Class Utility

java.lang.Object

org.graalvm.shadowed.com.ibm.icu.impl.Utility

public final class Utility
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
static String	LINE_SEPARATOR

Constructor Summary

Constructors

Constructor	Description
Utility()

Method Summary

Modifier and Type	Method	Description
static int	addExact(int x, int y)	This implementation is equivalent to Java 8+ Math#addExact(int, int)
static <T extends Appendable> T	appendNumber(T result, int n, int radix, int minDigits)	Append a number to the given Appendable in the given radix.
static <A extends Appendable> A	appendTo(CharSequence string, A appendable)	Appends a CharSequence to an Appendable, converting IOException to ICUUncheckedIOException.
static void	appendToRule(StringBuffer rule, int c, boolean isLiteral, boolean escapeUnprintable, StringBuffer quoteBuf)	Append a character to a rule that is being built up.
static void	appendToRule(StringBuffer rule, String text, boolean isLiteral, boolean escapeUnprintable, StringBuffer quoteBuf)	Append the given string to the rule.
static void	appendToRule(StringBuffer rule, UnicodeMatcher matcher, boolean escapeUnprintable, StringBuffer quoteBuf)	Given a matcher reference, which may be null, append its pattern as a literal to the given rule.
static final boolean	arrayEquals(byte[] source, Object target)
static final boolean	arrayEquals(double[] source, Object target)	Convenience utility to compare two double[]s Ought to be in System
static final boolean	arrayEquals(int[] source, Object target)	Convenience utility to compare two int[]s Ought to be in System
static final boolean	arrayEquals(Object[] source, Object target)	Convenience utility to compare two Object[]s.
static final boolean	arrayEquals(Object source, Object target)	Convenience utility to compare two Object[]s Ought to be in System
static final boolean	arrayRegionMatches(byte[] source, int sourceStart, byte[] target, int targetStart, int len)
static final boolean	arrayRegionMatches(char[] source, int sourceStart, char[] target, int targetStart, int len)	Convenience utility to compare two Object[]s Ought to be in System.
static final boolean	arrayRegionMatches(double[] source, int sourceStart, double[] target, int targetStart, int len)	Convenience utility to compare two arrays of doubles.
static final boolean	arrayRegionMatches(int[] source, int sourceStart, int[] target, int targetStart, int len)	Convenience utility to compare two int[]s.
static final boolean	arrayRegionMatches(Object[] source, int sourceStart, Object[] target, int targetStart, int len)	Convenience utility to compare two Object[]s Ought to be in System.
static final String	arrayToRLEString(byte[] a)	Construct a string representing a byte array.
static final String	arrayToRLEString(char[] a)	Construct a string representing a char array.
static final String	arrayToRLEString(int[] a)	Construct a string representing an int array.
static final String	arrayToRLEString(short[] a)	Construct a string representing a short array.
static boolean	charSequenceEquals(CharSequence a, CharSequence b)	Returns whether the chars in the two CharSequences are equal.
static int	charSequenceHashCode(CharSequence value)	Returns a hash code for a CharSequence that is equivalent to calling charSequence.toString().hashCode()
static <T extends Comparable<T>> int	checkCompare(T a, T b)	Convenience utility.
static int	checkHash(Object a)	Convenience utility.
static final int	compareUnsigned(int source, int target)	Compares 2 unsigned integers
static int	cpFromCodePointAndLength(int cpAndLength)
static final String	escape(String s)	Convert characters outside the range U+0020 to U+007F to Unicode escapes, and convert backslash to a double backslash.
static <T extends Appendable> T	escape(T result, int c)	Escapes one code point using uxxxx notation for U+0000 to U+FFFF and Uxxxxxxxx for U+10000 and above.
static <T extends Appendable> boolean	escapeUnprintable(T result, int c)	Escapes one unprintable code point using uxxxx notation for U+0000 to U+FFFF and Uxxxxxxxx for U+10000 and above.
static final String	format1ForSource(String s)	Format a String for representation in a source file.
