Hutool 3.9: [repack]

A lightweight, high-performance JSON parser integrated directly into the toolset. 4. Historical Context: The Transition to 4.x/5.x

import cn.hutool.crypto.SecureUtil; import cn.hutool.crypto.symmetric.SymmetricAlgorithm; import cn.hutool.crypto.symmetric.SymmetricCrypto; public class CryptoExample public static void main(String[] args) String secretData = "SensitiveUserPassword123"; // 1. Fast MD5 / SHA-256 Hashing String md5Hex = SecureUtil.md5(secretData); String sha256Hex = SecureUtil.sha256(secretData); // 2. AES Encryption and Decryption byte[] key = SecureUtil.generateKey(SymmetricAlgorithm.AES.getValue()).getEncoded(); SymmetricCrypto aes = SecureUtil.aes(key); // Encrypt String encryptedHex = aes.encryptHex(secretData); // Decrypt String decryptedStr = aes.decryptStr(encryptedHex); System.out.println("Decrypted Match: " + secretData.equals(decryptedStr)); Use code with caution. Module D: Lightweight HTTP Engine ( HttpUtil ) Hutool 3.9

Upgrading is painless. If you are using Maven or Gradle: Fast MD5 / SHA-256 Hashing String md5Hex = SecureUtil

To understand the importance of the 3.x series, it helps to look at the project's journey. Hutool was created by a Chinese developer, Looly (also known as Lu Xiaodai), in 2014. It started as a personal collection of utility classes, aiming to simplify Java and reduce repetitive code. The project officially launched on GitHub in early 2014. The early versions, part of the , focused on foundational tools like string ( StrUtil ) and date ( DateUtil ) handling, using a core design principle of static method encapsulation that remains central today. If you are using Maven or Gradle: To