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      1 /*
      2  * Copyright (C) 2008 The Guava Authors
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  * http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.google.common.primitives;
     18 
     19 import com.google.common.annotations.GwtCompatible;
     20 import com.google.common.annotations.GwtIncompatible;
     21 import com.google.common.collect.testing.Helpers;
     22 import com.google.common.testing.NullPointerTester;
     23 
     24 import junit.framework.TestCase;
     25 
     26 import java.util.Arrays;
     27 import java.util.Collection;
     28 import java.util.Collections;
     29 import java.util.List;
     30 
     31 /**
     32  * Unit test for {@link Bytes}.
     33  *
     34  * @author Kevin Bourrillion
     35  */
     36 @GwtCompatible(emulated = true)
     37 public class BytesTest extends TestCase {
     38   private static final byte[] EMPTY = {};
     39   private static final byte[] ARRAY1 = {(byte) 1};
     40   private static final byte[] ARRAY234
     41       = {(byte) 2, (byte) 3, (byte) 4};
     42 
     43   private static final byte[] VALUES =
     44       { Byte.MIN_VALUE, -1, 0, 1, Byte.MAX_VALUE };
     45 
     46   public void testHashCode() {
     47     for (byte value : VALUES) {
     48       assertEquals(((Byte) value).hashCode(), Bytes.hashCode(value));
     49     }
     50   }
     51 
     52   public void testContains() {
     53     assertFalse(Bytes.contains(EMPTY, (byte) 1));
     54     assertFalse(Bytes.contains(ARRAY1, (byte) 2));
     55     assertFalse(Bytes.contains(ARRAY234, (byte) 1));
     56     assertTrue(Bytes.contains(new byte[] {(byte) -1}, (byte) -1));
     57     assertTrue(Bytes.contains(ARRAY234, (byte) 2));
     58     assertTrue(Bytes.contains(ARRAY234, (byte) 3));
     59     assertTrue(Bytes.contains(ARRAY234, (byte) 4));
     60   }
     61 
     62   public void testIndexOf() {
     63     assertEquals(-1, Bytes.indexOf(EMPTY, (byte) 1));
     64     assertEquals(-1, Bytes.indexOf(ARRAY1, (byte) 2));
     65     assertEquals(-1, Bytes.indexOf(ARRAY234, (byte) 1));
     66     assertEquals(0, Bytes.indexOf(
     67         new byte[] {(byte) -1}, (byte) -1));
     68     assertEquals(0, Bytes.indexOf(ARRAY234, (byte) 2));
     69     assertEquals(1, Bytes.indexOf(ARRAY234, (byte) 3));
     70     assertEquals(2, Bytes.indexOf(ARRAY234, (byte) 4));
     71     assertEquals(1, Bytes.indexOf(
     72         new byte[] { (byte) 2, (byte) 3, (byte) 2, (byte) 3 },
     73         (byte) 3));
     74   }
     75 
     76   public void testIndexOf_arrayTarget() {
     77     assertEquals(0, Bytes.indexOf(EMPTY, EMPTY));
     78     assertEquals(0, Bytes.indexOf(ARRAY234, EMPTY));
     79     assertEquals(-1, Bytes.indexOf(EMPTY, ARRAY234));
     80     assertEquals(-1, Bytes.indexOf(ARRAY234, ARRAY1));
     81     assertEquals(-1, Bytes.indexOf(ARRAY1, ARRAY234));
     82     assertEquals(0, Bytes.indexOf(ARRAY1, ARRAY1));
     83     assertEquals(0, Bytes.indexOf(ARRAY234, ARRAY234));
     84     assertEquals(0, Bytes.indexOf(
     85         ARRAY234, new byte[] { (byte) 2, (byte) 3 }));
     86     assertEquals(1, Bytes.indexOf(
     87         ARRAY234, new byte[] { (byte) 3, (byte) 4 }));
     88     assertEquals(1, Bytes.indexOf(ARRAY234, new byte[] { (byte) 3 }));
