StringUtils (Smithy API 1.21.0)

java.lang.Object
- software.amazon.smithy.utils.StringUtils

```
public final class StringUtils
extends java.lang.Object
```
Operations on String that are null safe.
- IsEmpty/IsBlank - checks if a String contains text
- Trim - removes leading and trailing whitespace
- Equals/Compare - compares two strings null-safe
- Substring - null-safe substring extraction
- UpperCase/LowerCase/Capitalize/Uncapitalize - changes the case of a String
The StringUtils class defines certain words related to String handling.
- null - null
- empty - a zero-length string ("")
- space - the space character (' ', char 32)
- whitespace - the characters defined by Character.isWhitespace(char)
- trim - the characters <= 32 as in String.trim()
StringUtils handles null input Strings quietly. That is to say that a null input will return null. Where a boolean or int is being returned details vary by method.

A side effect of the null handling is that a NullPointerException should be considered a bug in StringUtils.

This class's source was modified from the Apache commons-lang and Apache commons-text libraries: https://github.com/apache/commons-lang/, https://github.com/apache/commons-text/

#ThreadSafe#
See Also:

String, Apache Commons Lang, Apache Commons Text , Elephant bird license

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static java.lang.String`	`capitalize(java.lang.String str)` Capitalizes a String changing the first character to title case as per `Character.toTitleCase(int)`.
`static boolean`	`equals(java.lang.String cs1, java.lang.String cs2)` Compares two Strings, returning `true` if they represent equal sequences of characters.
`static java.lang.String`	`escapeJavaString(java.lang.Object object, java.lang.String indent)`
`static boolean`	`isBlank(java.lang.CharSequence cs)` Checks if a CharSequence is empty (""), null or whitespace only.
`static boolean`	`isEmpty(java.lang.CharSequence cs)` Checks if a CharSequence is empty ("") or null.
`static boolean`	`isNotBlank(java.lang.CharSequence cs)` Checks if a CharSequence is not empty (""), not null and not whitespace only.
`static java.lang.String`	`leftPad(java.lang.String str, int size)` Left pad a String with spaces (' ').
`static java.lang.String`	`leftPad(java.lang.String str, int size, char padChar)` Left pad a String with a specified character.
`static java.lang.String`	`leftPad(java.lang.String str, int size, java.lang.String padStr)` Left pad a String with a specified String.
`static int`	`levenshteinDistance(java.lang.CharSequence left, java.lang.CharSequence right, int threshold)` Find the Levenshtein distance between two CharSequences if it's less than or equal to a given threshold.
`static java.lang.String`	`lowerCase(java.lang.String str)` Converts a String to lower case as per `String.toLowerCase()`.
`static java.lang.String`	`repeat(char ch, int repeat)` Returns padding using the specified delimiter repeated to a given length.
`static java.lang.String`	`repeat(java.lang.String str, int repeat)` Repeat a String `repeat` times to form a new String.
`static java.lang.String`	`rightPad(java.lang.String str, int size)` Right pad a String with spaces (' ').
`static java.lang.String`	`rightPad(java.lang.String str, int size, char padChar)` Right pad a String with a specified character.
`static java.lang.String`	`rightPad(java.lang.String str, int size, java.lang.String padStr)` Right pad a String with a specified String.
`static boolean`	`startsWithIgnoreCase(java.lang.String str, java.lang.String prefix)` Tests if this string starts with the specified prefix ignoring case considerations.
`static java.lang.String`	`strip(java.lang.String str, java.lang.String stripChars)` Strips any of a set of characters from the start and end of a String.
`static java.lang.String`	`stripEnd(java.lang.String str, java.lang.String stripChars)` Strips any of a set of characters from the end of a String.
`static java.lang.String`	`stripStart(java.lang.String str, java.lang.String stripChars)` Strips any of a set of characters from the start of a String.
`static java.lang.String`	`stripToEmpty(java.lang.String str)` Strips whitespace from the start and end of a String returning an empty String if `null` input.
`static java.lang.String`	`substring(java.lang.String str, int start)` Gets a substring from the specified String avoiding exceptions.
`static java.lang.String`	`substring(java.lang.String str, int start, int end)` Gets a substring from the specified String avoiding exceptions.
`static java.lang.String`	`trim(java.lang.String str)` Removes control characters (char <= 32) from both ends of this String, handling `null` by returning `null`.
`static java.lang.String`	`trimToEmpty(java.lang.String str)` Removes control characters (char <= 32) from both ends of this String returning an empty String ("") if the String is empty ("") after the trim or if it is `null`.
`static java.lang.String`	`trimToNull(java.lang.String str)` Removes control characters (char <= 32) from both ends of this String returning `null` if the String is empty ("") after the trim or if it is `null`.
`static java.lang.String`	`uncapitalize(java.lang.String str)` Uncapitalizes a String, changing the first character to lower case as per `Character.toLowerCase(int)`.
`static java.lang.String`	`upperCase(java.lang.String str)` Converts a String to upper case as per `String.toUpperCase()`.
`static java.lang.String`	`wrap(java.lang.String str, int wrapLength)` Wraps a single line of text, identifying words by `' '`.
`static java.lang.String`	`wrap(java.lang.String str, int wrapLength, java.lang.String newLineStr, boolean wrapLongWords)` Wraps a single line of text, identifying words by `' '`.
`static java.lang.String`	`wrap(java.lang.String str, int wrapLength, java.lang.String newLineStr, boolean wrapLongWords, java.lang.String wrapOn)` Wraps a single line of text, identifying words by `wrapOn`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

