io.debezium.util

Class Strings

java.lang.Object

io.debezium.util.Strings

@ThreadSafe
public final class Strings
extends Object

String-related utility methods.

Author:

Randall Hauch, Horia Chiorean

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	Strings.CharacterPredicate Represents a predicate (boolean-valued function) of one character argument.
static class	Strings.Justify

Constructor Summary

Constructors

Modifier	Constructor and Description
private	Strings()

Method Summary

Modifier and Type	Method and Description
static boolean	asBoolean(String value, boolean defaultValue) Parse the supplied string as a boolean value.
static double	asDouble(String value, double defaultValue) Parse the supplied string as a double value.
static int	asInt(String value, int defaultValue) Parse the supplied string as a integer value.
static long	asLong(String value, long defaultValue) Parse the supplied string as a long value.
static int	compareTo(CharSequence str1, CharSequence str2) Compare two CharSequence instances.
static String	createString(char charToRepeat, int numberOfRepeats) Create a new string containing the specified character repeated a specific number of times.
static String	duration(long durationInMillis) For the given duration in milliseconds, obtain a readable representation of the form HHH:MM:SS.mmm, where HHH is the number of hours written in at least 2 digits (e.g., "03") MM is the number of hours written in at least 2 digits (e.g., "05") SS is the number of hours written in at least 2 digits (e.g., "09") mmm is the fractional part of seconds, written with 1-3 digits (any trailing zeros are dropped)
static String	getStackTrace(Throwable throwable) Get the stack trace of the supplied exception.
static String	join(CharSequence delimiter, int[] values) Returns a new String composed of the supplied integer values joined together with a copy of the specified delimiter.
static String	justify(Strings.Justify justify, String str, int width, char padWithChar) Justify the contents of the string.
static String	justifyCenter(String str, int width, char padWithChar) Center the contents of the string.
static String	justifyLeft(String str, int width, char padWithChar) Left justify the contents of the string, ensuring that the supplied string begins at the first character and that the resulting string is of the desired length.
protected static String	justifyLeft(String str, int width, char padWithChar, boolean trimWhitespace)
static String	justifyRight(String str, int width, char padWithChar) Right justify the contents of the string, ensuring that the string ends at the last character.
static <T> Set<T>	listOf(String input, char delimiter, Function<String,T> factory) Generate the set of values that are included in the list delimited by the given delimiter.
static <T> Set<T>	listOf(String input, Function<String,String[]> splitter, Function<String,T> factory) Generate the set of values that are included in the list.
static <T> Set<T>	listOf(String input, Function<String,T> factory) Generate the set of values that are included in the list separated by commas.
static Set<Pattern>	listOfRegex(String input) Generate the set of regular expression Patterns that are specified in the string containing comma-separated regular expressions.
static Set<Pattern>	listOfRegex(String input, int regexFlags) Generate the set of regular expression Patterns that are specified in the string containing comma-separated regular expressions.
static String	setLength(String original, int length, char padChar) Set the length of the string, padding with the supplied character if the supplied string is shorter than desired, or truncating the string if it is longer than desired.
static List<String>	splitLines(String content) Split the supplied content into lines, returning each line as an element in the returned list.
static String	trim(String str) Trim away any leading or trailing whitespace characters.
static String	trim(String str, Strings.CharacterPredicate predicate) Trim away any leading or trailing characters that satisfy the supplied predicate

Methods inherited from class java.lang.Object

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

Constructor Detail

Strings

private Strings()

Method Detail

listOf

public static <T> Set<T> listOf(String input,
                                Function<String,String[]> splitter,
                                Function<String,T> factory)

Generate the set of values that are included in the list.

Parameters:

input - the input string

splitter - the function that splits the input into multiple items; may not be null

factory - the factory for creating string items into filter matches; may not be null

Returns:

the list of objects included in the list; never null

listOf

public static <T> Set<T> listOf(String input,
                                char delimiter,
                                Function<String,T> factory)

Generate the set of values that are included in the list delimited by the given delimiter.

Parameters:

input - the input string

delimiter - the character used to delimit the items in the input

factory - the factory for creating string items into filter matches; may not be null

Returns:

the list of objects included in the list; never null

listOf

public static <T> Set<T> listOf(String input,
                                Function<String,T> factory)

Generate the set of values that are included in the list separated by commas.

Parameters:

input - the input string

factory - the factory for creating string items into filter matches; may not be null

Returns:

the list of objects included in the list; never null

listOfRegex

public static Set<Pattern> listOfRegex(String input)

Generate the set of regular expression Patterns that are specified in the string containing comma-separated regular expressions.

Parameters:

input - the input string with comma-separated regular expressions

Returns:

the list of regular expression Patterns included in the list; never null

listOfRegex

public static Set<Pattern> listOfRegex(String input,
                                       int regexFlags)

Generate the set of regular expression Patterns that are specified in the string containing comma-separated regular expressions.

Parameters:

input - the input string with comma-separated regular expressions

regexFlags - the flags for compiling regular expressions

Returns:

the list of regular expression Patterns included in the list; never null

splitLines

public static List<String> splitLines(String content)

Split the supplied content into lines, returning each line as an element in the returned list.

Parameters:

content - the string content that is to be split

Returns:

the list of lines; never null but may be an empty (unmodifiable) list if the supplied content is null or empty

compareTo

public static int compareTo(CharSequence str1,
                            CharSequence str2)

Compare two CharSequence instances.

Parameters:

str1 - the first character sequence; may be null

str2 - the second character sequence; may be null

Returns:

a negative integer if the first sequence is less than the second, zero if the sequence are equivalent (including if both are null), or a positive integer if the first sequence is greater than the second

join

public static String join(CharSequence delimiter,
                          int[] values)

Returns a new String composed of the supplied integer values joined together with a copy of the specified delimiter.

