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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.testclassification.SmallTests;
27  import org.junit.Assert;
28  import org.junit.Test;
29  import org.junit.experimental.categories.Category;
30  
31  @Category(SmallTests.class)
32  public class TestVIntTool {
33  
34    @Test
35    public void testNumBytes() {
36      Assert.assertEquals(1, UVIntTool.numBytes(0));
37      Assert.assertEquals(1, UVIntTool.numBytes(1));
38      Assert.assertEquals(1, UVIntTool.numBytes(100));
39      Assert.assertEquals(1, UVIntTool.numBytes(126));
40      Assert.assertEquals(1, UVIntTool.numBytes(127));
41      Assert.assertEquals(2, UVIntTool.numBytes(128));
42      Assert.assertEquals(2, UVIntTool.numBytes(129));
43      Assert.assertEquals(5, UVIntTool.numBytes(Integer.MAX_VALUE));
44    }
45  
46    @Test
47    public void testWriteBytes() throws IOException {
48      Assert.assertArrayEquals(new byte[] { 0 }, bytesViaOutputStream(0));
49      Assert.assertArrayEquals(new byte[] { 1 }, bytesViaOutputStream(1));
50      Assert.assertArrayEquals(new byte[] { 63 }, bytesViaOutputStream(63));
51      Assert.assertArrayEquals(new byte[] { 127 }, bytesViaOutputStream(127));
52      Assert.assertArrayEquals(new byte[] { -128, 1 }, bytesViaOutputStream(128));
53      Assert.assertArrayEquals(new byte[] { -128 + 27, 1 }, bytesViaOutputStream(155));
54      Assert.assertArrayEquals(UVIntTool.MAX_VALUE_BYTES, bytesViaOutputStream(Integer.MAX_VALUE));
55    }
56  
57    private byte[] bytesViaOutputStream(int value) throws IOException {
58      ByteArrayOutputStream os = new ByteArrayOutputStream();
59      UVIntTool.writeBytes(value, os);
60      return os.toByteArray();
61    }
62  
63    @Test
64    public void testToBytes() {
65      Assert.assertArrayEquals(new byte[] { 0 }, UVIntTool.getBytes(0));
66      Assert.assertArrayEquals(new byte[] { 1 }, UVIntTool.getBytes(1));
67      Assert.assertArrayEquals(new byte[] { 63 }, UVIntTool.getBytes(63));
68      Assert.assertArrayEquals(new byte[] { 127 }, UVIntTool.getBytes(127));
69      Assert.assertArrayEquals(new byte[] { -128, 1 }, UVIntTool.getBytes(128));
70      Assert.assertArrayEquals(new byte[] { -128 + 27, 1 }, UVIntTool.getBytes(155));
71      Assert.assertArrayEquals(UVIntTool.MAX_VALUE_BYTES, UVIntTool.getBytes(Integer.MAX_VALUE));
72    }
73  
74    @Test
75    public void testFromBytes() {
76      Assert.assertEquals(Integer.MAX_VALUE, UVIntTool.getInt(UVIntTool.MAX_VALUE_BYTES));
77    }
78  
79    @Test
80    public void testRoundTrips() {
81      Random random = new Random();
82      for (int i = 0; i < 10000; ++i) {
83        int value = random.nextInt(Integer.MAX_VALUE);
84        byte[] bytes = UVIntTool.getBytes(value);
85        int roundTripped = UVIntTool.getInt(bytes);
86        Assert.assertEquals(value, roundTripped);
87      }
88    }
89  
90    @Test
91    public void testInputStreams() throws IOException {
92      ByteArrayInputStream is;
93      is = new ByteArrayInputStream(new byte[] { 0 });
94      Assert.assertEquals(0, UVIntTool.getInt(is));
95      is = new ByteArrayInputStream(new byte[] { 5 });
96      Assert.assertEquals(5, UVIntTool.getInt(is));
97      is = new ByteArrayInputStream(new byte[] { -128 + 27, 1 });
98      Assert.assertEquals(155, UVIntTool.getInt(is));
99    }
100 
101 }