Hutool 3.9

<dependency> <groupId>cn.hutool</groupId> <artifactId>hutool-core</artifactId> <version>3.9.0</version> </dependency>  <dependency> <groupId>cn.hutool</groupId> <artifactId>hutool-http</artifactId> <version>3.9.0</version> </dependency> <dependency> <groupId>cn.hutool</groupId> <artifactId>hutool-crypto</artifactId> <version>3.9.0</version> </dependency>

// 2. 日期处理 String now = DateUtil.now(); // 得到"2026-05-29 14:30:00" System.out.println("当前时间：" + now);

A wrapper around the Java Cryptography Extension (JCE). It simplified symmetrical encryption (AES, DES), asymmetrical encryption (RSA), and digest algorithms (MD5, SHA-1, SHA-256) into fluent, one-line executions. hutool-http

import cn.hutool.core.io.FileUtil; import java.io.File; import java.util.List; public class IoExample public static void main(String[] args) File file = new File("example.txt"); // Write text to a file with automatic UTF-8 encoding FileUtil.writeUtf8String("Hello, Hutool 3.9!", file); // Read lines cleanly into a list List lines = FileUtil.readUtf8Lines(file); for (String line : lines) System.out.println(line); // Clean up: Delete file safely without throwing checked exceptions FileUtil.del(file); Use code with caution. Cryptographic Operations ( SecureUtil ) Hutool 3.9

如果你曾被Java原生的 Calendar 折磨过，那么 DateUtil 绝对会让你感到相见恨晚。它把复杂的日期操作简化成了一行代码。

import cn.hutool.http.HttpUtil; import cn.hutool.core.date.DateUtil; import cn.hutool.core.util.StrUtil;

import cn.hutool.core.io.FileUtil; import java.util.List; public class FileExample public static void main(String[] args) String filePath = "/absolute/path/to/example.txt"; // 1. Write lines of text to a file (automatically creates missing directories) FileUtil.writeString("Hello Hutool 3.9!\nLine 2 Data", filePath, "UTF-8"); // 2. Read file completely into a clean String String content = FileUtil.readString(filePath, "UTF-8"); // 3. Read file line by line into a List List lines = FileUtil.readLines(filePath, "UTF-8"); // 4. Clean up / Delete file safely FileUtil.del(filePath); Use code with caution. Module C: Secure Data Encryption ( CryptoUtil ) <dependency> <groupId>cn

可以，但需要注意：3.9是一款较早的版本，安全补丁和BUG修复不会持续更新。如果你的项目对安全要求较高，建议优先考虑5.x系列。但在封闭的内网、内部管理系统等对安全要求不苛刻的场景中，3.9依然能胜任。

Hutool 3.9 was a significant iteration in the library's history, focusing on modularizing common Java tasks into easy-to-use utility classes. It is often described as a "Swiss Army knife" for Java developers. Key Features and Modules The 3.9 release improved several core areas: hutool-crypto

Handling dates using native Java 7/8 components can be error-prone and verbose. DateUtil simplifies formatting, parsing, and date arithmetic. hutool-http import cn

To help tailor any specific solutions, could you let me know you are looking to implement with Hutool 3.9, or if you are planning a migration to a newer version ? Share public link

Security is hard, but Hutool makes it simpler. It includes quick tools for locking and unlocking data. You can encrypt passwords or verify files using standard security formats with very little effort. 🚀 Why Developers Use It