Check whether given character present in string or not

Using ‘indexOf’ method, we can check whether given character is present in string or not. ‘indexOf()’ method return -1, if given character is not present in the string, else it return the index of the first occurrence of the character in the string.

Example

private static boolean isCharExist(String str, char ch) {

         if (str == null) {

                  throw new IllegalArgumentException("String can't be null");

         }

         return str.indexOf(ch) != -1;

}

Find the following working application.

App.java

package com.sample.app;

public class App {

 private static boolean isCharExist(String str, char ch) {
  if (str == null) {
   throw new IllegalArgumentException("String can't be null");
  }

  return str.indexOf(ch) != -1;
 }

 public static void main(String args[]) {
  String str = "Hello World";

  char ch = 'H';
  System.out.println("is " + ch + " exists in " + str + " : " + isCharExist(str, ch));

  ch = 'o';
  System.out.println("is " + ch + " exists in " + str + " : " + isCharExist(str, ch));

  ch = 'a';
  System.out.println("is " + ch + " exists in " + str + " : " + isCharExist(str, ch));
 }

}

Output

is H exists in Hello World : true

is o exists in Hello World : true

is a exists in Hello World : false

You may like

Miscellaneous

Interview Questions

Programming Questions

Get LocalDateTime from long epoch time

Compare two dates without time portion

Convert LocalDate to Date

Convert CharSequence to String

Delete all the files in a directory