     89     assertEquals(2, Bytes.indexOf(ARRAY234, new byte[] { (byte) 4 }));
     90     assertEquals(1, Bytes.indexOf(new byte[] { (byte) 2, (byte) 3,
     91         (byte) 3, (byte) 3, (byte) 3 },
     92         new byte[] { (byte) 3 }
     93     ));
     94     assertEquals(2, Bytes.indexOf(
     95         new byte[] { (byte) 2, (byte) 3, (byte) 2,
     96             (byte) 3, (byte) 4, (byte) 2, (byte) 3},
     97         new byte[] { (byte) 2, (byte) 3, (byte) 4}
     98     ));
     99     assertEquals(1, Bytes.indexOf(
    100         new byte[] { (byte) 2, (byte) 2, (byte) 3,
    101             (byte) 4, (byte) 2, (byte) 3, (byte) 4},
    102         new byte[] { (byte) 2, (byte) 3, (byte) 4}
    103     ));
    104     assertEquals(-1, Bytes.indexOf(
    105         new byte[] { (byte) 4, (byte) 3, (byte) 2},
    106         new byte[] { (byte) 2, (byte) 3, (byte) 4}
    107     ));
    108   }
    109 
    110   public void testLastIndexOf() {
    111     assertEquals(-1, Bytes.lastIndexOf(EMPTY, (byte) 1));
    112     assertEquals(-1, Bytes.lastIndexOf(ARRAY1, (byte) 2));
    113     assertEquals(-1, Bytes.lastIndexOf(ARRAY234, (byte) 1));
    114     assertEquals(0, Bytes.lastIndexOf(
    115         new byte[] {(byte) -1}, (byte) -1));
    116     assertEquals(0, Bytes.lastIndexOf(ARRAY234, (byte) 2));
    117     assertEquals(1, Bytes.lastIndexOf(ARRAY234, (byte) 3));
    118     assertEquals(2, Bytes.lastIndexOf(ARRAY234, (byte) 4));
    119     assertEquals(3, Bytes.lastIndexOf(
    120         new byte[] { (byte) 2, (byte) 3, (byte) 2, (byte) 3 },
    121         (byte) 3));
    122   }
    123 
    124   public void testConcat() {
    125     assertTrue(Arrays.equals(EMPTY, Bytes.concat()));
    126     assertTrue(Arrays.equals(EMPTY, Bytes.concat(EMPTY)));
    127     assertTrue(Arrays.equals(EMPTY, Bytes.concat(EMPTY, EMPTY, EMPTY)));
    128     assertTrue(Arrays.equals(ARRAY1, Bytes.concat(ARRAY1)));
    129     assertNotSame(ARRAY1, Bytes.concat(ARRAY1));
    130     assertTrue(Arrays.equals(ARRAY1, Bytes.concat(EMPTY, ARRAY1, EMPTY)));
    131     assertTrue(Arrays.equals(
    132         new byte[] {(byte) 1, (byte) 1, (byte) 1},
    133         Bytes.concat(ARRAY1, ARRAY1, ARRAY1)));
    134     assertTrue(Arrays.equals(
    135         new byte[] {(byte) 1, (byte) 2, (byte) 3, (byte) 4},
    136         Bytes.concat(ARRAY1, ARRAY234)));
    137   }
    138 
    139   public void testEnsureCapacity() {
    140     assertSame(EMPTY, Bytes.ensureCapacity(EMPTY, 0, 1));
    141     assertSame(ARRAY1, Bytes.ensureCapacity(ARRAY1, 0, 1));
    142     assertSame(ARRAY1, Bytes.ensureCapacity(ARRAY1, 1, 1));
    143     assertTrue(Arrays.equals(
    144         new byte[] {(byte) 1, (byte) 0, (byte) 0},
    145         Bytes.ensureCapacity(ARRAY1, 2, 1)));
    146   }
    147 
    148   public void testEnsureCapacity_fail() {
    149     try {
    150       Bytes.ensureCapacity(ARRAY1, -1, 1);
    151       fail();
    152     } catch (IllegalArgumentException expected) {
    153     }
    154     try {
    155       // notice that this should even fail when no growth was needed
    156       Bytes.ensureCapacity(ARRAY1, 1, -1);
    157       fail();
    158     } catch (IllegalArgumentException expected) {
    159     }
    160   }
    161 
    162   public void testToArray() {
    163     // need explicit type parameter to avoid javac warning!?
