How to count the number of sub string from a split in java

Question

I have this piece of code in my java class

mystring  = mysuperstring.split("/");

I want to know how many sub-string is created from the split.

In normal situation, if i want to access the first sub-string i just write

mystring[0];

Also, i want to know if mystring[5] exist or not.

NPE · Accepted Answer · 2012-02-29T13:53:57.703

16

I want to know how many sub-string is created from the split.

Since mystring is an array, you can simply use mystring.length to get the number of substrings.

Also, i want to know if mystring[5] exist or not.

To do this:

if (mystring.length >= 6) { ... }

edited Feb 29 '12 at 13:53

answered Feb 29 '12 at 13:47

NPE

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so i want to check if mystring[5] exist, i must write if(mystring.length==5) { do something } – sameer Feb 29 '12 at 13:51
@sameer: `if (mystring.length >= 6) { ... }` – NPE Feb 29 '12 at 13:54

score 10 · Answer 2 · answered Feb 29 '12 at 13:48

10

mystring  = mysuperstring.split("/");
int size = mystring.length;

remember that arrays are zero indexed, so where length = 5, the last element will be indexed with 4.

answered Feb 29 '12 at 13:48

NimChimpsky

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score 3 · Answer 3 · answered Sep 05 '14 at 21:31

3

It's a simple way to count the sub-strings

word.split('/').length;

You can see an example of this implementation here.

answered Sep 05 '14 at 21:31

li_developer

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score 0 · Answer 4 · answered May 14 '21 at 11:40

I wanted to demo a dumy token validation. So I tried to split by dot (.). It did not worked. So, I wonder and checked out an hour with no luck. After a while, when randomly trying I added escape character before dot and thank god it worked :D.

The reason is split takes string as regex. I checked why when writing an answer here:

You are splitting on the regex ., which means "any character"

int len = accessToken.split("\\.").length;

String I wanted to check

String accessToken = Bearer 1111.1111.11111 // demonstration purpose dumy

Output:

score 0 · Answer 5 · answered Feb 29 '12 at 13:50

Try this one & tell me if it works.

import java.util.regex.Pattern;

public class CountSubstring {
    public static int countSubstring(String subStr, String str){
        // the result of split() will contain one more element than the delimiter
        // the "-1" second argument makes it not discard trailing empty strings
        return str.split(Pattern.quote(subStr), -1).length - 1;
    }

    public static void main(String[] args){
        System.out.println(countSubstring("th", "the three truths"));
        System.out.println(countSubstring("abab", "ababababab"));
        System.out.println(countSubstring("a*b", "abaabba*bbaba*bbab"));
    }
}

score 0 · Answer 6 · answered Feb 29 '12 at 13:54

0

I think you must read about split and array, please find the links.

if you read about split function it returns Array of String.

and now you should read about Array and its size

answered Feb 29 '12 at 13:54

dku.rajkumar

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How to count the number of sub string from a split in java

6 Answers6