isEmpty
```
public static boolean isEmpty(java.lang.CharSequence cs)
```
Checks if a CharSequence is empty ("") or null.
```
 StringUtils.isEmpty(null)      = true
 StringUtils.isEmpty("")        = true
 StringUtils.isEmpty(" ")       = false
 StringUtils.isEmpty("bob")     = false
 StringUtils.isEmpty("  bob  ") = false
 
```
NOTE: This method changed in Lang version 2.0. It no longer trims the CharSequence. That functionality is available in isBlank().
Parameters:

cs - the CharSequence to check, may be null

Returns:

true if the CharSequence is empty or null

Since:

3.0 Changed signature from isEmpty(String) to isEmpty(CharSequence)

See Also:

Source

isBlank
```
public static boolean isBlank(java.lang.CharSequence cs)
```
Checks if a CharSequence is empty (""), null or whitespace only.

Whitespace is defined by Character.isWhitespace(char).
```
 StringUtils.isBlank(null)      = true
 StringUtils.isBlank("")        = true
 StringUtils.isBlank(" ")       = true
 StringUtils.isBlank("bob")     = false
 StringUtils.isBlank("  bob  ") = false
 
```
Parameters:

cs - the CharSequence to check, may be null

Returns:

true if the CharSequence is null, empty or whitespace only

Since:

2.0, 3.0 Changed signature from isBlank(String) to isBlank(CharSequence)

See Also:

Source

isNotBlank
```
public static boolean isNotBlank(java.lang.CharSequence cs)
```
Checks if a CharSequence is not empty (""), not null and not whitespace only.

Whitespace is defined by Character.isWhitespace(char).
```
 StringUtils.isNotBlank(null)      = false
 StringUtils.isNotBlank("")        = false
 StringUtils.isNotBlank(" ")       = false
 StringUtils.isNotBlank("bob")     = true
 StringUtils.isNotBlank("  bob  ") = true
 
```
Parameters:

cs - the CharSequence to check, may be null

Returns:

true if the CharSequence is not empty and not null and not whitespace only

Since:

2.0, 3.0 Changed signature from isNotBlank(String) to isNotBlank(CharSequence)

See Also:

Source

trim
```
public static java.lang.String trim(java.lang.String str)
```
Removes control characters (char <= 32) from both ends of this String, handling null by returning null.