static final String	formatForSource(String s)	Format a String for representation in a source file.
static String	fromHex(String string, int minLength, String separator)	Parse a list of hex numbers and return a string
static String	fromHex(String string, int minLength, Pattern separator)	Parse a list of hex numbers and return a string
static String	hex(byte[] o, int start, int end, String separator)
static String	hex(long ch)	Convert a char to 4 hex uppercase digits.
static String	hex(long i, int places)	Supplies a zero-padded hex representation of an integer (without 0x)
static String	hex(CharSequence s)	Convert a string to comma-separated groups of 4 hex uppercase digits.
static <S extends CharSequence> String	hex(S s, int width, S separator)	Convert a string to comma-separated groups of 4 hex uppercase digits.
static <S extends CharSequence, U extends CharSequence, T extends Appendable> T	hex(S s, int width, U separator, boolean useCodePoints, T result)	Convert a string to separated groups of hex uppercase digits.
static final byte	highBit(int n)	Find the highest bit in a positive integer.
static boolean	isUnprintable(int c)	Return true if the character is NOT printable ASCII.
static String	joinStrings(CharSequence delimiter, Iterable<? extends CharSequence> elements)	Java 8+ String#join(CharSequence, Iterableinvalid input: '<'? extends CharSequence>) compatible method for Java 7 env.
static int	lengthFromCodePointAndLength(int cpAndLength)
static int	lookup(String source, String[] target)	Look up a given string in a string array.
static boolean	parseChar(String id, int[] pos, char ch)	Parse a single non-whitespace character 'ch', optionally preceded by whitespace.
static int	parseInteger(String rule, int[] pos, int limit)	Parse an integer at pos, either of the form \d+ or of the form 0x[0-9A-Fa-f]+ or 0[0-7]+, that is, in standard decimal, hex, or octal format.
static int	parseNumber(String text, int[] pos, int radix)	Parse an unsigned 31-bit integer at the given offset.
static int	parsePattern(String rule, int pos, int limit, String pattern, int[] parsedInts)	Parse a pattern string starting at offset pos.
static int	parsePattern(String pat, Replaceable text, int index, int limit)	Parse a pattern string within the given Replaceable and a parsing pattern.
static String	parseUnicodeIdentifier(String str, int[] pos)	Parse a Unicode identifier from the given string at the given position.
static int	quotedIndexOf(String text, int start, int limit, String setOfChars)	Returns the index of the first character in a set, ignoring quoted text.
static String	repeat(String s, int count)	Utility to duplicate a string count times
static final byte[]	RLEStringToByteArray(String s)	Construct an array of bytes from a run-length encoded string.
static final char[]	RLEStringToCharArray(String s)	Construct an array of shorts from a run-length encoded string.
static final int[]	RLEStringToIntArray(String s)	Construct an array of ints from a run-length encoded string.
static final short[]	RLEStringToShortArray(String s)	Construct an array of shorts from a run-length encoded string.
static final boolean	sameObjects(Object a, Object b)	Trivial reference equality.
static boolean	shouldAlwaysBeEscaped(int c)
static String[]	split(String s, char divider)	Split a string into pieces based on the given divider character
static void	split(String s, char divider, String[] output)	Split a string into pieces based on the given divider character
static String[]	splitString(String src, String target)
static String[]	splitWhitespace(String src)	Split the string at runs of ascii whitespace characters.
static String	unescape(CharSequence s)	Convert all escapes in a given string using unescapeAndLengthAt().
static int	unescapeAndLengthAt(CharSequence s, int offset)	Converts an escape to a code point value.
static String	unescapeLeniently(CharSequence s)	Convert all escapes in a given string using unescapeAndLengthAt().
static String	valueOf(int[] source)	Utility method to take a int[] containing codepoints and return a string representation with code units.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

