* for strings in Java

Question

In Python, there is a * operator for strings, I'm not sure what it's called but it does this:

>>> "h" * 9
"hhhhhhhhh"

Is there an operator in Java like Python's *?

There is no such operator in Java. – Marko Topolnik May 29 '13 at 11:30 — Marko Topolnik, May 29 '13 at 11:30

Sean Patrick Floyd · Answer 1 · 2013-05-29T11:45:43.480

9

Many libraries have such utility methods.

E.g. Guava:

String s = Strings.repeat("*",9);

String s = StringUtils.repeat("*", 9);

Both of these classes also have methods to pad a String's beginning or end to a certain length with a specified character.

edited May 29 '13 at 11:45

answered May 29 '13 at 11:31

score 5 · Answer 2 · answered May 29 '13 at 11:30

5

I think the easiest way to do this in java is with a loop:

String string = "";
for(int i=0; i<9; i++)
{
    string+="h";
}

answered May 29 '13 at 11:30

Lawrence Andrews

2

Note that if you're going to do a LOT of concatenations, you should use a StringBuilder for performance. (Corollary: If it finishes in a blink of an eye, no optimization needed.) – Patashu May 29 '13 at 11:31
2

String+=String in a loop is pure evil – Sean Patrick Floyd May 29 '13 at 11:33
See [Effective Java by Josh Bloch](http://www.amazon.com/Effective-Java-2nd-Joshua-Bloch/dp/0321356683), Item 51: Beware the performance of string concatenation – Sean Patrick Floyd May 29 '13 at 12:41

score 3 · Answer 3 · answered May 29 '13 at 11:32

3

you can use something like this :

String str = "abc";
String repeated = StringUtils.repeat(str, 3);

repeated.equals("abcabcabc");

answered May 29 '13 at 11:32

Yassering

3

Might want to add a note about where `StringUtils` comes from. – Paul Bellora May 29 '13 at 11:33
you r right , you should Use apache libraries (common-lang) . – Yassering May 29 '13 at 11:35

score 2 · Answer 4 · answered May 29 '13 at 11:46

There is no such operator in Java, but you can use Arrays.fill() or Apache Commons StringUtils.repeat() to achieve that result:

Assuming

    char src = 'x';
    String out;

with Arrays.fill()

    char[] arr = new char[10] ;
    Arrays.fill(arr,src);        
    out = new String(arr);

with StringUtils.repeat()

    out = StringUtils.repeat(src, 10);

score 1 · Answer 5 · answered May 29 '13 at 11:33

1

Use apache libraries (common-lang) : Stringutils.repeat(str, nb)

answered May 29 '13 at 11:33

mlwacosmos

score 1 · Answer 6 · answered Apr 13 '21 at 14:50

1

String.repeat(count) has been available since JDK 11. String.repeat(count)

answered Apr 13 '21 at 14:50

wickund

score 0 · Answer 7 · answered Oct 09 '15 at 00:46

0

There is no operator like that, but you could assign the sting "h" to a variable and use a for loop to print the variable a desired amount of times.

answered Oct 09 '15 at 00:46

Chris M

7 Answers7