The String is trimmed using String.trim(). Trim removes start and end characters <= 32.
```
 StringUtils.trim(null)          = null
 StringUtils.trim("")            = ""
 StringUtils.trim("     ")       = ""
 StringUtils.trim("abc")         = "abc"
 StringUtils.trim("    abc    ") = "abc"
 
```
Parameters:

str - the String to be trimmed, may be null

Returns:

the trimmed string, null if null String input

See Also:

Source

trimToNull
```
public static java.lang.String trimToNull(java.lang.String str)
```
Removes control characters (char <= 32) from both ends of this String returning null if the String is empty ("") after the trim or if it is null.
The String is trimmed using String.trim(). Trim removes start and end characters <= 32.
```
 StringUtils.trimToNull(null)          = null
 StringUtils.trimToNull("")            = null
 StringUtils.trimToNull("     ")       = null
 StringUtils.trimToNull("abc")         = "abc"
 StringUtils.trimToNull("    abc    ") = "abc"
 
```
Parameters:

str - the String to be trimmed, may be null

Returns:

the trimmed String, null if only chars <= 32, empty or null String input

Since:

2.0

See Also:

Source

trimToEmpty
```
public static java.lang.String trimToEmpty(java.lang.String str)
```
Removes control characters (char <= 32) from both ends of this String returning an empty String ("") if the String is empty ("") after the trim or if it is null.
The String is trimmed using String.trim(). Trim removes start and end characters <= 32.
```
 StringUtils.trimToEmpty(null)          = ""
 StringUtils.trimToEmpty("")            = ""
 StringUtils.trimToEmpty("     ")       = ""
 StringUtils.trimToEmpty("abc")         = "abc"
 StringUtils.trimToEmpty("    abc    ") = "abc"
 
```
Parameters:

str - the String to be trimmed, may be null

Returns:

the trimmed String, or an empty String if null input

Since:

2.0

See Also:

Source

equals
```
public static boolean equals(java.lang.String cs1,
                             java.lang.String cs2)
```
Compares two Strings, returning true if they represent equal sequences of characters.

nulls are handled without exceptions. Two null references are considered to be equal. The comparison is case sensitive.
```
 StringUtils.equals(null, null)   = true
 StringUtils.equals(null, "abc")  = false
 StringUtils.equals("abc", null)  = false
 StringUtils.equals("abc", "abc") = true
 StringUtils.equals("abc", "ABC") = false
 
```
Parameters:

cs1 - the first String, may be null

cs2 - the second String, may be null

Returns:

true if the Strings are equal (case-sensitive), or both null

See Also:

Object.equals(Object), Source

substring
```
public static java.lang.String substring(java.lang.String str,
                                         int start)
```
Gets a substring from the specified String avoiding exceptions.

A negative start position can be used to start n characters from the end of the String.

A null String will return null. An empty ("") String will return "".
```
 StringUtils.substring(null, *)   = null
 StringUtils.substring("", *)     = ""
 StringUtils.substring("abc", 0)  = "abc"
 StringUtils.substring("abc", 2)  = "c"
 StringUtils.substring("abc", 4)  = ""
 StringUtils.substring("abc", -2) = "bc"
 StringUtils.substring("abc", -4) = "abc"
 
```
Parameters:

str - the String to get the substring from, may be null

start - the position to start from, negative means count back from the end of the String by this many characters

Returns:

substring from start position, null if null String input

See Also:

Source

substring
```
public static java.lang.String substring(java.lang.String str,
                                         int start,
                                         int end)
```
Gets a substring from the specified String avoiding exceptions.

A negative start position can be used to start/end n characters from the end of the String.

The returned substring starts with the character in the start position and ends before the end position. All position counting is zero-based -- i.e., to start at the beginning of the string use start = 0. Negative start and end positions can be used to specify offsets relative to the end of the String.