LINE_SEPARATOR

public static String LINE_SEPARATOR

Constructor Details

Utility

public Utility()

Method Details

arrayEquals

public static final boolean arrayEquals(Object[] source,
 Object target)

Convenience utility to compare two Object[]s. Ought to be in System

arrayEquals

public static final boolean arrayEquals(int[] source,
 Object target)

Convenience utility to compare two int[]s Ought to be in System

arrayEquals

public static final boolean arrayEquals(double[] source,
 Object target)

Convenience utility to compare two double[]s Ought to be in System

arrayEquals

public static final boolean arrayEquals(byte[] source,
 Object target)

arrayEquals

public static final boolean arrayEquals(Object source,
 Object target)

Convenience utility to compare two Object[]s Ought to be in System

arrayRegionMatches

public static final boolean arrayRegionMatches(Object[] source,
 int sourceStart,
 Object[] target,
 int targetStart,
 int len)

Convenience utility to compare two Object[]s Ought to be in System.

Parameters:

len - the length to compare. The start indices and start+len must be valid.

arrayRegionMatches

public static final boolean arrayRegionMatches(char[] source,
 int sourceStart,
 char[] target,
 int targetStart,
 int len)

Convenience utility to compare two Object[]s Ought to be in System.

Parameters:

len - the length to compare. The start indices and start+len must be valid.

arrayRegionMatches

public static final boolean arrayRegionMatches(int[] source,
 int sourceStart,
 int[] target,
 int targetStart,
 int len)

Convenience utility to compare two int[]s.

Parameters:

len - the length to compare. The start indices and start+len must be valid. Ought to be in System

arrayRegionMatches

public static final boolean arrayRegionMatches(double[] source,
 int sourceStart,
 double[] target,
 int targetStart,
 int len)

Convenience utility to compare two arrays of doubles.

Parameters:

len - the length to compare. The start indices and start+len must be valid. Ought to be in System

arrayRegionMatches

public static final boolean arrayRegionMatches(byte[] source,
 int sourceStart,
 byte[] target,
 int targetStart,
 int len)

sameObjects

public static final boolean sameObjects(Object a,
 Object b)

Trivial reference equality. This method should help document that we really want == not equals(), and to have a single place to suppress warnings from static analysis tools.

checkCompare

public static <T extends Comparable<T>> int checkCompare(T a,
 T b)

Convenience utility. Does null checks on objects, then calls compare.

checkHash

public static int checkHash(Object a)

Convenience utility. Does null checks on object, then calls hashCode.

arrayToRLEString

public static final String arrayToRLEString(int[] a)

Construct a string representing an int array. Use run-length encoding. A character represents itself, unless it is the ESCAPE character. Then the following notations are possible: ESCAPE ESCAPE ESCAPE literal ESCAPE n c n instances of character c Since an encoded run occupies 3 characters, we only encode runs of 4 or more characters. Thus we have n > 0 and n != ESCAPE and n invalid input: '<'= 0xFFFF. If we encounter a run where n == ESCAPE, we represent this as: c ESCAPE n-1 c The ESCAPE value is chosen so as not to collide with commonly seen values.

arrayToRLEString

public static final String arrayToRLEString(short[] a)

Construct a string representing a short array. Use run-length encoding. A character represents itself, unless it is the ESCAPE character. Then the following notations are possible: ESCAPE ESCAPE ESCAPE literal ESCAPE n c n instances of character c Since an encoded run occupies 3 characters, we only encode runs of 4 or more characters. Thus we have n > 0 and n != ESCAPE and n invalid input: '<'= 0xFFFF. If we encounter a run where n == ESCAPE, we represent this as: c ESCAPE n-1 c The ESCAPE value is chosen so as not to collide with commonly seen values.

arrayToRLEString

public static final String arrayToRLEString(char[] a)

Construct a string representing a char array. Use run-length encoding. A character represents itself, unless it is the ESCAPE character. Then the following notations are possible: ESCAPE ESCAPE ESCAPE literal ESCAPE n c n instances of character c Since an encoded run occupies 3 characters, we only encode runs of 4 or more characters. Thus we have n > 0 and n != ESCAPE and n invalid input: '<'= 0xFFFF. If we encounter a run where n == ESCAPE, we represent this as: c ESCAPE n-1 c The ESCAPE value is chosen so as not to collide with commonly seen values.

arrayToRLEString

public static final String arrayToRLEString(byte[] a)

Construct a string representing a byte array. Use run-length encoding. Two bytes are packed into a single char, with a single extra zero byte at the end if needed. A byte represents itself, unless it is the ESCAPE_BYTE. Then the following notations are possible: ESCAPE_BYTE ESCAPE_BYTE ESCAPE_BYTE literal ESCAPE_BYTE n b n instances of byte b Since an encoded run occupies 3 bytes, we only encode runs of 4 or more bytes. Thus we have n > 0 and n != ESCAPE_BYTE and n invalid input: '<'= 0xFF. If we encounter a run where n == ESCAPE_BYTE, we represent this as: b ESCAPE_BYTE n-1 b The ESCAPE_BYTE value is chosen so as not to collide with commonly seen values.

RLEStringToIntArray

public static final int[] RLEStringToIntArray(String s)

Construct an array of ints from a run-length encoded string.

RLEStringToShortArray

public static final short[] RLEStringToShortArray(String s)

Construct an array of shorts from a run-length encoded string.

RLEStringToCharArray

public static final char[] RLEStringToCharArray(String s)

Construct an array of shorts from a run-length encoded string.

