Integer cannot be converted to boolean using "indexOf()"

Question

I'm trying to count how many times the word "ing" occurred in a string asked by a user, I'm having an error saying it cannot be converted.

I tried using s.indexOf("ing")

package javaapplication3;

import java.util.*;

public class JavaApplication3 {


public static void main(String[] args) {
  Scanner in = new Scanner(System.in);
    String s,q = null;
    String i = "ing";
    int count=0;
  System.out.println("Entrer une ligne de texte :");
  s = in.next();
  if ( s.indexOf("ing") ){
      count++;
  q = s.replaceAll("ing", "ed");
  }
  System.out.println("\"ing\" est occuree " +count +" fois.");
  System.out.println(q);
}
}

I expect the output would give me and count how many times it occurred but I'm having an error.

I think you want `if(s.indexOf("ing") != -1) { ... }` or `if(s.contains("ing")) { ... }` — Mark, Jan 30 '19 at 11:07
@ShubhDixit s.contais or s.indexOf() isn't counting all the word, it is giving me only the first time "ing" occurred. Any idea? — Raphael Eid, Jan 30 '19 at 11:09
Related: https://stackoverflow.com/questions/767759/occurrences-of-substring-in-a-string — MC Emperor, Jan 30 '19 at 11:11
Possible duplicate of [Occurrences of substring in a string](https://stackoverflow.com/questions/767759/occurrences-of-substring-in-a-string) — Mustapha Belmokhtar, Jan 30 '19 at 11:14

score 1 · Accepted Answer · answered Jan 30 '19 at 11:15

Use s = in.nextLine(); rather than next() to read the whole line

You need to count until the lookFor part is still in the word, each time replace the first occurence by something else, and continue using a while loop

String lookFor = "ing";
while (s.indexOf(lookFor) != -1) {
    count++;
    s = s.replaceFirst(lookFor, "ed");
}

same as

String lookFor = "ing";
while (s.contains(lookFor)) {
    count++;
    s = s.replaceFirst(lookFor, "ed");
}

score 0 · Answer 2 · answered Jan 30 '19 at 11:17

0

You should loop over your input till your string does not have the required literal available,

int count = 0;
while (s.indexOf("ing") != -1) {
    s = s.replaceFirst("ing", "");
    count++;
}
System.out.print("Total occurances : "+count);

answered Jan 30 '19 at 11:17

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Integer cannot be converted to boolean using "indexOf()"

2 Answers2