Find the Character at a Particular Index Example in Java

Introduction

Find The Character At A Particular Index is a classic Java console program that demonstrates the concept with complete source code and sample output. Strings are immutable objects in Java; the examples show comparison, searching and transformation.

This tutorial walks through the program line by line, explains how the logic works, and highlights best practices you can apply in your own code.

Definition

This method charAt() returns character at a particular index in the string.

Syntax

charAt(string,integer)

Find The Character At A Particular Index Example Program

import java.util.Scanner;

class FindCharacterAtIndex{
	public static void main(String[] args){
		String str="abcdefghijklmnopqrstuvwxyz";
		System.out.println("The string is: "+str);
		Scanner in=new Scanner(System.in);
		System.out.print("Enter the index at which the character is to be found: ");
		int index=in.nextInt();
		if(index<=26){
			System.out.println("The character at the index "+index+" is: "+str.charAt(index));
		}
		else{
			System.out.println("Enter a number between 0 and 25");
		}
	}
}

Sample Output

The string is: abcdefghijklmnopqrstuvwxyz
Enter the index at which the character is to be found: 8
The character at the index 8 is: i

When to use

Use string manipulation when cleaning user input, parsing text files or formatting messages.

How it works

1. Execution begins in the main method — the JVM calls this method when you run the class.

2. import java.util.Scanner; imports a class used later in the program.

3. String str="abcdefghijklmnopqrstuvwxyz"; updates a variable used in the calculation or output.

4. A println / print call writes text to the console — part of the sample output below.

5. A Scanner reads typed input from the keyboard (System.in).

6. A println / print call writes text to the console — part of the sample output below.

7. int index=in.nextInt(); updates a variable used in the calculation or output.

8. The if statement runs the nested code only when the condition is true.

Best Practices

• Use meaningful variable and class names that describe their purpose.
• Compile and run the program locally — modify values to see how output changes.
• Read compiler errors carefully; they usually point to the exact line to fix.

Common Mistakes

• Copying code without understanding each line — practice by changing one statement at a time.
• Mismatching the public class name and the .java filename.
• Forgetting semicolons at the end of statements.