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  */
  31 
  32 import java.nio.file.*;
  33 import java.nio.file.attribute.*;
  34 import java.io.IOException;
  35 import java.util.*;
  36 
  37 public class SkipSiblings {
  38 
  39     static final Random rand = new Random();
  40     static final Set<Path> skipped = new HashSet<Path>();
  41 
  42     // check if this path's directory has been skipped
  43     static void check(Path path) {
  44         if (skipped.contains(path.getParent()))
  45             throw new RuntimeException(path + " should not have been visited");
  46     }
  47 
  48     // indicates if the siblings of this path should be skipped
  49     static boolean skip(Path path) {
  50         Path parent = path.getParent();
  51         if (parent != null && rand.nextBoolean()) {
  52             skipped.add(parent);
  53             return true;
  54         }
  55         return false;
  56     }
  57 
  58     public static void main(String[] args) throws Exception {
  59         Path top = CreateFileTree.create();
  60         try {
  61             test(top);
  62         } finally {
  63             TestUtil.removeAll(top);
  64         }
  65     }
  66 
  67     static void test(final Path start) throws IOException {
  68         Files.walkFileTree(start, new SimpleFileVisitor<Path>() {
  69             @Override
  70             public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) {
  71                 check(dir);
  72                 if (skip(dir))
  73                     return FileVisitResult.SKIP_SIBLINGS;
  74                 return FileVisitResult.CONTINUE;
  75             }
  76             @Override
  77             public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
  78                 check(file);
  79                 if (skip(file))
  80                     return FileVisitResult.SKIP_SIBLINGS;
  81                 return FileVisitResult.CONTINUE;
  82             }
  83             @Override
  84             public FileVisitResult postVisitDirectory(Path dir, IOException x) {
  85                 if (x != null)
  86                     throw new RuntimeException(x);
  87                 check(dir);
  88                 if (rand.nextBoolean()) {
  89                     return FileVisitResult.CONTINUE;
  90                 } else {
  91                     return FileVisitResult.SKIP_SIBLINGS;
  92                 }
  93             }
  94         });
  95     }
  96 }