RLEStringToByteArray

public static final byte[] RLEStringToByteArray(String s)

Construct an array of bytes from a run-length encoded string.

formatForSource

public static final String formatForSource(String s)

Format a String for representation in a source file. This includes breaking it into lines and escaping characters using octal notation when necessary (control characters and double quotes).

format1ForSource

public static final String format1ForSource(String s)

Format a String for representation in a source file. Like formatForSource but does not do line breaking.

escape

public static final String escape(String s)

Convert characters outside the range U+0020 to U+007F to Unicode escapes, and convert backslash to a double backslash.

unescapeAndLengthAt

public static int unescapeAndLengthAt(CharSequence s,
 int offset)

Converts an escape to a code point value. We attempt to parallel the icu4c unescapeAt() function. This function returns an integer with both the code point (bits 28..8) and the length of the escape sequence (bits 7..0). offset+length is the index after the escape sequence.

Parameters:

offset - the offset to the character after the backslash.

Returns:

the code point and length, or -1 on error.

cpFromCodePointAndLength

public static int cpFromCodePointAndLength(int cpAndLength)

lengthFromCodePointAndLength

public static int lengthFromCodePointAndLength(int cpAndLength)

unescape

public static String unescape(CharSequence s)

Convert all escapes in a given string using unescapeAndLengthAt().

Throws:

IllegalArgumentException - if an invalid escape is seen.

unescapeLeniently

public static String unescapeLeniently(CharSequence s)

Convert all escapes in a given string using unescapeAndLengthAt(). Leave invalid escape sequences unchanged.

hex

public static String hex(long ch)

Convert a char to 4 hex uppercase digits. E.g., hex('a') => "0041".

hex

public static String hex(long i,
 int places)

Supplies a zero-padded hex representation of an integer (without 0x)

hex

public static String hex(CharSequence s)

Convert a string to comma-separated groups of 4 hex uppercase digits. E.g., hex('ab') => "0041,0042".

hex

public static <S extends CharSequence, U extends CharSequence, T extends Appendable>
T hex(S s,
 int width,
 U separator,
 boolean useCodePoints,
 T result)

Convert a string to separated groups of hex uppercase digits. E.g., hex('ab'...) => "0041,0042". Append the output to the given Appendable.

hex

public static String hex(byte[] o,
 int start,
 int end,
 String separator)

hex

public static <S extends CharSequence> String hex(S s,
 int width,
 S separator)

Convert a string to comma-separated groups of 4 hex uppercase digits. E.g., hex('ab') => "0041,0042".

split

public static void split(String s,
 char divider,
 String[] output)

Split a string into pieces based on the given divider character

Parameters:

s - the string to split

divider - the character on which to split. Occurrences of this character are not included in the output

output - an array to receive the substrings between instances of divider. It must be large enough on entry to accommodate all output. Adjacent instances of the divider character will place empty strings into output. Before returning, output is padded out with empty strings.

split

public static String[] split(String s,
 char divider)

Split a string into pieces based on the given divider character

Parameters:

s - the string to split

divider - the character on which to split. Occurrences of this character are not included in the output

Returns:

output an array to receive the substrings between instances of divider. Adjacent instances of the divider character will place empty strings into output.

lookup

public static int lookup(String source,
 String[] target)

Look up a given string in a string array. Returns the index at which the first occurrence of the string was found in the array, or -1 if it was not found.

Parameters:

source - the string to search for

target - the array of zero or more strings in which to look for source

Returns:

the index of target at which source first occurs, or -1 if not found

parseChar

public static boolean parseChar(String id,
 int[] pos,
 char ch)

Parse a single non-whitespace character 'ch', optionally preceded by whitespace.

Parameters:

id - the string to be parsed

pos - INPUT-OUTPUT parameter. On input, pos[0] is the offset of the first character to be parsed. On output, pos[0] is the index after the last parsed character. If the parse fails, pos[0] will be unchanged.

ch - the non-whitespace character to be parsed.

Returns:

true if 'ch' is seen preceded by zero or more whitespace characters.

parsePattern

public static int parsePattern(String rule,
 int pos,
 int limit,
 String pattern,
 int[] parsedInts)

Parse a pattern string starting at offset pos. Keywords are matched case-insensitively. Spaces may be skipped and may be optional or required. Integer values may be parsed, and if they are, they will be returned in the given array. If successful, the offset of the next non-space character is returned. On failure, -1 is returned.

