String.split()
Splits a string into an array of parts by a separator.
Available since: Java 1.4
Syntax
public String[] split(String regex)Parameters
| Parameter | Type | Description |
|---|---|---|
| regex | String | The separator, as a regular expression. There is a version with a second limit argument. |
Return value
String[]An array of strings, String[].
Examples
Splitting by a comma:
void main() {
String csv = "Anna,Oleg,Maria";
String[] names = csv.split(",");
IO.println(names.length);
IO.println(names[1]);
}Output:
3
OlegWords separated by any number of spaces:
void main() {
String text = "one two three";
for (String word : text.split("\\s+")) {
IO.println(word);
}
}Output:
one
two
threeA dot must be escaped — it is a special regex character:
void main() {
String ip = "192.168.0.1";
IO.println(ip.split(".").length);
IO.println(ip.split("\\.").length);
}Output:
0
4Notes
Empty strings at the end are dropped: "a,b,,".split(",") gives 2 elements. To keep them, pass -1 as the second argument: split(",", -1).
Escape the special characters ., |, +, *, ?, (, $ with two backslashes or wrap the separator in Pattern.quote().
See also
- String.join() — Joins strings with a separator.
- String.lines() — Splits a string at line breaks and returns the lines as a stream.
- String.strip() — Removes any Unicode whitespace from both ends of a string.
- Arrays.toString() — Returns the contents of an array as a string like [1, 2, 3].
Related recipes
In the tutorial
- String methods — The main String methods in Java: searching, substring, changing case, strip, replace, split, join, repeat and string checks.