view src/org/tmatesoft/hg/util/FileWalker.java @ 158:b413b16d10a5

Integer offsets and file length explictly, rather than casts throughout code. Inflater may benefit from total length hint, but shall calculate it by its own if needed
author Artem Tikhomirov <tikhomirov.artem@gmail.com>
date Wed, 09 Mar 2011 13:16:37 +0100
parents 8248aae33f7d
children 26ad7827a62d
line wrap: on
line source
/*
 * Copyright (c) 2011 TMate Software Ltd
 *  
 * 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; version 2 of the License.
 *
 * 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.
 *
 * For information on how to redistribute this software under
 * the terms of a license other than GNU General Public License
 * contact TMate Software at support@hg4j.com
 */
package org.tmatesoft.hg.util;

import java.io.File;
import java.util.LinkedList;
import java.util.NoSuchElementException;

/**
 * 
 * @author Artem Tikhomirov
 * @author TMate Software Ltd.
 */
public class FileWalker implements FileIterator {

	private final File startDir;
	private final Path.Source pathHelper;
	private final LinkedList<File> dirQueue;
	private final LinkedList<File> fileQueue;
	private File nextFile;
	private Path nextPath;

	public FileWalker(File dir, Path.Source pathFactory) {
		startDir = dir;
		pathHelper = pathFactory;
		dirQueue = new LinkedList<File>();
		fileQueue = new LinkedList<File>();
		reset();
	}

	public void reset() {
		fileQueue.clear();
		dirQueue.clear();
		dirQueue.add(startDir);
		nextFile = null;
		nextPath = null;
	}
	
	public boolean hasNext() {
		return fill();
	}

	public void next() {
		if (!fill()) {
			throw new NoSuchElementException();
		}
		nextFile = fileQueue.removeFirst();
		nextPath = pathHelper.path(nextFile.getPath());
	}

	public Path name() {
		return nextPath;
	}
	
	public File file() {
		return nextFile;
	}
	
	private File[] listFiles(File f) {
		// in case we need to solve os-related file issues (mac with some encodings?)
		return f.listFiles();
	}

	// return true when fill added any elements to fileQueue. 
	private boolean fill() {
		while (fileQueue.isEmpty()) {
			if (dirQueue.isEmpty()) {
				return false;
			}
			while (!dirQueue.isEmpty()) {
				File dir = dirQueue.removeFirst();
				for (File f : listFiles(dir)) {
					if (f.isDirectory()) {
						if (!".hg".equals(f.getName())) {
							dirQueue.addLast(f);
						}
					} else {
						fileQueue.addLast(f);
					}
				}
				break;
			}
		}
		return !fileQueue.isEmpty();
	}
}