MarkSupportedInputStream.java

/*-
 * #%L
 * io.earcam.utilitarian.io
 * %%
 * Copyright (C) 2017 earcam
 * %%
 * SPDX-License-Identifier: (BSD-3-Clause OR EPL-1.0 OR Apache-2.0 OR MIT)
 *
 * You <b>must</b> choose to accept, in full - any individual or combination of
 * the following licenses:
 * <ul>
 * 	<li><a href="https://opensource.org/licenses/BSD-3-Clause">BSD-3-Clause</a></li>
 * 	<li><a href="https://www.eclipse.org/legal/epl-v10.html">EPL-1.0</a></li>
 * 	<li><a href="https://www.apache.org/licenses/LICENSE-2.0">Apache-2.0</a></li>
 * 	<li><a href="https://opensource.org/licenses/MIT">MIT</a></li>
 * </ul>
 * #L%
 */
package io.earcam.utilitarian.io;

import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;

import javax.annotation.concurrent.NotThreadSafe;

/**
 * <p>
 * Wraps an {@link InputStream} to ensure {@link InputStream#markSupported()} returns {@code true}.
 * </p>
 *
 *
 * <p>
 * <b>Note:</b> if calls to {@link #read()} exceed the {@code readLimit} parameter of {@link #mark(int)}
 * then the mark is removed and a call to {@link #reset()} will throw an {@link IOException}.
 * </p>
 *
 */
@NotThreadSafe
public final class MarkSupportedInputStream extends InputStream {

	private int[] buffer = new int[0];
	private int readPosition = 0;
	private int writePosition = 0;
	private int readLimit = 0;
	private final InputStream delegate;


	/**
	 * Create an InputStream with mark supported
	 *
	 * @param delegate the {@link InputStream} to wrap
	 */
	public MarkSupportedInputStream(InputStream delegate)
	{
		this.delegate = delegate;
	}


	/**
	 * For efficient use of memory, this convenience static method
	 * returns the {@code input} argument IFF it claims to to support marking,
	 * otherwise the stream is wrapped
	 *
	 * @param input the {@link InputStream} to check
	 * @return an {@link InputStream} that supports marking
	 */
	public static InputStream ensureMarkSupported(InputStream input)
	{
		return input.markSupported() ? input : new MarkSupportedInputStream(input);
	}


	@Override
	public int read() throws IOException
	{
		if(writePosition == readLimit) {
			readPosition = writePosition = readLimit = 0;
			return delegate.read();
		}
		if(readPosition < writePosition) {
			return buffer[readPosition++];
		}
		int read = delegate.read();
		buffer[writePosition] = read;
		writePosition++;
		readPosition++;
		return read;
	}


	@Override
	public final boolean markSupported()
	{
		return true;
	}


	@Override
	public synchronized void mark(int readLimit)
	{
		this.readLimit = readLimit + 1;
		if(buffer.length < this.readLimit || readPosition > 0) {
			buffer = Arrays.copyOfRange(buffer, readPosition, readPosition + this.readLimit);
			writePosition -= readPosition;
		}
		readPosition = 0;
	}


	@Override
	public synchronized void reset() throws IOException
	{
		if(readLimit == 0) {
			throw new IOException("Not marked, or current position > marked position + readLimit");
		}
		readPosition = 0;
	}
}
















Active mutators

INCREMENTS_MUTATOR
VOID_METHOD_CALL_MUTATOR
RETURN_VALS_MUTATOR
MATH_MUTATOR
NEGATE_CONDITIONALS_MUTATOR
INVERT_NEGS_MUTATOR
CONDITIONALS_BOUNDARY_MUTATOR

