StringUtils.java

package com.renomad.minum.utils;

import java.net.URLDecoder;
import java.net.URLEncoder;
import java.security.SecureRandom;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

import static com.renomad.minum.utils.Invariants.mustNotBeNull;
import static java.nio.charset.StandardCharsets.UTF_8;

/**
 * Some helper methods for Strings.
 */
public final class StringUtils {

    private StringUtils() {
        // making this private to be clearer it isn't supposed to be instantiated.
    }


    /**
     * Returns text that has three symbols replaced -
     * the less-than, greater-than, and ampersand.
     * See <a href="https://www.w3.org/International/questions/qa-escapes#use">...</a>
     * <br>
     * <pre>{@code
     * This will protect against something like <div>$USERNAME</div> allowing
     * a username of
     *      <script>alert(1)</script>
     * becoming
     *      <div><script>alert(1)</script</div>
     * and instead becomes
     *      <div>&lt;script&gt;alert(1)&lt;/script&gt;</div>
     * }</pre>
     * If the text is going inside an attribute (e.g. {@code <div class="TEXT_GOES_HERE">} )
     * Then you need to escape slightly differently. In that case see [safeAttr]
     */
    public static String safeHtml(String input) {
        if (input == null) {
            return "";
        }
        return input.replace("&", "&amp;")
            .replace("<", "&lt;")
            .replace(">", "&gt;");
    }

    /**
     * Replace dangerous text that would go inside an HTML attribute.
     * See {@link #safeHtml(String)}
     * <br><br>
     * If we get a null string, just return an empty string
     * <br><br>
     * <p>
     *     Note: When cleaning data which will be used in an HTML
     *     attribute, ensure that the output of this method will
     *     be placed inside single or double quotes. <br><br>
     *
     *     Valid use: the key word HERE in the following: {@code <foo class="HERE">} or
     *     {@code <foo class='HERE'>}<br><br>
     *
     *     Invalid use: {@code <foo class=HERE>}
     * </p>
     * <pre>{@code
     * example:
     *   Given
     *      alert('XSS Attack')
     *   Get
     *      alert(&apos;XSS Attack&apos;)
     * }</pre>
     */
    public static String safeAttr(String input) {
        if (input == null) {
            return "";
        }
        return input.replace("&", "&amp;")
            .replace("<", "&lt;")
            .replace("\"", "&quot;")
            .replace("'", "&apos;");
    }

    /**
     * Encodes UTF-8 text using URL-encoding
     */
    public static String encode(String str) {
        if (str == null) {
            return "%NULL%";
        }
        return URLEncoder.encode(str, UTF_8);
    }

    /**
     * Decodes URL-encoded UTF-8 text, except that we
     * first check if the string value is the token %NULL%,
     * which is our way to signify null.
     */
    public static String decode(String str) {
        mustNotBeNull(str);
        if (str.equals("%NULL%")) {
            return null;
        }
        return URLDecoder.decode(str, UTF_8);
    }

    /**
     * Returns a string of random characters.
     * @param length a positive non-zero number less than 1000
     */
    public static String generateSecureRandomString(int length) {
        int maximum = 1000;
        if (length <= 0) {
            throw new UtilsException("Input must be a positive non-zero number");
        }
        if (length > maximum) {
            throw new UtilsException("Input must be less than " + maximum);
        }
        final var allowedChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
        final var sr = new SecureRandom();

        return IntStream.range(1, length+1)
                .mapToObj (x -> allowedChars.charAt(sr.nextInt(allowedChars.length())))
                .map(Object::toString)
                .collect(Collectors.joining());
    }

    /**
     * Converts a list of bytes to a string. Returns null if the input is null.
     */
    public static String byteListToString(List<Byte> byteList) {
        if (byteList == null) return null;
        final int size = byteList.size();
        final var buf = new byte[size];
        for (int i = 0; i < size; i++) {
            buf[i] = byteList.get(i);
        }
        return new String(buf, UTF_8);
    }

    /**
     * Converts an array of bytes to a string. Returns null if the input is null.
     */
    public static String byteArrayToString(byte[] byteArray) {
        if (byteArray == null) return null;
        return new String(byteArray, UTF_8);
    }

