net.darkmist.clf.DirTraverser.java Source code

Introduction

Here is the source code for net.darkmist.clf.DirTraverser.java

Source

/*
 *  Copyright (C) 2012 Ed Schaller <schallee@darkmist.net>
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package net.darkmist.clf;

import java.io.File;
import java.util.Arrays;
import java.util.NoSuchElementException;
import java.util.Queue;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class DirTraverser {
    private static final Class<DirTraverser> CLASS = DirTraverser.class;
    @SuppressWarnings("unused")
    private static final String CLASS_NAME = CLASS.getName();
    @SuppressWarnings("unused")
    private static final Log logger = LogFactory.getLog(CLASS);

    private FileHandler fileHandler;
    private Queue<File> frontier;

    public DirTraverser(Queue<File> frontier, FileHandler fileHandler) {
        if (frontier == null)
            frontier = Util.newQueue();
        this.frontier = frontier;
        this.fileHandler = fileHandler;
    }

    public DirTraverser(File start, FileHandler fileHandler) {
        this(Util.newQueue(start), fileHandler);
    }

    private void onFile(File file) {
        if (file.isDirectory())
            frontier.offer(file);
        else if (fileHandler != null)
            fileHandler.handleFile(file);
    }

    private static <T> T[] sort(T... a) {
        Arrays.sort(a);
        return a;
    }

    public void run() {
        File dir;

        try {
            while ((dir = frontier.remove()) != null) {
                for (File file : sort(dir.listFiles()))
                    onFile(file);
            }
        } catch (NoSuchElementException ignored) {
            // we're done
        }
    }
}