public final class Strings extends Object
Modifier and Type | Field | Description |
---|---|---|
static String |
EMPTY |
The empty string.
|
static String |
LINE_SEPARATOR |
OS-dependent line separator, defaults to
"\n" if the system property ""line.separator" cannot be
read. |
Modifier and Type | Method | Description |
---|---|---|
static String |
dquote(String str) |
Returns a double quoted string.
|
static boolean |
isBlank(String s) |
Checks if a String is blank.
|
static boolean |
isEmpty(CharSequence cs) |
Checks if a CharSequence is empty ("") or null.
|
static boolean |
isNotBlank(String s) |
Checks if a String is not blank.
|
static boolean |
isNotEmpty(CharSequence cs) |
Checks if a CharSequence is not empty ("") and not null.
|
static String |
join(Iterable<?> iterable,
char separator) |
Joins the elements of the provided
Iterable into
a single String containing the provided elements. |
static String |
join(Iterator<?> iterator,
char separator) |
Joins the elements of the provided
Iterator into
a single String containing the provided elements. |
static String |
quote(String str) |
Returns a quoted string.
|
String |
toRootUpperCase(String str) |
Shorthand for
str.toUpperCase(Locale.ROOT); |
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 . |
public static final String EMPTY
public static final String LINE_SEPARATOR
"\n"
if the system property ""line.separator"
cannot be
read.public static String dquote(String str)
str
- a String"str"
public static boolean isBlank(String s)
null
, empty, or when trimmed using
String.trim()
is empty.s
- the String to check, may be null
true
if the String is null
, empty, or trims to empty.public static boolean isEmpty(CharSequence cs)
Checks if a CharSequence is empty ("") or null.
Strings.isEmpty(null) = true Strings.isEmpty("") = true Strings.isEmpty(" ") = false Strings.isEmpty("bob") = false Strings.isEmpty(" bob ") = false
NOTE: This method changed in Lang version 2.0. It no longer trims the CharSequence. That functionality is available in isBlank().
Copied from Apache Commons Lang org.apache.commons.lang3.StringUtils.isEmpty(CharSequence)
cs
- the CharSequence to check, may be nulltrue
if the CharSequence is empty or nullpublic static boolean isNotBlank(String s)
isBlank(String)
.s
- the String to check, may be null
true
if the String is non-null
and has content after being trimmed.public static boolean isNotEmpty(CharSequence cs)
Checks if a CharSequence is not empty ("") and not null.
Strings.isNotEmpty(null) = false Strings.isNotEmpty("") = false Strings.isNotEmpty(" ") = true Strings.isNotEmpty("bob") = true Strings.isNotEmpty(" bob ") = true
Copied from Apache Commons Lang org.apache.commons.lang3.StringUtils.isNotEmpty(CharSequence)
cs
- the CharSequence to check, may be nulltrue
if the CharSequence is not empty and not nullpublic static String quote(String str)
str
- a String'str'
public String toRootUpperCase(String str)
str.toUpperCase(Locale.ROOT);
str
- The string to upper case.String.toLowerCase(Locale)
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.
Strings.trimToNull(null) = null Strings.trimToNull("") = null Strings.trimToNull(" ") = null Strings.trimToNull("abc") = "abc" Strings.trimToNull(" abc ") = "abc"
Copied from Apache Commons Lang org.apache.commons.lang3.StringUtils.trimToNull(String)
str
- the String to be trimmed, may be nullnull
if only chars <= 32, empty or null String inputpublic static String join(Iterable<?> iterable, char separator)
Joins the elements of the provided Iterable
into
a single String containing the provided elements.
No delimiter is added before or after the list. Null objects or empty strings within the iteration are represented by empty strings.
iterable
- the Iterable
providing the values to join together, may be nullseparator
- the separator character to usenull
if null iterator inputpublic static String join(Iterator<?> iterator, char separator)
Joins the elements of the provided Iterator
into
a single String containing the provided elements.
No delimiter is added before or after the list. Null objects or empty strings within the iteration are represented by empty strings.
iterator
- the Iterator
of values to join together, may be nullseparator
- the separator character to usenull
if null iterator inputCopyright © 1999-2018. All Rights Reserved.
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