1 /*
   2  * Copyright (c) 2000, 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  * @bug 4323074
  27  * @summary Basic test for new rotate algorithm
  28  * @key randomness
  29  */
  30 
  31 import java.util.*;
  32 
  33 public class Rotate {
  34     // Should have lots of distinct factors and be > ROTATE_THRESHOLD
  35     static final int SIZE = 120;
  36 
  37     static Random rnd = new Random();
  38 
  39     public static void main(String[] args) throws Exception {
  40         List a[] = {new ArrayList(), new LinkedList(), new Vector()};
  41 
  42         for (int i=0; i<a.length; i++) {
  43             List lst = a[i];
  44             for (int j=0; j<SIZE; j++)
  45                 lst.add(new Integer(j));
  46             int totalDist = 0;
  47 
  48             for (int j=0; j<10000; j++) {
  49                 int dist = rnd.nextInt(200) - 100;
  50                 Collections.rotate(lst, dist);
  51 
  52                 // Check that things are as they should be
  53                 totalDist = (totalDist + dist) % SIZE;
  54                 if (totalDist < 0)
  55                     totalDist += SIZE;
  56                 int index =0;
  57                 for (int k=totalDist; k<SIZE; k++, index++)
  58                     if (((Integer)lst.get(k)).intValue() != index)
  59                         throw new Exception("j: "+j+", lst["+k+"]="+lst.get(k)+
  60                                             ", should be "+index);
  61                 for (int k=0; k<totalDist; k++, index++)
  62                     if (((Integer)lst.get(k)).intValue() != index)
  63                         throw new Exception("j: "+j+", lst["+k+"]="+lst.get(k)+
  64                                             ", should be "+index);
  65             }
  66         }
  67     }
  68 }