1 /*

     2  * Copyright (c) 2008, 2010, 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 import java.nio.file.*;

    25 import java.nio.file.attribute.*;

    26 import java.io.IOException;

    27 import java.util.*;

    28 

    29 /**

    30  * Unit test for Files.walkFileTree to test SKIP_SIBLINGS return value.

    31  */

    32 

    33 public class SkipSiblings {

    34 

    35     static final Random rand = new Random();

    36     static final Set<Path> skipped = new HashSet<Path>();

    37 

    38     // check if this path's directory has been skipped

    39     static void check(Path path) {

    40         if (skipped.contains(path.getParent()))

    41             throw new RuntimeException(path + " should not have been visited");

    42     }

    43 

    44     // indicates if the siblings of this path should be skipped

    45     static boolean skip(Path path) {

    46         Path parent = path.getParent();

    47         if (parent != null && rand.nextBoolean()) {

    48             skipped.add(parent);

    49             return true;

    50         }

    51         return false;

    52     }

    53 

    54     public static void main(String[] args) throws Exception {

    55         Path dir = Paths.get(args[0]);

    56 

    57         Files.walkFileTree(dir, new SimpleFileVisitor<Path>() {

    58             @Override

    59             public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) {

    60                 check(dir);

    61                 if (skip(dir))

    62                     return FileVisitResult.SKIP_SIBLINGS;

    63                 return FileVisitResult.CONTINUE;

    64             }

    65             @Override

    66             public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {

    67                 check(file);

    68                 if (skip(file))

    69                     return FileVisitResult.SKIP_SIBLINGS;

    70                 return FileVisitResult.CONTINUE;

    71             }

    72             @Override

    73             public FileVisitResult postVisitDirectory(Path dir, IOException x) {

    74                 if (x != null)

    75                     throw new RuntimeException(x);

    76                 check(dir);

    77                 return FileVisitResult.CONTINUE;

    78             }

    79         });

    80     }

    81 }