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
17package com.google.common.io;
18
19import java.io.ByteArrayInputStream;
20import java.io.IOException;
21import java.io.InputStream;
22
23/**
24 * Unit tests for {@link CountingInputStream}.
25 *
26 * @author Chris Nokleberg
27 */
28public class CountingInputStreamTest extends IoTestCase {
29  private CountingInputStream counter;
30
31  @Override protected void setUp() throws Exception {
32    super.setUp();
33    counter = new CountingInputStream(new ByteArrayInputStream(new byte[20]));
34  }
35
36  public void testReadSingleByte() throws IOException {
37    assertEquals(0, counter.getCount());
38    assertEquals(0, counter.read());
39    assertEquals(1, counter.getCount());
40  }
41
42  public void testReadArray() throws IOException {
43    assertEquals(10, counter.read(new byte[10]));
44    assertEquals(10, counter.getCount());
45  }
46
47  public void testReadArrayRange() throws IOException {
48    assertEquals(3, counter.read(new byte[10], 1, 3));
49    assertEquals(3, counter.getCount());
50  }
51
52  public void testSkip() throws IOException {
53    assertEquals(10, counter.skip(10));
54    assertEquals(10, counter.getCount());
55  }
56
57  public void testSkipEOF() throws IOException {
58    assertEquals(20, counter.skip(30));
59    assertEquals(20, counter.getCount());
60    assertEquals(0, counter.skip(20));
61    assertEquals(20, counter.getCount());
62
63    // Test reading a single byte while we're in the right state
64    assertEquals(-1, counter.read());
65    assertEquals(20, counter.getCount());
66  }
67
68  public void testReadArrayEOF() throws IOException {
69    assertEquals(20, counter.read(new byte[30]));
70    assertEquals(20, counter.getCount());
71    assertEquals(-1, counter.read(new byte[30]));
72    assertEquals(20, counter.getCount());
73  }
74
75  public void testMark() throws Exception {
76    assertTrue(counter.markSupported());
77    assertEquals(10, counter.read(new byte[10]));
78    assertEquals(10, counter.getCount());
79    counter.mark(5);
80    counter.read();
81    assertEquals(11, counter.getCount());
82    counter.reset();
83    assertEquals(10, counter.getCount());
84    assertEquals(10, counter.skip(100));
85    assertEquals(20, counter.getCount());
86  }
87
88  public void testMarkNotSet() {
89    try {
90      counter.reset();
91      fail();
92    } catch (IOException expected) {
93      assertEquals("Mark not set", expected.getMessage());
94    }
95  }
96
97  public void testMarkNotSupported() {
98    counter = new CountingInputStream(new UnmarkableInputStream());
99
100    try {
101      counter.reset();
102      fail();
103    } catch (IOException expected) {
104      assertEquals("Mark not supported", expected.getMessage());
105    }
106  }
107
108  private static class UnmarkableInputStream extends InputStream {
109    @Override
110    public int read() throws IOException {
111      return 0;
112    }
113
114    @Override
115    public boolean markSupported() {
116      return false;
117    }
118  }
119}
120