    /**
     * A helper method to assess whether the input consists of only digits.
     * This helps us in the case of checking the content-length header, since
     * it must be pure numbers, no "-" or "+" symbols preceding it.
     * @return true if the given string consists exclusively of digits, like "1234",
     * false if anything else, like "+1234" or "12.34" or "" or null.
     */
    public static boolean isPureDigits(String str) {
        if (str == null || str.isEmpty()) {
            return false;
        }
        for (int i = 0; i < str.length(); i++) {
            char c = str.charAt(i);
            if (c < '0' || c > '9') {
                return false;
            }
        }
        return true;
    }


}




























Active mutators

CONDITIONALS_BOUNDARY
EMPTY_RETURNS
FALSE_RETURNS
INCREMENTS
INVERT_NEGS
MATH
NEGATE_CONDITIONALS
NULL_RETURNS
PRIMITIVE_RETURNS
TRUE_RETURNS
VOID_METHOD_CALLS

Tests examined

com.renomad.minum.utils.StringUtilsTests (47 ms)
com.renomad.minum.web.BodyProcessorTests (133 ms)
com.renomad.minum.FunctionalTests.test_PathFunction_Response_Range(com.renomad.minum.FunctionalTests) (636 ms)
com.renomad.minum.FunctionalTests.test_PathFunction_Response(com.renomad.minum.FunctionalTests) (638 ms)
com.renomad.minum.web.WebTests (637 ms)
com.renomad.minum.FunctionalTests.testEndToEnd_Functional(com.renomad.minum.FunctionalTests) (2350 ms)
com.renomad.minum.utils.SerializationUtilsTests (3 ms)
com.renomad.minum.database.FindingsDatabaseTests (865 ms)
com.renomad.minum.database.IndexRaceBugTest.test_ConcurrentWritesSameIndexKey_ShouldNotCorrupt(com.renomad.minum.database.IndexRaceBugTest) (1996 ms)
com.renomad.minum.security.TheBrigTests (1910 ms)
com.renomad.minum.database.DbEngine2Tests (7983 ms)
com.renomad.minum.database.DbTests (9356 ms)
com.renomad.minum.web.HeadersTests (30 ms)
com.renomad.minum.web.RequestTests (189 ms)
com.renomad.minum.web.FindingsWebTests (529 ms)
com.renomad.minum.web.WebPerformanceTests.webPerfTest(com.renomad.minum.web.WebPerformanceTests) (631 ms)
com.renomad.minum.FunctionalTests.test_EdgeCase_Response_MultiCookies(com.renomad.minum.FunctionalTests) (620 ms)
com.renomad.minum.FunctionalTests.test_EdgeCase_PostHandler_IgnoreBody(com.renomad.minum.FunctionalTests) (652 ms)
com.renomad.minum.utils.FindingsUtilsTests (887 ms)