If start is not strictly to the left of end, "" is returned.
```
 StringUtils.substring(null, *, *)    = null
 StringUtils.substring("", * ,  *)    = "";
 StringUtils.substring("abc", 0, 2)   = "ab"
 StringUtils.substring("abc", 2, 0)   = ""
 StringUtils.substring("abc", 2, 4)   = "c"
 StringUtils.substring("abc", 4, 6)   = ""
 StringUtils.substring("abc", 2, 2)   = ""
 StringUtils.substring("abc", -2, -1) = "b"
 StringUtils.substring("abc", -4, 2)  = "ab"
 
```
Parameters:

str - the String to get the substring from, may be null

start - the position to start from, negative means count back from the end of the String by this many characters

end - the position to end at (exclusive), negative means count back from the end of the String by this many scharacters

Returns:

substring from start position to end position, null if null String input

See Also:

Source

upperCase
```
public static java.lang.String upperCase(java.lang.String str)
```
Converts a String to upper case as per String.toUpperCase().

A null input String returns null.
```
 StringUtils.upperCase(null)  = null
 StringUtils.upperCase("")    = ""
 StringUtils.upperCase("aBc") = "ABC"
 
```
This uses "ENGLISH" as the locale.
Parameters:

str - the String to upper case, may be null

Returns:

the upper cased String, null if null String input

See Also:

Source

lowerCase
```
public static java.lang.String lowerCase(java.lang.String str)
```
Converts a String to lower case as per String.toLowerCase().

A null input String returns null.
```
 StringUtils.lowerCase(null)  = null
 StringUtils.lowerCase("")    = ""
 StringUtils.lowerCase("aBc") = "abc"
 
```
This uses "ENGLISH" as the locale.
Parameters:

str - the String to lower case, may be null

Returns:

the lower cased String, null if null String input

See Also:

Source

capitalize
```
public static java.lang.String capitalize(java.lang.String str)
```
Capitalizes a String changing the first character to title case as per Character.toTitleCase(int). No other characters are changed.
```
 StringUtils.capitalize(null)  = null
 StringUtils.capitalize("")    = ""
 StringUtils.capitalize("cat") = "Cat"
 StringUtils.capitalize("cAt") = "CAt"
 StringUtils.capitalize("'cat'") = "'cat'"
 
```
Parameters:

str - the String to capitalize, may be null

Returns:

the capitalized String, null if null String input

Since:

2.0

See Also:

uncapitalize(String), Source

uncapitalize
```
public static java.lang.String uncapitalize(java.lang.String str)
```
Uncapitalizes a String, changing the first character to lower case as per Character.toLowerCase(int). No other characters are changed.
```
 StringUtils.uncapitalize(null)  = null
 StringUtils.uncapitalize("")    = ""
 StringUtils.uncapitalize("cat") = "cat"
 StringUtils.uncapitalize("Cat") = "cat"
 StringUtils.uncapitalize("CAT") = "cAT"
 
```
Parameters:

str - the String to uncapitalize, may be null

Returns:

the uncapitalized String, null if null String input

Since:

2.0

See Also:

capitalize(String), Source

startsWithIgnoreCase
```
public static boolean startsWithIgnoreCase(java.lang.String str,
                                           java.lang.String prefix)
```
Tests if this string starts with the specified prefix ignoring case considerations.

Parameters:

str - the string to be tested

prefix - the prefix

Returns:

true if the string starts with the prefix ignoring case

repeat

public static java.lang.String repeat(java.lang.String str,
                                      int repeat)

Repeat a String repeat times to form a new String.

