. getFilesWithExtension(File dir, String extension)
5. getFilesWithExtension(String directory, String extension)