Report generated by PIT 1.17.0

1		package com.renomad.minum.utils;
2
3		import java.net.URLDecoder;
4		import java.net.URLEncoder;
5		import java.security.SecureRandom;
6		import java.util.List;
7		import java.util.stream.Collectors;
8		import java.util.stream.IntStream;
9
10		import static com.renomad.minum.utils.Invariants.mustNotBeNull;
11		import static java.nio.charset.StandardCharsets.UTF_8;
12
13		/**
14		* Some helper methods for Strings.
15		*/
16		public final class StringUtils {
17
18		private StringUtils() {
19		// making this private to be clearer it isn't supposed to be instantiated.
20		}
21
22
23		/**
24		* Returns text that has three symbols replaced -
25		* the less-than, greater-than, and ampersand.
26		* See <a href="https://www.w3.org/International/questions/qa-escapes#use">...</a>
27		* <br>
28		* <pre>{@code
29		* This will protect against something like <div>$USERNAME</div> allowing
30		* a username of
31		* <script>alert(1)</script>
32		* becoming
33		* <div><script>alert(1)</script</div>
34		* and instead becomes
35		* <div><script>alert(1)</script></div>
36		* }</pre>
37		* If the text is going inside an attribute (e.g. {@code <div class="TEXT_GOES_HERE">} )
38		* Then you need to escape slightly differently. In that case see [safeAttr]
39		*/
40		public static String safeHtml(String input) {
41	1 1. safeHtml : negated conditional → KILLED	if (input == null) {
42		return "";
43		}
44	1 1. safeHtml : replaced return value with "" for com/renomad/minum/utils/StringUtils::safeHtml → KILLED	return input.replace("&", "&")
45		.replace("<", "<")
46		.replace(">", ">");
47		}
48
49		/**
50		* Replace dangerous text that would go inside an HTML attribute.
51		* See {@link #safeHtml(String)}
52		* <br><br>
53		* If we get a null string, just return an empty string
54		* <br><br>
55		* <p>
56		* Note: When cleaning data which will be used in an HTML
57		* attribute, ensure that the output of this method will
58		* be placed inside single or double quotes. <br><br>
59		*
60		* Valid use: the key word HERE in the following: {@code <foo class="HERE">} or
61		* {@code <foo class='HERE'>}<br><br>
62		*
63		* Invalid use: {@code <foo class=HERE>}
64		* </p>
65		* <pre>{@code
66		* example:
67		* Given
68		* alert('XSS Attack')
69		* Get
70		* alert('XSS Attack')
71		* }</pre>
72		*/
73		public static String safeAttr(String input) {
74	1 1. safeAttr : negated conditional → KILLED	if (input == null) {
75		return "";
76		}
77	1 1. safeAttr : replaced return value with "" for com/renomad/minum/utils/StringUtils::safeAttr → KILLED	return input.replace("&", "&")
78		.replace("<", "<")
79		.replace("\"", """)
80		.replace("'", "'");
81		}
82
83		/**
84		* Encodes UTF-8 text using URL-encoding
85		*/
86		public static String encode(String str) {
87	1 1. encode : negated conditional → KILLED	if (str == null) {
88	1 1. encode : replaced return value with "" for com/renomad/minum/utils/StringUtils::encode → KILLED	return "%NULL%";
89		}
90	1 1. encode : replaced return value with "" for com/renomad/minum/utils/StringUtils::encode → KILLED	return URLEncoder.encode(str, UTF_8);
91		}
92
93		/**
94		* Decodes URL-encoded UTF-8 text, except that we
95		* first check if the string value is the token %NULL%,
96		* which is our way to signify null.
97		*/
98		public static String decode(String str) {
99		mustNotBeNull(str);
100	1 1. decode : negated conditional → KILLED	if (str.equals("%NULL%")) {
101	1 1. decode : replaced return value with "" for com/renomad/minum/utils/StringUtils::decode → TIMED_OUT	return null;
102		}
103	1 1. decode : replaced return value with "" for com/renomad/minum/utils/StringUtils::decode → KILLED	return URLDecoder.decode(str, UTF_8);
104		}
105
106		/**
107		* Returns a string of random characters.
108		* @param length a positive non-zero number less than 1000
109		*/
110		public static String generateSecureRandomString(int length) {
111		int maximum = 1000;
112	2 1. generateSecureRandomString : negated conditional → KILLED 2. generateSecureRandomString : changed conditional boundary → KILLED	if (length <= 0) {
113		throw new UtilsException("Input must be a positive non-zero number");
114		}
115	2 1. generateSecureRandomString : changed conditional boundary → KILLED 2. generateSecureRandomString : negated conditional → KILLED	if (length > maximum) {