 StringUtils.repeat(null, 2) = null
 StringUtils.repeat("", 0)   = ""
 StringUtils.repeat("", 2)   = ""
 StringUtils.repeat("a", 3)  = "aaa"
 StringUtils.repeat("ab", 2) = "abab"
 StringUtils.repeat("a", -2) = ""

Parameters:: str - the String to repeat, may be null; repeat - number of times to repeat str, negative treated as zero
Returns:: a new String consisting of the original String repeated, null if null String input
See Also:: Source

repeat
```
public static java.lang.String repeat(char ch,
                                      int repeat)
```
Returns padding using the specified delimiter repeated to a given length.
```
 StringUtils.repeat('e', 0)  = ""
 StringUtils.repeat('e', 3)  = "eee"
 StringUtils.repeat('e', -2) = ""
 
```
Note: this method does not support padding with Unicode Supplementary Characters as they require a pair of chars to be represented. If you are needing to support full I18N of your applications consider using repeat(String, int) instead.
Parameters:

ch - character to repeat

repeat - number of times to repeat char, negative treated as zero

Returns:

String with repeated character

See Also:

repeat(String, int), Source

rightPad

public static java.lang.String rightPad(java.lang.String str,
                                        int size)

Right pad a String with spaces (' ').

The String is padded to the size of size.

 StringUtils.rightPad(null, *)   = null
 StringUtils.rightPad("", 3)     = "   "
 StringUtils.rightPad("bat", 3)  = "bat"
 StringUtils.rightPad("bat", 5)  = "bat  "
 StringUtils.rightPad("bat", 1)  = "bat"
 StringUtils.rightPad("bat", -1) = "bat"

Parameters:: str - the String to pad out, may be null; size - the size to pad to
Returns:: right padded String or original String if no padding is necessary, null if null String input
See Also:: Source

rightPad

public static java.lang.String rightPad(java.lang.String str,
                                        int size,
                                        char padChar)

Right pad a String with a specified character.

The String is padded to the size of size.

 StringUtils.rightPad(null, *, *)     = null
 StringUtils.rightPad("", 3, 'z')     = "zzz"
 StringUtils.rightPad("bat", 3, 'z')  = "bat"
 StringUtils.rightPad("bat", 5, 'z')  = "batzz"
 StringUtils.rightPad("bat", 1, 'z')  = "bat"
 StringUtils.rightPad("bat", -1, 'z') = "bat"

Parameters:: str - the String to pad out, may be null; size - the size to pad to; padChar - the character to pad with
Returns:: right padded String or original String if no padding is necessary, null if null String input
Since:: 2.0
See Also:: Source

rightPad

public static java.lang.String rightPad(java.lang.String str,
                                        int size,
                                        java.lang.String padStr)

Right pad a String with a specified String.

The String is padded to the size of size.

 StringUtils.rightPad(null, *, *)      = null
 StringUtils.rightPad("", 3, "z")      = "zzz"
 StringUtils.rightPad("bat", 3, "yz")  = "bat"
 StringUtils.rightPad("bat", 5, "yz")  = "batyz"
 StringUtils.rightPad("bat", 8, "yz")  = "batyzyzy"
 StringUtils.rightPad("bat", 1, "yz")  = "bat"
 StringUtils.rightPad("bat", -1, "yz") = "bat"
 StringUtils.rightPad("bat", 5, null)  = "bat  "
 StringUtils.rightPad("bat", 5, "")    = "bat  "

Parameters:: str - the String to pad out, may be null; size - the size to pad to; padStr - the String to pad with, null or empty treated as single space
Returns:: right padded String or original String if no padding is necessary, null if null String input
See Also:: Source

leftPad

public static java.lang.String leftPad(java.lang.String str,
                                       int size)

Left pad a String with spaces (' ').

The String is padded to the size of size.

 StringUtils.leftPad(null, *)   = null
 StringUtils.leftPad("", 3)     = "   "
 StringUtils.leftPad("bat", 3)  = "bat"
 StringUtils.leftPad("bat", 5)  = "  bat"
 StringUtils.leftPad("bat", 1)  = "bat"
 StringUtils.leftPad("bat", -1) = "bat"

Parameters:: str - the String to pad out, may be null; size - the size to pad to
Returns:: left padded String or original String if no padding is necessary, null if null String input
See Also:: Source

leftPad

public static java.lang.String leftPad(java.lang.String str,
                                       int size,
                                       char padChar)

Left pad a String with a specified character.