Parameters:

pattern - must only contain lowercase characters, which will match their uppercase equivalents as well. A space character matches one or more required spaces. A '~' character matches zero or more optional spaces. A '#' character matches an integer and stores it in parsedInts, which the caller must ensure has enough capacity.

parsedInts - array to receive parsed integers. Caller must ensure that parsedInts.length is >= the number of '#' signs in 'pattern'.

Returns:

the position after the last character parsed, or -1 if the parse failed

parsePattern

public static int parsePattern(String pat,
 Replaceable text,
 int index,
 int limit)

Parse a pattern string within the given Replaceable and a parsing pattern. Characters are matched literally and case-sensitively except for the following special characters: ~ zero or more Pattern_White_Space chars If end of pattern is reached with all matches along the way, pos is advanced to the first unparsed index and returned. Otherwise -1 is returned.

Parameters:

pat - pattern that controls parsing

text - text to be parsed, starting at index

index - offset to first character to parse

limit - offset after last character to parse

Returns:

index after last parsed character, or -1 on parse failure.

parseInteger

public static int parseInteger(String rule,
 int[] pos,
 int limit)

Parse an integer at pos, either of the form \d+ or of the form 0x[0-9A-Fa-f]+ or 0[0-7]+, that is, in standard decimal, hex, or octal format.

Parameters:

pos - INPUT-OUTPUT parameter. On input, the first character to parse. On output, the character after the last parsed character.

parseUnicodeIdentifier

public static String parseUnicodeIdentifier(String str,
 int[] pos)

Parse a Unicode identifier from the given string at the given position. Return the identifier, or null if there is no identifier.

Parameters:

str - the string to parse

pos - INPUT-OUTPUT parameter. On INPUT, pos[0] is the first character to examine. It must be less than str.length(), and it must not point to a whitespace character. That is, must have pos[0] invalid input: '<' str.length(). On OUTPUT, the position after the last parsed character.

Returns:

the Unicode identifier, or null if there is no valid identifier at pos[0].

appendNumber

public static <T extends Appendable> T appendNumber(T result,
 int n,
 int radix,
 int minDigits)

Append a number to the given Appendable in the given radix. Standard digits '0'-'9' are used and letters 'A'-'Z' for radices 11 through 36.

Parameters:

result - the digits of the number are appended here

n - the number to be converted to digits; may be negative. If negative, a '-' is prepended to the digits.

radix - a radix from 2 to 36 inclusive.

minDigits - the minimum number of digits, not including any '-', to produce. Values less than 2 have no effect. One digit is always emitted regardless of this parameter.

Returns:

a reference to result

parseNumber

public static int parseNumber(String text,
 int[] pos,
 int radix)

Parse an unsigned 31-bit integer at the given offset. Use UCharacter.digit() to parse individual characters into digits.

Parameters:

text - the text to be parsed

pos - INPUT-OUTPUT parameter. On entry, pos[0] is the offset within text at which to start parsing; it should point to a valid digit. On exit, pos[0] is the offset after the last parsed character. If the parse failed, it will be unchanged on exit. Must be >= 0 on entry.

radix - the radix in which to parse; must be >= 2 and invalid input: '<'= 36.

Returns:

a non-negative parsed number, or -1 upon parse failure. Parse fails if there are no digits, that is, if pos[0] does not point to a valid digit on entry, or if the number to be parsed does not fit into a 31-bit unsigned integer.

isUnprintable

public static boolean isUnprintable(int c)

Return true if the character is NOT printable ASCII. The tab, newline and linefeed characters are considered unprintable.

shouldAlwaysBeEscaped

public static boolean shouldAlwaysBeEscaped(int c)

Returns:

true for control codes and for surrogate and noncharacter code points

escapeUnprintable

public static <T extends Appendable> boolean escapeUnprintable(T result,
 int c)

Escapes one unprintable code point using uxxxx notation for U+0000 to U+FFFF and Uxxxxxxxx for U+10000 and above. If the character is printable ASCII, then do nothing and return false. Otherwise, append the escaped notation and return true.

escape

public static <T extends Appendable> T escape(T result,
 int c)

Escapes one code point using uxxxx notation for U+0000 to U+FFFF and Uxxxxxxxx for U+10000 and above.

Returns:

result

quotedIndexOf

public static int quotedIndexOf(String text,
 int start,
 int limit,
 String setOfChars)

Returns the index of the first character in a set, ignoring quoted text. For example, in the string "abc'hide'h", the 'h' in "hide" will not be found by a search for "h". Unlike String.indexOf(), this method searches not for a single character, but for any character of the string setOfChars.

