public final class Strings extends Object
Modifier and Type | Method and Description |
---|---|
static String |
emptyToNull(String string)
Returns the given string if it is nonempty;
null otherwise. |
static boolean |
isNullOrEmpty(String string)
Returns
true if the given string is null or is the empty string. |
static String |
nullToEmpty(String string)
Returns the given string if it is non-null; the empty string otherwise.
|
static String |
repeat(String string,
int count)
Returns a string consisting of a specific number of concatenated copies of an input string.
|
public static String nullToEmpty(@Nullable String string)
string
- the string to test and possibly returnstring
itself if it is non-null; ""
if it is null@Nullable public static String emptyToNull(@Nullable String string)
null
otherwise.string
- the string to test and possibly returnstring
itself if it is nonempty; null
if it is empty or nullpublic static boolean isNullOrEmpty(@Nullable String string)
true
if the given string is null or is the empty string.
Consider normalizing your string references with nullToEmpty(java.lang.String)
. If you do, you can
use String.isEmpty()
instead of this method, and you won't need special null-safe forms
of methods like String.toUpperCase(java.util.Locale)
either. Or, if you'd like to normalize "in the other
direction," converting empty strings to null
, you can use emptyToNull(java.lang.String)
.
string
- a string reference to checktrue
if the string is null or is the empty stringpublic static String repeat(String string, int count)
repeat("hey", 3)
returns the string "heyheyhey"
.string
- any non-null stringcount
- the number of times to repeat it; a nonnegative integerstring
repeated count
times (the empty string if
count
is zero)IllegalArgumentException
- if count
is negativeCopyright © 2020. All rights reserved.