Pad to a size of size.

 StringUtils.leftPad(null, *, *)     = null
 StringUtils.leftPad("", 3, 'z')     = "zzz"
 StringUtils.leftPad("bat", 3, 'z')  = "bat"
 StringUtils.leftPad("bat", 5, 'z')  = "zzbat"
 StringUtils.leftPad("bat", 1, 'z')  = "bat"
 StringUtils.leftPad("bat", -1, 'z') = "bat"

Parameters:: str - the String to pad out, may be null; size - the size to pad to; padChar - the character to pad with
Returns:: left padded String or original String if no padding is necessary, null if null String input
Since:: 2.0
See Also:: Source

leftPad

public static java.lang.String leftPad(java.lang.String str,
                                       int size,
                                       java.lang.String padStr)

Left pad a String with a specified String.

Pad to a size of size.

 StringUtils.leftPad(null, *, *)      = null
 StringUtils.leftPad("", 3, "z")      = "zzz"
 StringUtils.leftPad("bat", 3, "yz")  = "bat"
 StringUtils.leftPad("bat", 5, "yz")  = "yzbat"
 StringUtils.leftPad("bat", 8, "yz")  = "yzyzybat"
 StringUtils.leftPad("bat", 1, "yz")  = "bat"
 StringUtils.leftPad("bat", -1, "yz") = "bat"
 StringUtils.leftPad("bat", 5, null)  = "  bat"
 StringUtils.leftPad("bat", 5, "")    = "  bat"

Parameters:: str - the String to pad out, may be null; size - the size to pad to; padStr - the String to pad with, null or empty treated as single space
Returns:: left padded String or original String if no padding is necessary, null if null String input
See Also:: Source

strip
```
public static java.lang.String strip(java.lang.String str,
                                     java.lang.String stripChars)
```
Strips any of a set of characters from the start and end of a String. This is similar to String.trim() but allows the characters to be stripped to be controlled.

A null input String returns null. An empty string ("") input returns the empty string.

If the stripChars String is null, whitespace is stripped as defined by Character.isWhitespace(char).
```
 StringUtils.strip(null, *)          = null
 StringUtils.strip("", *)            = ""
 StringUtils.strip("abc", null)      = "abc"
 StringUtils.strip("  abc", null)    = "abc"
 StringUtils.strip("abc  ", null)    = "abc"
 StringUtils.strip(" abc ", null)    = "abc"
 StringUtils.strip("  abcyx", "xyz") = "  abc"
 
```
Parameters:

str - the String to remove characters from, may be null

stripChars - the characters to remove, null treated as whitespace

Returns:

the stripped String, null if null String input

See Also:

Source

stripEnd

public static java.lang.String stripEnd(java.lang.String str,
                                        java.lang.String stripChars)

Strips any of a set of characters from the end of a String.

A null input String returns null. An empty string ("") input returns the empty string.

If the stripChars String is null, whitespace is stripped as defined by Character.isWhitespace(char).

 StringUtils.stripEnd(null, *)          = null
 StringUtils.stripEnd("", *)            = ""
 StringUtils.stripEnd("abc", "")        = "abc"
 StringUtils.stripEnd("abc", null)      = "abc"
 StringUtils.stripEnd("  abc", null)    = "  abc"
 StringUtils.stripEnd("abc  ", null)    = "abc"
 StringUtils.stripEnd(" abc ", null)    = " abc"
 StringUtils.stripEnd("  abcyx", "xyz") = "  abc"
 StringUtils.stripEnd("120.00", ".0")   = "12"

Parameters:: str - the String to remove characters from, may be null; stripChars - the set of characters to remove, null treated as whitespace
Returns:: the stripped String, null if null String input
See Also:: Source

stripStart

public static java.lang.String stripStart(java.lang.String str,
                                          java.lang.String stripChars)

Strips any of a set of characters from the start of a String.

