How do I split or tokenize a string only when 2 delimiters are present together (adjacent to each other)

Question

I am reading in lines,and I need to split each line when the delimiter ; (semicolon + space) is present. Each line is as follows: s1; s2 s3; s4. I want to split this line where ; (semicolon + space) exists. I want to split only where semicolon and space are adjacent to each other, where a space follows a semicolon.

How would I do this using StringTokenizer?

I have already tried split("; ") but this splits the String at every occurrence of a space.

I have also tried new StringTokenizer(strLine,"\s*;\s+"), but this splits at every occurrence of 's'.

String[] parsedStr = inputString.split(...);

StringTokenizer st = new StringTokenizer(...);

I expect the output to be:

("s1","s2 s3","s4") Every token should be an element within this array.

NOT

("s1"," s2 s3"," s4")

NOR

("s1","s2","s3","s4")

Are you sure? In my experience `inputString.split("; ")` works really well. — Roland Illig, May 03 '19 at 05:18
Please post a minimal but complete program. My guess is that the bug is not in the `String.split` call but somewhere else. — Roland Illig, May 03 '19 at 16:20

MBD · Answer 1 · 2019-05-03T06:05:05.677

0

You can use regex with "\\s*;\\s+". It will remove any initial or trailing spaces. Also requires ';' to be followed with at least 1 space.

        String inputString = "s1; s2 s3; s4;s5";
        String[] parsedStr = inputString.split("\\s*;\\s+");

        System.out.print(Arrays.asList(parsedStr)); // ["s1", "s2 s3", "s4;s5"]

Edit:

If you need to split by semicolon and exact one space and keep the other spaces, you can modify the above solution as follows:

        String inputString = "s1; s2 s3; s4;s5; s6;  s7;";
        String[] parsedStr = inputString.split(";\\s{1}");

        System.out.print(Arrays.asList(parsedStr)); // ["s1", "s2 s3", "s4;s5", "s6", " s7;"]

edited May 03 '19 at 06:05

answered May 03 '19 at 05:21

MBD

1
1
1

I tried the code, but get "s4" and "s5" as two strings, not "s4;s5" – Blangero May 03 '19 at 05:46
Sorry, I fixed it. You need \\s+ (at least one space) instead of \\s* (0 or more) after ';' – MBD May 03 '19 at 05:48
Yes, now "s4;s5" shows. but if the input is "s1; s2 s3; s4;s5";( two space in front of s2), then other issue raises. maybe this is not a good direction for solving the problem : - ) – Blangero May 03 '19 at 05:50
no, I mean when there are two spaces in front of "s2 s3", then the result should be " s2 s3" ( with one space in front of s2). but \\s* removes all the spaces. – Blangero May 03 '19 at 05:58
Then you should specify the exact number of the trailing spaces, like that ";\\s{1}". I will update my answer. – MBD May 03 '19 at 06:01
I tried this using a StringTokenizer, st = new StringTokenizer(strLine, "\\s*;\\s+"); but it gives me a new issue, spliting at every occurrence of "s". – Danny May 03 '19 at 15:55

score 0 · Answer 2 · answered May 03 '19 at 06:33

0

As per your previous question, the solution would be as below :

   public class Split {
    public static void main(String[] args) {
        String inputString = "s1; s2 s3; s4;s5";
        String[] parsedStr = inputString.split("; | |;");
        System.out.print(Arrays.asList(parsedStr));
    } }

Since, you have edited your problem statement, the solution will be simple like :

inputString.split("; ");

answered May 03 '19 at 06:33

Utkarsh Bhatt

143
5
10

This still splits at every occurrence of space. – Danny May 03 '19 at 15:51

Liam Wilson · Answer 3 · 2019-05-03T05:40:07.887

-1

public static void main(String [] args){
 java.util.Scanner input=new java.util.Scanner
                        ("s1; s2 s3; s4").useDelimiter("\\s*; \\s*");

       while(input.hasNext())
       {
       System.out.print(input.next()+",");
       }
  input.close();
}

edited May 03 '19 at 05:40

answered May 03 '19 at 05:15

Liam Wilson

127
7

This code will also split on a semicolon _without_ a trailing space. – Roland Illig May 03 '19 at 05:20
i got that part , but in the expected output there is a space btw s2 and s3 – Liam Wilson May 03 '19 at 05:22
Yep, that's _one example_, and the specification says multiple times: the delimiter is _exactly_ semicolon-space. – Roland Illig May 03 '19 at 05:24

How do I split or tokenize a string only when 2 delimiters are present together (adjacent to each other)

3 Answers3