Package com.norconex.commons.lang.text

Class StringUtil

java.lang.Object

com.norconex.commons.lang.text.StringUtil

public final class StringUtil
extends Object

String-related utility methods not found in popular libraries.

Since:

1.14.0

Field Summary

Fields

Modifier and Type	Field	Description
static final int	TRUNCATE_HASH_LENGTH

Method Summary

Modifier and Type	Method	Description
static int	countMatchesEnd(String str, String sub)	Counts the number of consecutive matches at end of a a string.
static int	countMatchesStart(String str, String sub)	Counts the number of consecutive matches from the beginning of a string.
static void	ifBlank(String str, Runnable runnable)	Consume the given string only if it is blank.
static void	ifNotBlank(String str, Consumer<String> consumer)	Consume the given string only if it is not blank.
static String	singular(String plural)	Converts an English plural word to singular one using very simple heuristics.
static String	singularOrElse(String plural, String defaultValue)	Converts an English plural word to singular one using very simple heuristics.
static String	trimEnd(String str)	Trims white spaces at the end of a string.
static String	trimStart(String str)	Trims white spaces at the beginning of a string.
static byte[]	truncateBytesWithHash(byte[] bytes, Charset charset, int maxByteLength)	Truncates character byte array text larger than the given max byte length and appends a hash value from the truncated text.
static byte[]	truncateBytesWithHash(byte[] bytes, Charset charset, int maxByteLength, String separator)	Truncates character byte array text larger than the given max byte length and appends a hash value from the truncated text, with an optional separator in-between.
static String	truncateBytesWithHash(String text, Charset charset, int maxByteLength)	Truncates text with size in bytes larger than the given max byte length and appends a hash value from the truncated text.
static String	truncateBytesWithHash(String text, Charset charset, int maxByteLength, String separator)	Truncates text with size in bytes larger than the given max byte length and appends a hash value from the truncated text, with an optional separator in-between.
static String	truncateWithHash(String text, int maxLength)	Truncate text larger than the given max length and appends a hash value from the truncated text.
static String	truncateWithHash(String text, int maxLength, String separator)	Truncate text larger than the given max length and appends a hash value from the truncated text, with an optional separator in-between.

Methods inherited from class java.lang.Object

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

Field Details

TRUNCATE_HASH_LENGTH

public static final int TRUNCATE_HASH_LENGTH

See Also:

• Constant Field Values

Method Details

ifBlank

public static void ifBlank(String str,
 Runnable runnable)

Consume the given string only if it is blank.

Parameters:

str - the string to consume

runnable - code to be executed

Since:

3.0.0

ifNotBlank

public static void ifNotBlank(String str,
 Consumer<String> consumer)

Consume the given string only if it is not blank.

Parameters:

str - the string to consume

consumer - string consumer

Since:

3.0.0

truncateWithHash

public static String truncateWithHash(String text,
 int maxLength)

Truncate text larger than the given max length and appends a hash value from the truncated text. The hash size has 10 digits. The hash is added to fit within the maximum length supplied. For this reason, the maxLength argument must be be minimum 10 for any truncation to occur. The hash is added without a separator. To insert a separator between the truncated text and the hash code, use truncateWithHash(String, int, String)

Parameters:

text - text to truncate

maxLength - maximum length the truncated text must have

Returns:

truncated text, or original text if no truncation required

truncateWithHash

public static String truncateWithHash(String text,
 int maxLength,
 String separator)

Truncate text larger than the given max length and appends a hash value from the truncated text, with an optional separator in-between. The hash size has 10 digits. The hash and separator are added to fit within the maximum length supplied. For this reason, the maxLength argument must be be minimum 10 + separator length for any truncation to occur.

Parameters:

text - text to truncate

maxLength - maximum length the truncated text must have

separator - string separating truncated text from hash code

Returns:

truncated text, or original text if no truncation required

truncateBytesWithHash

public static String truncateBytesWithHash(String text,
 Charset charset,
 int maxByteLength)
                                    throws CharacterCodingException

Truncates text with size in bytes larger than the given max byte length and appends a hash value from the truncated text. The hash size is equal to the byte length of 10 digits using the given charset. The hash and separator are added to fit within the maximum byte length supplied. For this reason, the maxByteLength argument must be be large enough for any truncation to occur.

