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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  
19  package org.apache.hadoop.hbase.util.vint;
20  
21  import java.io.ByteArrayInputStream;
22  import java.io.ByteArrayOutputStream;
23  import java.io.IOException;
24  import java.util.Random;
25  
26  import org.apache.hadoop.hbase.SmallTests;
27  import org.apache.hadoop.hbase.util.vint.UVIntTool;
28  import org.junit.Assert;
29  import org.junit.Test;
30  import org.junit.experimental.categories.Category;
31  
32  @Category(SmallTests.class)
33  public class TestVIntTool {
34  
35    @Test
36    public void testNumBytes() {
37      Assert.assertEquals(1, UVIntTool.numBytes(0));
38      Assert.assertEquals(1, UVIntTool.numBytes(1));
39      Assert.assertEquals(1, UVIntTool.numBytes(100));
40      Assert.assertEquals(1, UVIntTool.numBytes(126));
41      Assert.assertEquals(1, UVIntTool.numBytes(127));
42      Assert.assertEquals(2, UVIntTool.numBytes(128));
43      Assert.assertEquals(2, UVIntTool.numBytes(129));
44      Assert.assertEquals(5, UVIntTool.numBytes(Integer.MAX_VALUE));
45    }
46  
47    @Test
48    public void testWriteBytes() throws IOException {
49      Assert.assertArrayEquals(new byte[] { 0 }, bytesViaOutputStream(0));
50      Assert.assertArrayEquals(new byte[] { 1 }, bytesViaOutputStream(1));
51      Assert.assertArrayEquals(new byte[] { 63 }, bytesViaOutputStream(63));
52      Assert.assertArrayEquals(new byte[] { 127 }, bytesViaOutputStream(127));
53      Assert.assertArrayEquals(new byte[] { -128, 1 }, bytesViaOutputStream(128));
54      Assert.assertArrayEquals(new byte[] { -128 + 27, 1 }, bytesViaOutputStream(155));
55      Assert.assertArrayEquals(UVIntTool.MAX_VALUE_BYTES, bytesViaOutputStream(Integer.MAX_VALUE));
56    }
57  
58    private byte[] bytesViaOutputStream(int value) throws IOException {
59      ByteArrayOutputStream os = new ByteArrayOutputStream();
60      UVIntTool.writeBytes(value, os);
61      return os.toByteArray();
62    }
63  
64    @Test
65    public void testToBytes() {
66      Assert.assertArrayEquals(new byte[] { 0 }, UVIntTool.getBytes(0));
67      Assert.assertArrayEquals(new byte[] { 1 }, UVIntTool.getBytes(1));
68      Assert.assertArrayEquals(new byte[] { 63 }, UVIntTool.getBytes(63));
69      Assert.assertArrayEquals(new byte[] { 127 }, UVIntTool.getBytes(127));
70      Assert.assertArrayEquals(new byte[] { -128, 1 }, UVIntTool.getBytes(128));
71      Assert.assertArrayEquals(new byte[] { -128 + 27, 1 }, UVIntTool.getBytes(155));
72      Assert.assertArrayEquals(UVIntTool.MAX_VALUE_BYTES, UVIntTool.getBytes(Integer.MAX_VALUE));
73    }
74  
75    @Test
76    public void testFromBytes() {
77      Assert.assertEquals(Integer.MAX_VALUE, UVIntTool.getInt(UVIntTool.MAX_VALUE_BYTES));
78    }
79  
80    @Test
81    public void testRoundTrips() {
82      Random random = new Random();
83      for (int i = 0; i < 10000; ++i) {
84        int value = random.nextInt(Integer.MAX_VALUE);
85        byte[] bytes = UVIntTool.getBytes(value);
86        int roundTripped = UVIntTool.getInt(bytes);
87        Assert.assertEquals(value, roundTripped);
88      }
89    }
90  
91    @Test
92    public void testInputStreams() throws IOException {
93      ByteArrayInputStream is;
94      is = new ByteArrayInputStream(new byte[] { 0 });
95      Assert.assertEquals(0, UVIntTool.getInt(is));
96      is = new ByteArrayInputStream(new byte[] { 5 });
97      Assert.assertEquals(5, UVIntTool.getInt(is));
98      is = new ByteArrayInputStream(new byte[] { -128 + 27, 1 });
99      Assert.assertEquals(155, UVIntTool.getInt(is));
100   }
101 
102 }