1/*
2 *  Licensed to the Apache Software Foundation (ASF) under one or more
3 *  contributor license agreements.  See the NOTICE file distributed with
4 *  this work for additional information regarding copyright ownership.
5 *  The ASF licenses this file to You under the Apache License, Version 2.0
6 *  (the "License"); you may not use this file except in compliance with
7 *  the License.  You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 *  Unless required by applicable law or agreed to in writing, software
12 *  distributed under the License is distributed on an "AS IS" BASIS,
13 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 *  See the License for the specific language governing permissions and
15 *  limitations under the License.
16 */
17
18package org.apache.harmony.luni.util;
19
20public final class URLUtil {
21
22    /**
23     * Canonicalize the path, i.e. remove ".." and "." occurences.
24     *
25     * @param path the path to be canonicalized
26     * @return the canonicalized path
27     */
28    public static String canonicalizePath(String path) {
29        int dirIndex;
30
31        while ((dirIndex = path.indexOf("/./")) >= 0) { //$NON-NLS-1$
32            path = path.substring(0, dirIndex + 1)
33                    + path.substring(dirIndex + 3);
34        }
35
36        if (path.endsWith("/.")) { //$NON-NLS-1$
37            path = path.substring(0, path.length() - 1);
38        }
39
40        while ((dirIndex = path.indexOf("/../")) >= 0) { //$NON-NLS-1$
41            if (dirIndex != 0) {
42                path = path.substring(0, path
43                        .lastIndexOf('/', dirIndex - 1))
44                        + path.substring(dirIndex + 3);
45            } else {
46                path = path.substring(dirIndex + 3);
47            }
48        }
49
50        if (path.endsWith("/..") && path.length() > 3) { //$NON-NLS-1$
51            path = path.substring(0, path.lastIndexOf('/',
52                    path.length() - 4) + 1);
53        }
54        return path;
55    }
56}
57