Hutool | 3.9

// 3. CollUtil: safe operations on collections List<String> list = CollUtil.newArrayList("a", "b", "c"); Console.log("Join result: {}", CollUtil.join(list, "-"));

// 2. StrUtil: check if string is blank String input = " Hutool 3.9 "; if (StrUtil.isNotBlank(input)) { Console.log("Trimmed: '{}'", StrUtil.trim(input)); } hutool 3.9

// 4. SecureUtil: simple MD5 String password = "admin123"; String md5Hex = SecureUtil.md5(password); Console.log("MD5 of '{}': {}", password, md5Hex); } } list = CollUtil.newArrayList("a"