A null input String returns null. An empty string ("") input returns the empty string.

If the stripChars String is null, whitespace is stripped as defined by Character.isWhitespace(char).

 StringUtils.stripStart(null, *)          = null
 StringUtils.stripStart("", *)            = ""
 StringUtils.stripStart("abc", "")        = "abc"
 StringUtils.stripStart("abc", null)      = "abc"
 StringUtils.stripStart("  abc", null)    = "abc"
 StringUtils.stripStart("abc  ", null)    = "abc  "
 StringUtils.stripStart(" abc ", null)    = "abc "
 StringUtils.stripStart("yxabc  ", "xyz") = "abc  "

Parameters:: str - the String to remove characters from, may be null; stripChars - the characters to remove, null treated as whitespace
Returns:: the stripped String, null if null String input
See Also:: Source

stripToEmpty

public static java.lang.String stripToEmpty(java.lang.String str)

Strips whitespace from the start and end of a String returning an empty String if null input.

This is similar to trimToEmpty(String) but removes whitespace. Whitespace is defined by Character.isWhitespace(char).

 StringUtils.stripToEmpty(null)     = ""
 StringUtils.stripToEmpty("")       = ""
 StringUtils.stripToEmpty("   ")    = ""
 StringUtils.stripToEmpty("abc")    = "abc"
 StringUtils.stripToEmpty("  abc")  = "abc"
 StringUtils.stripToEmpty("abc  ")  = "abc"
 StringUtils.stripToEmpty(" abc ")  = "abc"
 StringUtils.stripToEmpty(" ab c ") = "ab c"

Parameters:: str - the String to be stripped, may be null
Returns:: the trimmed String, or an empty String if null input
Since:: 2.0
See Also:: Source

wrap

public static java.lang.String wrap(java.lang.String str,
                                    int wrapLength)

Wraps a single line of text, identifying words by ' '.

New lines will be separated by the system property line separator. Very long words, such as URLs will not be wrapped.

Leading spaces on a new line are stripped. Trailing spaces are not stripped.

Examples
input	wrapLength	result
null	*	null
""	*	""
"Here is one line of text that is going to be wrapped after 20 columns."	20	"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."
"Click here to jump to the commons website - http://commons.apache.org"	20	"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"
"Click here, http://commons.apache.org, to jump to the commons website"	20	"Click here,\nhttp://commons.apache.org,\nto jump to the\ncommons website"

(assuming that '\n' is the systems line separator)

Parameters:: str - the String to be word wrapped, may be null; wrapLength - the column to wrap the words at, less than 1 is treated as 1
Returns:: a line with newlines inserted, null if null input
See Also:: Source

wrap

public static java.lang.String wrap(java.lang.String str,
                                    int wrapLength,
                                    java.lang.String newLineStr,
                                    boolean wrapLongWords)

Wraps a single line of text, identifying words by ' '.

Leading spaces on a new line are stripped. Trailing spaces are not stripped.

Examples
input	wrapLength	newLineString	wrapLongWords	result
null	*	*	true/false	null
""	*	*	true/false	""
"Here is one line of text that is going to be wrapped after 20 columns."	20	"\n"	true/false	"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."
"Here is one line of text that is going to be wrapped after 20 columns."	20	"<br />"	true/false	"Here is one line of<br />text that is going< br />to be wrapped after<br />20 columns."
"Here is one line of text that is going to be wrapped after 20 columns."	20	null	true/false	"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."
"Click here to jump to the commons website - http://commons.apache.org"	20	"\n"	false	"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"
"Click here to jump to the commons website - http://commons.apache.org"	20	"\n"	true	"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"

Parameters:: str - the String to be word wrapped, may be null; wrapLength - the column to wrap the words at, less than 1 is treated as 1; newLineStr - the string to insert for a new line, null uses the system property line separator; wrapLongWords - true if long words (such as URLs) should be wrapped
Returns:: a line with newlines inserted, null if null input
See Also:: Source

wrap

public static java.lang.String wrap(java.lang.String str,
                                    int wrapLength,
                                    java.lang.String newLineStr,
                                    boolean wrapLongWords,
                                    java.lang.String wrapOn)

Wraps a single line of text, identifying words by wrapOn.