116		throw new UtilsException("Input must be less than " + maximum);
117		}
118		final var allowedChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
119		final var sr = new SecureRandom();
120
121	2 1. generateSecureRandomString : Replaced integer addition with subtraction → KILLED 2. generateSecureRandomString : replaced return value with "" for com/renomad/minum/utils/StringUtils::generateSecureRandomString → KILLED	return IntStream.range(1, length+1)
122	1 1. lambda$generateSecureRandomString$0 : replaced Character return value with 0 for com/renomad/minum/utils/StringUtils::lambda$generateSecureRandomString$0 → KILLED	.mapToObj (x -> allowedChars.charAt(sr.nextInt(allowedChars.length())))
123		.map(Object::toString)
124		.collect(Collectors.joining());
125		}
126
127		/**
128		* Converts a list of bytes to a string. Returns null if the input is null.
129		*/
130		public static String byteListToString(List<Byte> byteList) {
131	2 1. byteListToString : negated conditional → KILLED 2. byteListToString : replaced return value with "" for com/renomad/minum/utils/StringUtils::byteListToString → KILLED	if (byteList == null) return null;
132		final int size = byteList.size();
133		final var buf = new byte[size];
134	2 1. byteListToString : changed conditional boundary → KILLED 2. byteListToString : negated conditional → KILLED	for (int i = 0; i < size; i++) {
135		buf[i] = byteList.get(i);
136		}
137	1 1. byteListToString : replaced return value with "" for com/renomad/minum/utils/StringUtils::byteListToString → KILLED	return new String(buf, UTF_8);
138		}
139
140		/**
141		* Converts an array of bytes to a string. Returns null if the input is null.
142		*/
143		public static String byteArrayToString(byte[] byteArray) {
144	2 1. byteArrayToString : negated conditional → KILLED 2. byteArrayToString : replaced return value with "" for com/renomad/minum/utils/StringUtils::byteArrayToString → KILLED	if (byteArray == null) return null;
145	1 1. byteArrayToString : replaced return value with "" for com/renomad/minum/utils/StringUtils::byteArrayToString → KILLED	return new String(byteArray, UTF_8);
146		}
147
148		/**
149		* A helper method to assess whether the input consists of only digits.
150		* This helps us in the case of checking the content-length header, since
151		* it must be pure numbers, no "-" or "+" symbols preceding it.
152		* @return true if the given string consists exclusively of digits, like "1234",
153		* false if anything else, like "+1234" or "12.34" or "" or null.
154		*/
155		public static boolean isPureDigits(String str) {
156	2 1. isPureDigits : negated conditional → KILLED 2. isPureDigits : negated conditional → KILLED	if (str == null \|\| str.isEmpty()) {
157	1 1. isPureDigits : replaced boolean return with true for com/renomad/minum/utils/StringUtils::isPureDigits → KILLED	return false;
158		}
159	2 1. isPureDigits : changed conditional boundary → KILLED 2. isPureDigits : negated conditional → KILLED	for (int i = 0; i < str.length(); i++) {
160		char c = str.charAt(i);
161	4 1. isPureDigits : changed conditional boundary → KILLED 2. isPureDigits : negated conditional → KILLED 3. isPureDigits : changed conditional boundary → KILLED 4. isPureDigits : negated conditional → KILLED	if (c < '0' \|\| c > '9') {
162	1 1. isPureDigits : replaced boolean return with true for com/renomad/minum/utils/StringUtils::isPureDigits → KILLED	return false;
163		}
164		}
165	1 1. isPureDigits : replaced boolean return with false for com/renomad/minum/utils/StringUtils::isPureDigits → KILLED	return true;
166		}
167
168
169		}
170
		Mutations
41		1.1 Location : safeHtml Killed by : com.renomad.minum.utils.StringUtilsTests negated conditional → KILLED
44		1.1 Location : safeHtml Killed by : com.renomad.minum.utils.StringUtilsTests replaced return value with "" for com/renomad/minum/utils/StringUtils::safeHtml → KILLED
74		1.1 Location : safeAttr Killed by : com.renomad.minum.utils.StringUtilsTests negated conditional → KILLED
77		1.1 Location : safeAttr Killed by : com.renomad.minum.utils.StringUtilsTests replaced return value with "" for com/renomad/minum/utils/StringUtils::safeAttr → KILLED
87		1.1 Location : encode Killed by : com.renomad.minum.utils.SerializationUtilsTests negated conditional → KILLED
88		1.1 Location : encode Killed by : com.renomad.minum.utils.SerializationUtilsTests replaced return value with "" for com/renomad/minum/utils/StringUtils::encode → KILLED
