package com.nisum.kafka_poc.practice; import java.util.Optional; public class NonRepeatedCharacters { public static Optional<Character> findFirstNonRepeatedChar(String message) { return message.chars() .mapToObj(c -> (char) c) .filter(ch -> message.indexOf(ch) == message.lastIndexOf(ch)) // Ensures uniqueness .findFirst(); } public static void main(String[] args) { String message = "Come here"; Optional<Character> result = findFirstNonRepeatedChar(message); result.ifPresent(System.out::println); // Output: 'C' } }