Parameters:

delimiter - the delimiter that separates each element

values - the values 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

See Also:

String.join(java.lang.CharSequence, java.lang.CharSequence...)

trim

public static String trim(String str)

Trim away any leading or trailing whitespace characters.

This is semantically equivalent to String.trim() but instead uses trim(String, CharacterPredicate).

Parameters:

str - the string to be trimmed; may not be null

Returns:

the trimmed string; never null

See Also:

trim(String,CharacterPredicate)

trim

public static String trim(String str,
                          Strings.CharacterPredicate predicate)

Trim away any leading or trailing characters that satisfy the supplied predicate

Parameters:

str - the string to be trimmed; may not be null

predicate - the predicate function; may not be null

Returns:

the trimmed string; never null

See Also:

trim(String)

createString

public static String createString(char charToRepeat,
                                  int numberOfRepeats)

Create a new string containing the specified character repeated a specific number of times.

Parameters:

charToRepeat - the character to repeat

numberOfRepeats - the number of times the character is to repeat in the result; must be greater than 0

Returns:

the resulting string

setLength

public static String setLength(String original,
                               int length,
                               char padChar)

Set the length of the string, padding with the supplied character if the supplied string is shorter than desired, or truncating the string if it is longer than desired. Unlike justifyLeft(String, int, char), this method does not remove leading and trailing whitespace.

Parameters:

original - the string for which the length is to be set; may not be null

length - the desired length; must be positive

padChar - the character to use for padding, if the supplied string is not long enough

Returns:

the string of the desired length

See Also:

justifyLeft(String, int, char)

justify

public static String justify(Strings.Justify justify,
                             String str,
                             int width,
                             char padWithChar)

Justify the contents of the string.

Parameters:

justify - the way in which the string is to be justified

str - the string to be right justified; if null, an empty string is used

width - the desired width of the string; must be positive

padWithChar - the character to use for padding, if needed

Returns:

the right justified string

justifyRight

public static String justifyRight(String str,
                                  int width,
                                  char padWithChar)

Right justify the contents of the string, ensuring that the string ends at the last character. If the supplied string is longer than the desired width, the leading characters are removed so that the last character in the supplied string at the last position. If the supplied string is shorter than the desired width, the padding character is inserted one or more times such that the last character in the supplied string appears as the last character in the resulting string and that the length matches that specified.

Parameters:

str - the string to be right justified; if null, an empty string is used

width - the desired width of the string; must be positive

padWithChar - the character to use for padding, if needed

Returns:

the right justified string

justifyLeft

public static String justifyLeft(String str,
                                 int width,
                                 char padWithChar)

Left justify the contents of the string, ensuring that the supplied string begins at the first character and that the resulting string is of the desired length. If the supplied string is longer than the desired width, it is truncated to the specified length. If the supplied string is shorter than the desired width, the padding character is added to the end of the string one or more times such that the length is that specified. All leading and trailing whitespace is removed.

Parameters:

str - the string to be left justified; if null, an empty string is used

width - the desired width of the string; must be positive

padWithChar - the character to use for padding, if needed

Returns:

the left justified string

See Also:

setLength(String, int, char)

justifyLeft

protected static String justifyLeft(String str,
                                    int width,
                                    char padWithChar,
                                    boolean trimWhitespace)

justifyCenter

public static String justifyCenter(String str,
                                   int width,
                                   char padWithChar)

Center the contents of the string. If the supplied string is longer than the desired width, it is truncated to the specified length. If the supplied string is shorter than the desired width, padding characters are added to the beginning and end of the string such that the length is that specified; one additional padding character is prepended if required. All leading and trailing whitespace is removed before centering.

Parameters:

str - the string to be left justified; if null, an empty string is used

width - the desired width of the string; must be positive

padWithChar - the character to use for padding, if needed

Returns:

the left justified string

See Also:

setLength(String, int, char)

getStackTrace

public static String getStackTrace(Throwable throwable)

Get the stack trace of the supplied exception.

Parameters:

throwable - the exception for which the stack trace is to be returned

Returns:

the stack trace, or null if the supplied exception is null

asInt

public static int asInt(String value,
                        int defaultValue)

Parse the supplied string as a integer value.

Parameters:

value - the string representation of a integer value

defaultValue - the value to return if the string value is null or cannot be parsed as an int

Returns:

the int value

asLong

public static long asLong(String value,
                          long defaultValue)

Parse the supplied string as a long value.

Parameters:

value - the string representation of a long value

defaultValue - the value to return if the string value is null or cannot be parsed as a long

Returns:

the long value

asDouble

public static double asDouble(String value,
                              double defaultValue)

Parse the supplied string as a double value.

Parameters:

value - the string representation of a double value

defaultValue - the value to return if the string value is null or cannot be parsed as a double

Returns:

the double value

asBoolean

public static boolean asBoolean(String value,
                                boolean defaultValue)

Parse the supplied string as a boolean value.

Parameters:

value - the string representation of a boolean value

defaultValue - the value to return if the string value is null or cannot be parsed as a boolean

Returns:

the boolean value

duration

public static String duration(long durationInMillis)

For the given duration in milliseconds, obtain a readable representation of the form HHH:MM:SS.mmm, where

HHH

is the number of hours written in at least 2 digits (e.g., "03")

MM

is the number of hours written in at least 2 digits (e.g., "05")

SS

is the number of hours written in at least 2 digits (e.g., "09")

mmm

is the fractional part of seconds, written with 1-3 digits (any trailing zeros are dropped)

Parameters:

durationInMillis - the duration in milliseconds

Returns:

the readable duration.