1 | /*- | |
2 | * #%L | |
3 | * io.earcam.utilitarian.io | |
4 | * %% | |
5 | * Copyright (C) 2017 earcam | |
6 | * %% | |
7 | * SPDX-License-Identifier: (BSD-3-Clause OR EPL-1.0 OR Apache-2.0 OR MIT) | |
8 | * | |
9 | * You <b>must</b> choose to accept, in full - any individual or combination of | |
10 | * the following licenses: | |
11 | * <ul> | |
12 | * <li><a href="https://opensource.org/licenses/BSD-3-Clause">BSD-3-Clause</a></li> | |
13 | * <li><a href="https://www.eclipse.org/legal/epl-v10.html">EPL-1.0</a></li> | |
14 | * <li><a href="https://www.apache.org/licenses/LICENSE-2.0">Apache-2.0</a></li> | |
15 | * <li><a href="https://opensource.org/licenses/MIT">MIT</a></li> | |
16 | * </ul> | |
17 | * #L% | |
18 | */ | |
19 | package io.earcam.utilitarian.io; | |
20 | ||
21 | import java.io.IOException; | |
22 | import java.io.InputStream; | |
23 | import java.util.Arrays; | |
24 | ||
25 | import javax.annotation.concurrent.NotThreadSafe; | |
26 | ||
27 | /** | |
28 | * <p> | |
29 | * Wraps an {@link InputStream} to ensure {@link InputStream#markSupported()} returns {@code true}. | |
30 | * </p> | |
31 | * | |
32 | * | |
33 | * <p> | |
34 | * <b>Note:</b> if calls to {@link #read()} exceed the {@code readLimit} parameter of {@link #mark(int)} | |
35 | * then the mark is removed and a call to {@link #reset()} will throw an {@link IOException}. | |
36 | * </p> | |
37 | * | |
38 | */ | |
39 | @NotThreadSafe | |
40 | public final class MarkSupportedInputStream extends InputStream { | |
41 | ||
42 | private int[] buffer = new int[0]; | |
43 | private int readPosition = 0; | |
44 | private int writePosition = 0; | |
45 | private int readLimit = 0; | |
46 | private final InputStream delegate; | |
47 | ||
48 | ||
49 | /** | |
50 | * Create an InputStream with mark supported | |
51 | * | |
52 | * @param delegate the {@link InputStream} to wrap | |
53 | */ | |
54 | public MarkSupportedInputStream(InputStream delegate) | |
55 | { | |
56 | this.delegate = delegate; | |
57 | } | |
58 | ||
59 | ||
60 | /** | |
61 | * For efficient use of memory, this convenience static method | |
62 | * returns the {@code input} argument IFF it claims to to support marking, | |
63 | * otherwise the stream is wrapped | |
64 | * | |
65 | * @param input the {@link InputStream} to check | |
66 | * @return an {@link InputStream} that supports marking | |
67 | */ | |
68 | public static InputStream ensureMarkSupported(InputStream input) | |
69 | { | |
70 |
2
1. ensureMarkSupported : negated conditional → KILLED 2. ensureMarkSupported : mutated return of Object value for io/earcam/utilitarian/io/MarkSupportedInputStream::ensureMarkSupported to ( if (x != null) null else throw new RuntimeException ) → KILLED |
return input.markSupported() ? input : new MarkSupportedInputStream(input); |
71 | } | |
72 | ||
73 | ||
74 | @Override | |
75 | public int read() throws IOException | |
76 | { | |
77 |
1
1. read : negated conditional → KILLED |
if(writePosition == readLimit) { |
78 | readPosition = writePosition = readLimit = 0; | |
79 |
1
1. read : replaced return of integer sized value with (x == 0 ? 1 : 0) → KILLED |
return delegate.read(); |
80 | } | |
81 |
2
1. read : changed conditional boundary → KILLED 2. read : negated conditional → KILLED |
if(readPosition < writePosition) { |
82 |
2
1. read : Replaced integer addition with subtraction → KILLED 2. read : replaced return of integer sized value with (x == 0 ? 1 : 0) → KILLED |
return buffer[readPosition++]; |
83 | } | |
84 | int read = delegate.read(); | |
85 | buffer[writePosition] = read; | |
86 |
1
1. read : Replaced integer addition with subtraction → KILLED |
writePosition++; |
87 |
1
1. read : Replaced integer addition with subtraction → KILLED |
readPosition++; |
88 |
1
1. read : replaced return of integer sized value with (x == 0 ? 1 : 0) → KILLED |
return read; |
89 | } | |
90 | ||
91 | ||
92 | @Override | |
93 | public final boolean markSupported() | |
94 | { | |
95 |
1
1. markSupported : replaced return of integer sized value with (x == 0 ? 1 : 0) → SURVIVED |
return true; |
96 | } | |
97 | ||
98 | ||
99 | @Override | |
100 | public synchronized void mark(int readLimit) | |
101 | { | |
102 |
1
1. mark : Replaced integer addition with subtraction → KILLED |
this.readLimit = readLimit + 1; |
103 |
4
1. mark : changed conditional boundary → SURVIVED 2. mark : changed conditional boundary → SURVIVED 3. mark : negated conditional → KILLED 4. mark : negated conditional → KILLED |
if(buffer.length < this.readLimit || readPosition > 0) { |
104 |
1
1. mark : Replaced integer addition with subtraction → KILLED |
buffer = Arrays.copyOfRange(buffer, readPosition, readPosition + this.readLimit); |
105 |
1
1. mark : Replaced integer subtraction with addition → KILLED |
writePosition -= readPosition; |
106 | } | |
107 | readPosition = 0; | |
108 | } | |
109 | ||
110 | ||
111 | @Override | |
112 | public synchronized void reset() throws IOException | |
113 | { | |
114 |
1
1. reset : negated conditional → KILLED |
if(readLimit == 0) { |
115 | throw new IOException("Not marked, or current position > marked position + readLimit"); | |
116 | } | |
117 | readPosition = 0; | |
118 | } | |
119 | } | |
Mutations | ||
70 |
1.1 2.2 |
|
77 |
1.1 |
|
79 |
1.1 |
|
81 |
1.1 2.2 |
|
82 |
1.1 2.2 |
|
86 |
1.1 |
|
87 |
1.1 |
|
88 |
1.1 |
|
95 |
1.1 |
|
102 |
1.1 |
|
103 |
1.1 2.2 3.3 4.4 |
|
104 |
1.1 |
|
105 |
1.1 |
|
114 |
1.1 |