如何使用java从给定的字符串中获取精确匹配的关键字？

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class KeywordMatcher {
    public static void main(String[] args) {
        String keyword = "cloud"; // 要匹配的关键字
        String input = "This is a cloud computing example.";

        Pattern pattern = Pattern.compile("\\b" + keyword + "\\b", Pattern.CASE_INSENSITIVE);
        Matcher matcher = pattern.matcher(input);

        while (matcher.find()) {
            String matchedKeyword = matcher.group();
            System.out.println("匹配到的关键字: " + matchedKeyword);
        }
    }
}

public class KeywordMatcher {
    public static void main(String[] args) {
        String keyword = "cloud"; // 要匹配的关键字
        String input = "This is a cloud computing example.";

        int index = input.indexOf(keyword);
        while (index != -1) {
            String matchedKeyword = input.substring(index, index + keyword.length());
            System.out.println("匹配到的关键字: " + matchedKeyword);

            index = input.indexOf(keyword, index + keyword.length());
        }
    }
}