    164     List<Byte> none = Arrays.<Byte>asList();
    165     assertTrue(Arrays.equals(EMPTY, Bytes.toArray(none)));
    166 
    167     List<Byte> one = Arrays.asList((byte) 1);
    168     assertTrue(Arrays.equals(ARRAY1, Bytes.toArray(one)));
    169 
    170     byte[] array = {(byte) 0, (byte) 1, (byte) 0x55};
    171 
    172     List<Byte> three = Arrays.asList((byte) 0, (byte) 1, (byte) 0x55);
    173     assertTrue(Arrays.equals(array, Bytes.toArray(three)));
    174 
    175     assertTrue(Arrays.equals(array, Bytes.toArray(Bytes.asList(array))));
    176   }
    177 
    178   public void testToArray_threadSafe() {
    179     for (int delta : new int[] { +1, 0, -1 }) {
    180       for (int i = 0; i < VALUES.length; i++) {
    181         List<Byte> list = Bytes.asList(VALUES).subList(0, i);
    182         Collection<Byte> misleadingSize =
    183             Helpers.misleadingSizeCollection(delta);
    184         misleadingSize.addAll(list);
    185         byte[] arr = Bytes.toArray(misleadingSize);
    186         assertEquals(i, arr.length);
    187         for (int j = 0; j < i; j++) {
    188           assertEquals(VALUES[j], arr[j]);
    189         }
    190       }
    191     }
    192   }
    193 
    194   public void testToArray_withNull() {
    195     List<Byte> list = Arrays.asList((byte) 0, (byte) 1, null);
    196     try {
    197       Bytes.toArray(list);
    198       fail();
    199     } catch (NullPointerException expected) {
    200     }
    201   }
    202 
    203   public void testToArray_withConversion() {
    204     byte[] array = {(byte) 0, (byte) 1, (byte) 2};
    205 
    206     List<Byte> bytes = Arrays.asList((byte) 0, (byte) 1, (byte) 2);
    207     List<Short> shorts = Arrays.asList((short) 0, (short) 1, (short) 2);
    208     List<Integer> ints = Arrays.asList(0, 1, 2);
    209     List<Float> floats = Arrays.asList((float) 0, (float) 1, (float) 2);
    210     List<Long> longs = Arrays.asList((long) 0, (long) 1, (long) 2);
    211     List<Double> doubles = Arrays.asList((double) 0, (double) 1, (double) 2);
    212 
    213     assertTrue(Arrays.equals(array, Bytes.toArray(bytes)));
    214     assertTrue(Arrays.equals(array, Bytes.toArray(shorts)));
    215     assertTrue(Arrays.equals(array, Bytes.toArray(ints)));
    216     assertTrue(Arrays.equals(array, Bytes.toArray(floats)));
    217     assertTrue(Arrays.equals(array, Bytes.toArray(longs)));
    218     assertTrue(Arrays.equals(array, Bytes.toArray(doubles)));
    219   }
    220 
    221   public void testAsList_isAView() {
    222     byte[] array = {(byte) 0, (byte) 1};
    223     List<Byte> list = Bytes.asList(array);
    224     list.set(0, (byte) 2);
    225     assertTrue(Arrays.equals(new byte[] {(byte) 2, (byte) 1}, array));
    226     array[1] = (byte) 3;
    227     assertEquals(Arrays.asList((byte) 2, (byte) 3), list);
    228   }
    229 
    230   public void testAsList_toArray_roundTrip() {
    231     byte[] array = { (byte) 0, (byte) 1, (byte) 2 };
    232     List<Byte> list = Bytes.asList(array);
    233     byte[] newArray = Bytes.toArray(list);
    234 
    235     // Make sure it returned a copy
    236     list.set(0, (byte) 4);
    237     assertTrue(Arrays.equals(
    238         new byte[] { (byte) 0, (byte) 1, (byte) 2 }, newArray));
    239     newArray[1] = (byte) 5;
    240     assertEquals((byte) 1, (byte) list.get(1));
    241   }
    242 
    243   // This test stems from a real bug found by andrewk
    244   public void testAsList_subList_toArray_roundTrip() {
    245     byte[] array = { (byte) 0, (byte) 1, (byte) 2, (byte) 3 };
    246     List<Byte> list = Bytes.asList(array);
    247     assertTrue(Arrays.equals(new byte[] { (byte) 1, (byte) 2 },
    248         Bytes.toArray(list.subList(1, 3))));
    249     assertTrue(Arrays.equals(new byte[] {},
    250         Bytes.toArray(list.subList(2, 2))));
    251   }
    252 
    253   public void testAsListEmpty() {
    254     assertSame(Collections.emptyList(), Bytes.asList(EMPTY));
    255   }
    256 
    257   @GwtIncompatible("NullPointerTester")
    258   public void testNulls() {
    259     new NullPointerTester().testAllPublicStaticMethods(Bytes.class);
    260   }
    261 }
    262