Parameters:

text - text to truncate

charset - character encoding

maxByteLength - maximum byte length the truncated text must have

Returns:

truncated character byte array, or original text if no truncation required

Throws:

CharacterCodingException - character coding problem

truncateBytesWithHash

public static String truncateBytesWithHash(String text,
 Charset charset,
 int maxByteLength,
 String separator)
                                    throws CharacterCodingException

Truncates text with size in bytes larger than the given max byte length and appends a hash value from the truncated text, with an optional separator in-between. The hash size is equal to the byte length of 10 digits using the given charset. The hash and separator are added to fit within the maximum byte length supplied. For this reason, the maxByteLength argument must be be large enough for any truncation to occur.

Parameters:

text - text to truncate

charset - character encoding

maxByteLength - maximum byte length the truncated text must have

separator - string separating truncated text from hash code

Returns:

truncated character byte array, or original text if no truncation required

Throws:

CharacterCodingException - character coding problem

truncateBytesWithHash

public static byte[] truncateBytesWithHash(byte[] bytes,
 Charset charset,
 int maxByteLength)
                                    throws CharacterCodingException

Truncates character byte array text larger than the given max byte length and appends a hash value from the truncated text. The hash size is equal to the byte length of 10 digits using the given charset. The hash and separator are added to fit within the maximum byte length supplied. For this reason, the maxByteLength argument must be be large enough for any truncation to occur.

Parameters:

bytes - byte array of text to truncate

charset - character encoding

maxByteLength - maximum byte length the truncated text must have

Returns:

truncated character byte array, or original text if no truncation required

Throws:

CharacterCodingException - character coding problem

truncateBytesWithHash

public static byte[] truncateBytesWithHash(byte[] bytes,
 Charset charset,
 int maxByteLength,
 String separator)
                                    throws CharacterCodingException

Truncates character byte array text larger than the given max byte length and appends a hash value from the truncated text, with an optional separator in-between. The hash size is equal to the byte length of 10 digits using the given charset. The hash and separator are added to fit within the maximum byte length supplied. For this reason, the maxByteLength argument must be be large enough for any truncation to occur.

Parameters:

bytes - byte array of text to truncate

charset - character encoding

maxByteLength - maximum byte length the truncated text must have

separator - string separating truncated text from hash code

Returns:

truncated character byte array, or original text if no truncation required

Throws:

CharacterCodingException - character coding problem

trimEnd

public static String trimEnd(String str)

Trims white spaces at the end of a string.

Parameters:

str - the string to trim its end

Returns:

trimmed string

Since:

2.0.0

trimStart

public static String trimStart(String str)

Trims white spaces at the beginning of a string.

Parameters:

str - the string to trim its beginning

Returns:

trimmed string

Since:

2.0.0

countMatchesEnd

public static int countMatchesEnd(String str,
 String sub)

Counts the number of consecutive matches at end of a a string.

Parameters:

str - the string to check

sub - the substring to count

Returns:

number of matches from the start

Since:

2.0.0

countMatchesStart

public static int countMatchesStart(String str,
 String sub)

Counts the number of consecutive matches from the beginning of a string.

Parameters:

str - the string to check

sub - the substring to count

Returns:

number of matches from the end

Since:

2.0.0

singular

public static String singular(String plural)

Converts an English plural word to singular one using very simple heuristics. Returns null if the plural word is null. Else, returns the word unchanged if it cannot find a singular variant. You are encouraged to used a more sophisticated approach if accuracy is important.

Parameters:

plural - plural word

Returns:

singular word

Since:

3.0.0

singularOrElse

public static String singularOrElse(String plural,
 String defaultValue)

Converts an English plural word to singular one using very simple heuristics. Returns null if the plural word is null. Else, returns the default value if it cannot find a singular variant. You are encouraged to used a more sophisticated approach if accuracy is important.

Parameters:

plural - plural word

defaultValue - default value if singular can't be resolved

Returns:

singular word or null

Since:

3.0.0