Java Program to Convert a String to Lowercase

Introduction

Converting a string to lowercase is a common operation in text processing. This task helps you understand how to manipulate strings using built-in methods in Java. This guide will walk you through writing a Java program that converts a given string to lowercase.

Problem Statement

Create a Java program that:

• Prompts the user to enter a string.
• Converts the entire string to lowercase.
• Displays the lowercase string.

Example:

• Input: "HELLO WORLD"
• Output: "hello world"

Solution Steps

1. Read the String: Use the Scanner class to take the string as input from the user.
2. Convert the String to Lowercase: Use the toLowerCase() method to convert the string to lowercase.
3. Display the Lowercase String: Print the converted string.

Java Program

// Java Program to Convert a String to Lowercase
// Author: https://www.rameshfadatare.com/

import java.util.Scanner;

public class StringToLowercase {
  public static void main(String[] args) {
    // Step 1: Read the string from the user
    try (Scanner scanner = new Scanner(System.in)) {
      System.out.print("Enter a string: ");
      String input = scanner.nextLine();

      // Step 2: Convert the string to lowercase
      String lowercaseString = input.toLowerCase();

      // Step 3: Display the lowercase string
      System.out.println("Lowercase string: " + lowercaseString);
    }
  }
}

Explanation

Step 1: Read the String

• The Scanner class is used to read a string input from the user. The nextLine() method captures the entire line as a string.

Step 2: Convert the String to Lowercase

• The toLowerCase() method of the String class is used to convert the entire string to lowercase.

Step 3: Display the Lowercase String

• The program prints the converted lowercase string using System.out.println().

Output Example

Example:

Enter a string: HELLO WORLD
Lowercase string: hello world

Conclusion

This Java program demonstrates how to convert a user-input string to lowercase. It covers essential concepts such as string manipulation and using built-in methods, making it a valuable exercise for beginners learning Java programming.