Java String - indexOf() Method

The java.lang.String.indexOf() method is used to find out the index number for first occurrence of specified character in the given string.

Syntax

public int indexOf(int ch)

Parameters

`ch`	specify the character to search for.

Return Value

Returns the index number for first occurrence of specified character. Returns -1 if there is no such occurrence.

Exception

NA.

Example:

In the example below, indexOf() method is used to find out the index number for first occurrence of specified character in the given string.

import java.lang.*;

public class MyClass {
  public static void main(String[] args) {
    String MyString = "Java is a programming language. Learning Java is fun.";
    
    //index number of first occurrence 
    //of 'J' in the given string
    System.out.println(MyString.indexOf('J'));  
  }
}

The output of the above code will be:

❮ Java.lang - String