1 /*
   2  * Copyright (c) 2012, 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 import org.testng.annotations.DataProvider;
  25 import org.testng.annotations.Test;
  26 
  27 import java.lang.Integer;
  28 import java.lang.Object;
  29 import java.lang.System;
  30 import java.util.BitSet;
  31 import java.util.OptionalInt;
  32 import java.util.PrimitiveIterator;
  33 import java.util.Random;
  34 import java.util.function.IntSupplier;
  35 import java.util.stream.Collectors;
  36 import java.util.stream.IntStream;
  37 
  38 import static org.testng.Assert.assertEquals;
  39 import static org.testng.Assert.assertFalse;
  40 import static org.testng.Assert.assertTrue;
  41 import static org.testng.Assert.fail;
  42 
  43 /**
  44  * @test
  45  * @summary test BitSet stream
  46  * @bug 8012645
  47  * @run testng BitSetStreamTest
  48  */
  49 public class BitSetStreamTest {
  50     static class Fibs implements IntSupplier {
  51         private int n1 = 0;
  52         private int n2 = 1;
  53 
  54         static int fibs(int n) {
  55             Fibs f = new Fibs();
  56             while (n-- > 0) f.getAsInt();
  57             return f.getAsInt();
  58         }
  59 
  60         public int getAsInt() { int s = n1; n1 = n2; n2 = s + n1; return s; }
  61     }
  62 
  63     private static final Object[][] testcases = new Object[][] {
  64         { "none", IntStream.empty() },
  65         { "index 0", IntStream.of(0) },
  66         { "index 255", IntStream.of(255) },
  67         { "every bit", IntStream.range(0, 255) },
  68         { "step 2", IntStream.range(0, 255, 2) },
  69         { "step 3", IntStream.range(0, 255, 3) },
  70         { "step 5", IntStream.range(0, 255, 5) },
  71         { "step 7", IntStream.range(0, 255, 7) },
  72         { "1, 10, 100, 1000", IntStream.of(1, 10, 100, 1000) },
  73         { "25 fibs", IntStream.generate(new Fibs()).limit(25) }
  74     };
  75 
  76     @DataProvider(name = "cases")
  77     public static Object[][] produceCases() {
  78         return testcases;
  79     }
  80 
  81     @Test
  82     public void testFibs() {
  83         Fibs f = new Fibs();
  84         assertEquals(0, f.getAsInt());
  85         assertEquals(1, f.getAsInt());
  86         assertEquals(1, f.getAsInt());
  87         assertEquals(2, f.getAsInt());
  88         assertEquals(3, f.getAsInt());
  89         assertEquals(5, f.getAsInt());
  90         assertEquals(8, f.getAsInt());
  91         assertEquals(13, f.getAsInt());
  92         assertEquals(987, Fibs.fibs(16));
  93     }
  94 
  95     @Test(dataProvider = "cases")
  96     public void testBitsetStream(String name, IntStream data) {
  97         BitSet bs = new BitSet();
  98         long setBits = data.distinct()
  99                            .peek(i -> bs.set(i))
 100                            .count();
 101 
 102         assertEquals(bs.cardinality(), setBits);
 103         assertEquals(bs.cardinality(), bs.stream().reduce(0, (s, i) -> s+1));
 104 
 105         PrimitiveIterator.OfInt it = bs.stream().iterator();
 106         for (int i = bs.nextSetBit(0); i >= 0; i = bs.nextSetBit(i+1)) {
 107             assertTrue(it.hasNext());
 108             assertEquals(it.nextInt(), i);
 109         }
 110         assertFalse(it.hasNext());
 111     }
 112 
 113     @Test
 114     public void testRandomStream() {
 115         final int size = 1024 * 1024;
 116         final int[] seeds = {
 117                 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41,
 118                 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97};
 119         final byte[] bytes = new byte[size];
 120         for (int seed : seeds) {
 121             final Random random = new Random(seed);
 122             random.nextBytes(bytes);
 123             final BitSet bitSet = BitSet.valueOf(bytes);
 124             final int cardinality = bitSet.cardinality();
 125             final IntStream stream = bitSet.stream();
 126             final int[] array = stream.toArray();
 127             assertEquals(array.length, cardinality);
 128             int nextSetBit = -1;
 129             for (int i=0; i < cardinality; i++) {
 130                 nextSetBit = bitSet.nextSetBit(nextSetBit + 1);
 131                 assertEquals(array[i], nextSetBit);
 132             }
 133         }
 134     }
 135 }