1/*
2 * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24/*
25 * @test
26 * @summary Unit test for Files.walkFileTree to test SKIP_SIBLINGS return value
27 * @library ../..
28 * @compile SkipSiblings.java CreateFileTree.java
29 * @run main SkipSiblings
30 * @key randomness
31 */
32
33import java.nio.file.*;
34import java.nio.file.attribute.*;
35import java.io.IOException;
36import java.util.*;
37
38public class SkipSiblings {
39
40    static final Random rand = new Random();
41    static final Set<Path> skipped = new HashSet<Path>();
42
43    // check if this path's directory has been skipped
44    static void check(Path path) {
45        if (skipped.contains(path.getParent()))
46            throw new RuntimeException(path + " should not have been visited");
47    }
48
49    // indicates if the siblings of this path should be skipped
50    static boolean skip(Path path) {
51        Path parent = path.getParent();
52        if (parent != null && rand.nextBoolean()) {
53            skipped.add(parent);
54            return true;
55        }
56        return false;
57    }
58
59    public static void main(String[] args) throws Exception {
60        Path top = CreateFileTree.create();
61        try {
62            test(top);
63        } finally {
64            TestUtil.removeAll(top);
65        }
66    }
67
68    static void test(final Path start) throws IOException {
69        Files.walkFileTree(start, new SimpleFileVisitor<Path>() {
70            @Override
71            public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) {
72                check(dir);
73                if (skip(dir))
74                    return FileVisitResult.SKIP_SIBLINGS;
75                return FileVisitResult.CONTINUE;
76            }
77            @Override
78            public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
79                check(file);
80                if (skip(file))
81                    return FileVisitResult.SKIP_SIBLINGS;
82                return FileVisitResult.CONTINUE;
83            }
84            @Override
85            public FileVisitResult postVisitDirectory(Path dir, IOException x) {
86                if (x != null)
87                    throw new RuntimeException(x);
88                check(dir);
89                if (rand.nextBoolean()) {
90                    return FileVisitResult.CONTINUE;
91                } else {
92                    return FileVisitResult.SKIP_SIBLINGS;
93                }
94            }
95        });
96    }
97}
98