90		1.1 Location : encode Killed by : com.renomad.minum.utils.SerializationUtilsTests replaced return value with "" for com/renomad/minum/utils/StringUtils::encode → KILLED
100		1.1 Location : decode Killed by : com.renomad.minum.web.BodyProcessorTests negated conditional → KILLED
101		1.1 Location : decode Killed by : none replaced return value with "" for com/renomad/minum/utils/StringUtils::decode → TIMED_OUT
103		1.1 Location : decode Killed by : com.renomad.minum.web.BodyProcessorTests replaced return value with "" for com/renomad/minum/utils/StringUtils::decode → KILLED
112		1.1 Location : generateSecureRandomString Killed by : com.renomad.minum.utils.StringUtilsTests negated conditional → KILLED 2.2 Location : generateSecureRandomString Killed by : com.renomad.minum.utils.StringUtilsTests changed conditional boundary → KILLED
115		1.1 Location : generateSecureRandomString Killed by : com.renomad.minum.utils.StringUtilsTests changed conditional boundary → KILLED 2.2 Location : generateSecureRandomString Killed by : com.renomad.minum.utils.StringUtilsTests negated conditional → KILLED
121		1.1 Location : generateSecureRandomString Killed by : com.renomad.minum.utils.StringUtilsTests Replaced integer addition with subtraction → KILLED 2.2 Location : generateSecureRandomString Killed by : com.renomad.minum.utils.StringUtilsTests replaced return value with "" for com/renomad/minum/utils/StringUtils::generateSecureRandomString → KILLED
122		1.1 Location : lambda$generateSecureRandomString$0 Killed by : com.renomad.minum.FunctionalTests.testEndToEnd_Functional(com.renomad.minum.FunctionalTests) replaced Character return value with 0 for com/renomad/minum/utils/StringUtils::lambda$generateSecureRandomString$0 → KILLED
131		1.1 Location : byteListToString Killed by : com.renomad.minum.utils.StringUtilsTests negated conditional → KILLED 2.2 Location : byteListToString Killed by : com.renomad.minum.utils.StringUtilsTests replaced return value with "" for com/renomad/minum/utils/StringUtils::byteListToString → KILLED
134		1.1 Location : byteListToString Killed by : com.renomad.minum.utils.StringUtilsTests changed conditional boundary → KILLED 2.2 Location : byteListToString Killed by : com.renomad.minum.utils.StringUtilsTests negated conditional → KILLED
137		1.1 Location : byteListToString Killed by : com.renomad.minum.utils.StringUtilsTests replaced return value with "" for com/renomad/minum/utils/StringUtils::byteListToString → KILLED
144		1.1 Location : byteArrayToString Killed by : com.renomad.minum.utils.StringUtilsTests negated conditional → KILLED 2.2 Location : byteArrayToString Killed by : com.renomad.minum.utils.StringUtilsTests replaced return value with "" for com/renomad/minum/utils/StringUtils::byteArrayToString → KILLED
145		1.1 Location : byteArrayToString Killed by : com.renomad.minum.web.BodyProcessorTests replaced return value with "" for com/renomad/minum/utils/StringUtils::byteArrayToString → KILLED
156		1.1 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests negated conditional → KILLED 2.2 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests negated conditional → KILLED
157		1.1 Location : isPureDigits Killed by : com.renomad.minum.utils.StringUtilsTests replaced boolean return with true for com/renomad/minum/utils/StringUtils::isPureDigits → KILLED
159		1.1 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests changed conditional boundary → KILLED 2.2 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests negated conditional → KILLED
161		1.1 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests changed conditional boundary → KILLED 2.2 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests negated conditional → KILLED 3.3 Location : isPureDigits Killed by : com.renomad.minum.utils.StringUtilsTests changed conditional boundary → KILLED 4.4 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests negated conditional → KILLED
162		1.1 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests replaced boolean return with true for com/renomad/minum/utils/StringUtils::isPureDigits → KILLED
165		1.1 Location : isPureDigits Killed by : com.renomad.minum.web.HeadersTests replaced boolean return with false for com/renomad/minum/utils/StringUtils::isPureDigits → KILLED

StringUtils.java

Mutations

Active mutators

Tests examined