001/*
002 * (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Nuxeo - initial API and implementation
018 *
019 * $Id$
020 */
021
022package org.nuxeo.osgi.application;
023
024import java.io.File;
025
026/**
027 * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a>
028 */
029public class FileWalker {
030
031    public static final int CONTINUE = 0;
032
033    public static final int RETURN = 1;
034
035    public static final int BREAK = 2;
036
037    public static int walk(File root, Visitor visitor) {
038        int ret = 0; // -1 stop walking, 0 continue, 1 break walking
039        for (File file : root.listFiles()) {
040            if (file.isDirectory()) {
041                ret = visitor.visitDirectory(file);
042                if (ret == RETURN) {
043                    return RETURN;
044                } else if (ret == BREAK) {
045                    return CONTINUE;
046                } else { // go down in the tree
047                    ret = walk(file, visitor);
048                    if (ret == RETURN) {
049                        return RETURN;
050                    }
051                }
052            } else {
053                ret = visitor.visitFile(file);
054                if (ret == RETURN) {
055                    return RETURN;
056                } else if (ret == BREAK) {
057                    return CONTINUE;
058                }
059            }
060        }
061        return CONTINUE;
062    }
063
064    public abstract static class Visitor {
065        public int visitFile(File file) {
066            // do something here
067            return CONTINUE;
068        }
069
070        public int visitDirectory(File file) {
071            // do something here
072            return CONTINUE;
073        }
074    }
075
076}