Leading spaces on a new line are stripped. Trailing spaces are not stripped.

Examples
input	wrapLength	newLineString	wrapLongWords	wrapOn	result
null	*	*	true/false	*	null
""	*	*	true/false	*	""
"Here is one line of text that is going to be wrapped after 20 columns."	20	"\n"	true/false	" "	"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."
"Here is one line of text that is going to be wrapped after 20 columns."	20	"<br />"	true/false	" "	"Here is one line of<br />text that is going<br /> to be wrapped after<br />20 columns."
"Here is one line of text that is going to be wrapped after 20 columns."	20	null	true/false	" "	"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."
"Click here to jump to the commons website - http://commons.apache.org"	20	"\n"	false	" "	"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"
"Click here to jump to the commons website - http://commons.apache.org"	20	"\n"	true	" "	"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"
"flammable/inflammable"	20	"\n"	true	"/"	"flammable\ninflammable"

Parameters:: str - the String to be word wrapped, may be null; wrapLength - the column to wrap the words at, less than 1 is treated as 1; newLineStr - the string to insert for a new line, null uses the system property line separator; wrapLongWords - true if long words (such as URLs) should be wrapped; wrapOn - regex expression to be used as a breakable characters, if blank string is provided a space character will be used
Returns:: a line with newlines inserted, null if null input
See Also:: Source

escapeJavaString

public static java.lang.String escapeJavaString(java.lang.Object object,
                                                java.lang.String indent)

levenshteinDistance

public static int levenshteinDistance(java.lang.CharSequence left,
                                      java.lang.CharSequence right,
                                      int threshold)

Find the Levenshtein distance between two CharSequences if it's less than or equal to a given threshold.

This code is a copy of the limitedCompare method from Apache commons-text LevenshteinDistance.java.

This implementation follows from Algorithms on Strings, Trees and Sequences by Dan Gusfield and Chas Emerick's implementation of the Levenshtein distance algorithm from http://www.merriampark.com/ld.htm

 limitedCompare(null, *, *)             = IllegalArgumentException
 limitedCompare(*, null, *)             = IllegalArgumentException
 limitedCompare(*, *, -1)               = IllegalArgumentException
 limitedCompare("","", 0)               = 0
 limitedCompare("aaapppp", "", 8)       = 7
 limitedCompare("aaapppp", "", 7)       = 7
 limitedCompare("aaapppp", "", 6))      = -1
 limitedCompare("elephant", "hippo", 7) = 7
 limitedCompare("elephant", "hippo", 6) = -1
 limitedCompare("hippo", "elephant", 7) = 7
 limitedCompare("hippo", "elephant", 6) = -1

Parameters:: left - the first CharSequence, must not be null; right - the second CharSequence, must not be null; threshold - the target threshold, must not be negative
Returns:: result distance, or -1
See Also:: LevenshteinDistance.java

Class StringUtils

Method Summary

Methods inherited from class java.lang.Object

Method Detail

isEmpty

isBlank

isNotBlank

trim

trimToNull

trimToEmpty

equals

substring

substring

upperCase

lowerCase

capitalize

uncapitalize

startsWithIgnoreCase

repeat

repeat

rightPad

rightPad

rightPad

leftPad

leftPad

leftPad

strip

stripEnd

stripStart

stripToEmpty

wrap

wrap

wrap

escapeJavaString

levenshteinDistance