net.logstash.logback.util

Class StringUtils

java.lang.Object

net.logstash.logback.util.StringUtils

public class StringUtils
extends Object

Operations on String that are null safe.

Largely inspired by Apache Commons Lang3.

Note: This class is for internal use only and subject to backward incompatible change at any time.

Author:

brenuart

Method Summary

Modifier and Type	Method and Description
static boolean	isBlank(CharSequence cs) Checks if a CharSequence is empty (""), null or whitespace only.
static boolean	isEmpty(CharSequence cs) Checks if a CharSequence is empty ("") or null.
static int	length(CharSequence cs) Gets a CharSequence length or 0 if the CharSequence is null.
static String	trim(String str) Removes control characters (char <= 32) from both ends of this String, handling null by returning null.
static String	trimToEmpty(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 String	trimToNull(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.

Methods inherited from class java.lang.Object

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

Method Detail

trim

public static String trim(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

trimToEmpty

public static String trimToEmpty(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

trimToNull

public static String trimToNull(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

isEmpty

public static boolean isEmpty(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
 

Parameters:

cs - the CharSequence to check, may be null

Returns:

true if the CharSequence is empty or null

isBlank

public static boolean isBlank(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

length

public static int length(CharSequence cs)

Gets a CharSequence length or 0 if the CharSequence is null.

Parameters:

cs - a CharSequence or null

Returns:

CharSequence length or 0 if the CharSequence is null.