Parameters:

text - text to be searched

start - the beginning index, inclusive; 0 invalid input: '<'= start invalid input: '<'= limit.

limit - the ending index, exclusive; start invalid input: '<'= limit invalid input: '<'= text.length().

setOfChars - string with one or more distinct characters

Returns:

Offset of the first character in setOfChars found, or -1 if not found.

See Also:

• String.indexOf(int)

appendToRule

public static void appendToRule(StringBuffer rule,
 int c,
 boolean isLiteral,
 boolean escapeUnprintable,
 StringBuffer quoteBuf)

Append a character to a rule that is being built up. To flush the quoteBuf to rule, make one final call with isLiteral == true. If there is no final character, pass in (int)-1 as c.

Parameters:

rule - the string to append the character to

c - the character to append, or (int)-1 if none.

isLiteral - if true, then the given character should not be quoted or escaped. Usually this means it is a syntactic element such as > or $

escapeUnprintable - if true, then unprintable characters should be escaped using escapeUnprintable(). These escapes will appear outside of quotes.

quoteBuf - a buffer which is used to build up quoted substrings. The caller should initially supply an empty buffer, and thereafter should not modify the buffer. The buffer should be cleared out by, at the end, calling this method with a literal character (which may be -1).

appendToRule

public static void appendToRule(StringBuffer rule,
 String text,
 boolean isLiteral,
 boolean escapeUnprintable,
 StringBuffer quoteBuf)

Append the given string to the rule. Calls the single-character version of appendToRule for each character.

appendToRule

public static void appendToRule(StringBuffer rule,
 UnicodeMatcher matcher,
 boolean escapeUnprintable,
 StringBuffer quoteBuf)

Given a matcher reference, which may be null, append its pattern as a literal to the given rule.

compareUnsigned

public static final int compareUnsigned(int source,
 int target)

Compares 2 unsigned integers

Parameters:

source - 32 bit unsigned integer

target - 32 bit unsigned integer

Returns:

0 if equals, 1 if source is greater than target and -1 otherwise

highBit

public static final byte highBit(int n)

Find the highest bit in a positive integer. This is done by doing a binary search through the bits.

Parameters:

n - is the integer

Returns:

the bit number of the highest bit, with 0 being the low order bit, or -1 if n is not positive

valueOf

public static String valueOf(int[] source)

Utility method to take a int[] containing codepoints and return a string representation with code units.

repeat

public static String repeat(String s,
 int count)

Utility to duplicate a string count times

Parameters:

s - String to be duplicated.

count - Number of times to duplicate a string.

splitString

public static String[] splitString(String src,
 String target)

splitWhitespace

public static String[] splitWhitespace(String src)

Split the string at runs of ascii whitespace characters.

fromHex

public static String fromHex(String string,
 int minLength,
 String separator)

Parse a list of hex numbers and return a string

Parameters:

string - String of hex numbers.

minLength - Minimal length.

separator - Separator.

Returns:

A string from hex numbers.

fromHex

public static String fromHex(String string,
 int minLength,
 Pattern separator)

Parse a list of hex numbers and return a string

Parameters:

string - String of hex numbers.

minLength - Minimal length.

separator - Separator.

Returns:

A string from hex numbers.

addExact

public static int addExact(int x,
 int y)

This implementation is equivalent to Java 8+ Math#addExact(int, int)

Parameters:

x - the first value

y - the second value

Returns:

the result

charSequenceEquals

public static boolean charSequenceEquals(CharSequence a,
 CharSequence b)

Returns whether the chars in the two CharSequences are equal.

charSequenceHashCode

public static int charSequenceHashCode(CharSequence value)

Returns a hash code for a CharSequence that is equivalent to calling charSequence.toString().hashCode()

appendTo

public static <A extends Appendable> A appendTo(CharSequence string,
 A appendable)

Appends a CharSequence to an Appendable, converting IOException to ICUUncheckedIOException.

joinStrings

public static String joinStrings(CharSequence delimiter,
 Iterable<? extends CharSequence> elements)

Java 8+ String#join(CharSequence, Iterableinvalid input: '<'? extends CharSequence>) compatible method for Java 7 env.

Parameters:

delimiter - the delimiter that separates each element

elements - the elements to join together.

Returns:

a new String that is composed of the elements separated by the delimiter

Throws:

NullPointerException - If delimiter or elements is null