Can I multiply strings in Java to repeat sequences

Question

I have something like the following   int i   3  String someNum    123     I d like to append i  0 s to the someNum string   Does it have some way I can multiply a string to repeat it like Python does   So I could just go   someNum   sumNum     0    3     or something similar   Where  in this case  my final result would be    123000

User · Answer

A generalisation of Dave Hartnoll s answer  I am mainly taking the concept ad absurdum  maybe don t use that in anything where you need speed   This allows one to fill the String up with i characters following a given pattern   int i   3  String someNum    123   String pattern    789   someNum     00000000000000000000  replaceAll  0  pattern  substring 0  i     If you don t need a pattern but just any single character you can use that  it s a tad faster    int i   3  String someNum    123   char c    7   someNum     00000000000000000000  replaceAll  0  c  substring 0  i

User · Answer

No  but you can in Scala   And then compile that and run it using any Java implementation       Now  if you want to do it the easy way in java  use the Apache commons-lang package  Assuming you re using maven  add this dependency to your pom xml        lt dependency gt           lt groupId gt commons-lang lt  groupId gt           lt artifactId gt commons-lang lt  artifactId gt           lt version gt 2 4 lt  version gt       lt  dependency gt    And then use StringUtils repeat as follows   import org apache commons lang StringUtils     someNum   sumNum   StringUtils repeat  0   3

User · Answer

No  Java does not have this feature  You d have to create your String using a StringBuilder  and a loop of some sort

User · Answer

No  you can t  However you can use this function to repeat a character   public String repeat char c  int times       StringBuffer b   new StringBuffer         for int i 0 i  amp lt  times i             b append c              return b toString        Disclaimer  I typed it here  Might have mistakes

User · Answer

Java 8 provides a way  albeit a little clunky   As a method   public static String repeat String s  int n        return Stream generate    - gt  s  limit n  collect Collectors joining           or less efficient  but nicer looking IMHO   public static String repeat String s  int n        return Stream generate    - gt  s  limit n  reduce  a  b  - gt  a   b

User · Answer

we can create multiply strings using   in python but not in java you can use for loop in your case   String sample  123   for int i 0 i lt 3 i      sample   0

User · Answer

With Guava   Joiner on     join Collections nCopies i  someNum

User · Answer

Google Guava provides another way to do this with Strings repeat     String repeated   Strings repeat  pete and re   42

User · Answer

Simple way of doing this   private String repeatString String s int count       StringBuilder r   new StringBuilder        for  int i   0  i  lt  count  i              r append s             return r toString

User · Answer

String  repeat  Use String  repeat in Java 11 and later   Examples   A  repeat  3         AAA   And the example from the Question   int i   3    frequency to repeat String someNum    123      initial string String ch    0      character to append  someNum   someNum   ch repeat i      formulation of the string System out println someNum      would result in output --  123000

User · Answer

I don t believe Java natively provides this feature  although it would be nice  I write Perl code occasionally and the x operator in Perl comes in really handy for repeating strings   However StringUtils in commons-lang provides this feature  The method is called repeat    Your only other option is to build it manually using a loop

User · Answer

If you re repeating single characters like the OP  and the maximum number of repeats is not too high  then you could use a simple substring operation like this   int i   3  String someNum    123   someNum     00000000000000000000  substring 0  i

User · Answer

Two ways comes to mind   int i   3  String someNum    123       Way 1  char   zeroes1   new char i   Arrays fill zeroes1   0    String newNum1   someNum   new String zeroes1   System out println newNum1      123000     Way 2  String zeroes2   String format   0    i    d   0   String newNum2   someNum   zeroes2  System out println newNum2      123000   Way 2 can be shortened to   someNum    String format   0    i    d   0   System out println someNum      123000   More about String format   is available in its API doc and the one of java util Formatter

User · Answer

Similar to what has already been said   public String multStuff String first  String toAdd  int amount         String append           for  int i   1  i  lt   amount  i              append    toAdd                           return first   append      Input multStuff  123    0   3    Output  123000

User · Answer

with Dollar   String s    123       0   repeat 3      123000

User · Answer

I created a method that do the same thing you want  feel free to try this   public String repeat String s  int count        return count  gt  0   s   repeat s  --count

User · Answer

There s no shortcut for doing this in Java like the example you gave in Python   You d have to do this   for   i  gt  0  i--        somenum   somenum    0

User · Answer

The simplest way is   String someNum    123000   System out println someNum

User · Answer

The easiest way in plain Java with no dependencies is the following one-liner   new String new char generation   replace   0    -     Replace generation with number of repetitions  and the  -  with the string  or char  you want repeated   All this does is create an empty string containing n number of 0x00 characters  and the built-in String replace method does the rest   Here s a sample to copy and paste   public static String repeat int count  String with        return new String new char count   replace   0   with      public static String repeat int count        return repeat count           public static void main String   args        for  int n   0  n  lt  10  n              System out println repeat n      Hello               for  int n   0  n  lt  10  n              System out println repeat n    -         Hello

[java] Can I multiply strings in Java to repeat sequences?

Examples related to java

Examples related to string