Anagram Checker in Java

An anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once. For example, “listen” is an anagram of “silent”.

Program Structure

The Java program provided below checks if two strings are anagrams of each other. The program follows these steps:

1. Remove any spaces and convert both strings to lowercase for a case-insensitive comparison.
2. Check if the lengths of the two strings are equal. If not, they cannot be anagrams.
3. Sort the characters of both strings and compare the sorted results.
4. If the sorted strings are identical, the original strings are anagrams.

Java Program

import java.util.Arrays;

public class AnagramChecker {

    /**
     * Checks if two strings are anagrams.
     * 
     * @param str1 The first string.
     * @param str2 The second string.
     * @return true if the strings are anagrams, false otherwise.
     */
    public static boolean areAnagrams(String str1, String str2) {
        // Remove spaces and convert to lowercase
        str1 = str1.replaceAll("\\s", "").toLowerCase();
        str2 = str2.replaceAll("\\s", "").toLowerCase();
        
        // Check if lengths are different
        if (str1.length() != str2.length()) {
            return false;
        }
        
        // Convert strings to character arrays
        char[] arr1 = str1.toCharArray();
        char[] arr2 = str2.toCharArray();
        
        // Sort the character arrays
        Arrays.sort(arr1);
        Arrays.sort(arr2);
        
        // Compare sorted arrays
        return Arrays.equals(arr1, arr2);
    }

    public static void main(String[] args) {
        // Test cases
        String string1 = "Listen";
        String string2 = "Silent";

        // Check if the strings are anagrams
        boolean result = areAnagrams(string1, string2);

        // Output result
        if (result) {
            System.out.println(string1 + " and " + string2 + " are anagrams.");
        } else {
            System.out.println(string1 + " and " + string2 + " are not anagrams.");
        }
    }
}

Explanation of the Program

The program contains a method areAnagrams that performs the following actions:

• Normalization: It removes any spaces from the strings and converts them to lowercase to ensure the comparison is case-insensitive.
• Length Check: If the lengths of the two strings are different, they cannot be anagrams, so the method returns false.
• Sorting: Both strings are converted to character arrays, which are then sorted.
• Comparison: The sorted character arrays are compared. If they are equal, the original strings are anagrams.

The main method contains test cases that demonstrate the functionality of the areAnagrams method.