Tests examined

io.earcam.utilitarian.io.ReplaceAllInputStreamTest.replaceSingleOccurrence() (3 ms)
io.earcam.utilitarian.io.MarkSupportedInputStreamTest.whenMarkExceedsLimitThenResetThrows() (3 ms)
io.earcam.utilitarian.io.ReplaceAllInputStreamTest.falseStartNoOccurrences() (3 ms)
io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() (2 ms)
io.earcam.utilitarian.io.MarkSupportedInputStreamTest.ensureMarkSupportedWrapsWhenUnderlyingDoesNotSupportMarking() (7 ms)
io.earcam.utilitarian.io.ReplaceAllInputStreamTest.mutlipleOccurrencesWithShorterReplacementThanSearch() (3 ms)
io.earcam.utilitarian.io.MarkSupportedInputStreamTest.increasingReadLimitMarksWithinReset() (5 ms)
io.earcam.utilitarian.io.MarkSupportedInputStreamTest.resetThrowsWhenNotAlreadyMarked() (3 ms)
io.earcam.utilitarian.io.ReplaceAllInputStreamTest.replaceSingleOccurrenceAtEnd() (4 ms)
io.earcam.utilitarian.io.ReplaceAllInputStreamTest.deleteMutlipleOccurrences() (3 ms)
io.earcam.utilitarian.io.MarkSupportedInputStreamTest.ensureMarkSupportedReturnsOriginalWhenOriginalSupportsMarking() (4 ms)
io.earcam.utilitarian.io.ReplaceAllInputStreamTest.replaceMutlipleOccurrences() (3 ms)
io.earcam.utilitarian.io.ReplaceAllInputStreamTest.replaceSingleOccurrenceAtStart() (4 ms)
io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markAndResetWithinLimit() (3 ms)

Report generated by PIT 1.4.3

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 Location : ensureMarkSupported Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.ensureMarkSupportedReturnsOriginalWhenOriginalSupportsMarking() negated conditional → KILLED 2.2 Location : ensureMarkSupported Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.ensureMarkSupportedReturnsOriginalWhenOriginalSupportsMarking() mutated return of Object value for io/earcam/utilitarian/io/MarkSupportedInputStream::ensureMarkSupported to ( if (x != null) null else throw new RuntimeException ) → KILLED
77		1.1 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() negated conditional → KILLED
79		1.1 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() replaced return of integer sized value with (x == 0 ? 1 : 0) → KILLED
81		1.1 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() changed conditional boundary → KILLED 2.2 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() negated conditional → KILLED
82		1.1 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.increasingReadLimitMarksWithinReset() Replaced integer addition with subtraction → KILLED 2.2 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markAndResetWithinLimit() replaced return of integer sized value with (x == 0 ? 1 : 0) → KILLED
86		1.1 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() Replaced integer addition with subtraction → KILLED
87		1.1 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() Replaced integer addition with subtraction → KILLED
88		1.1 Location : read Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() replaced return of integer sized value with (x == 0 ? 1 : 0) → KILLED
95		1.1 Location : markSupported Killed by : none replaced return of integer sized value with (x == 0 ? 1 : 0) → SURVIVED
102		1.1 Location : mark Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markAndResetWithinLimit() Replaced integer addition with subtraction → KILLED
103		1.1 Location : mark Killed by : none changed conditional boundary → SURVIVED 2.2 Location : mark Killed by : none changed conditional boundary → SURVIVED 3.3 Location : mark Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() negated conditional → KILLED 4.4 Location : mark Killed by : io.earcam.utilitarian.io.ReplaceAllInputStreamTest.deleteMutlipleOccurrences() negated conditional → KILLED
104		1.1 Location : mark Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markExceedsLimit() Replaced integer addition with subtraction → KILLED
105		1.1 Location : mark Killed by : io.earcam.utilitarian.io.ReplaceAllInputStreamTest.deleteMutlipleOccurrences() Replaced integer subtraction with addition → KILLED
114		1.1 Location : reset Killed by : io.earcam.utilitarian.io.MarkSupportedInputStreamTest.markAndResetWithinLimit() negated conditional → KILLED

MarkSupportedInputStream.java

Mutations

Active mutators

Tests examined