Upd [better] - Hutool 3.9
The team behind Hutool replaced several recursive algorithms with iterative versions and introduced for reflection results, drastically reducing GC pressure. Part 5: Migration Guide – Moving to Hutool 3.9 UPD If you are on Hutool 3.x or 4.x, here is your migration checklist. Step 1: Update Your Dependency Maven:
CronUtil.schedule("0 0 2 * * *", () -> FileUtil.clean(FileUtil.file("/temp/logs")); ); CronUtil.start(); // Runs a lightweight cron scheduler inside your JVM. The IdUtil module got objectId() – a MongoDB-like 12-byte ID generator, perfect for distributed logging without database sequences. Part 7: Common Pitfalls and Solutions in Hutool 3.9 UPD Pitfall 1: ClassCastException in Convert.convert() Cause: Using raw types. Solution: Always parameterize: Convert.convert(List.class, myObject) → Convert.convert(new TypeReference<List<String>>(){}, myObject) . Pitfall 2: Timezone Hell in DateUtil.beginOfDay() Fix: Use DateUtil.beginOfDay(date, TimeZone.getTimeZone("GMT+8")) . Pitfall 3: FileUtil.readLines() Memory Bloat Solution: For large files (>50 MB), use FileUtil.readUtf8Lines(File, LineConsumer ) streaming consumer introduced in 3.9 UPD. Part 8: Hutool 3.9 vs. Modern Java (17+) – Is It Still Worth It? With Java 17 introducing String::formatted , List::copyOf , and Files.writeString() , some argue Hutool is redundant. They are wrong. Here’s why Hutool 3.9 UPD still wins: Hutool 3.9 UPD
If you are starting a new Java 8–11 project, or maintaining a legacy system, upgrading to is a no-brainer. If you are already on a higher version, study 3.9's design patterns; its APIs set the standard for subsequent releases. The team behind Hutool replaced several recursive algorithms
| Feature | Java 17 JDK | Hutool 3.9 UPD | | :--- | :--- | :--- | | | Requires JavaMail + manual MIME | MailUtil.send() one-liner | | Captcha generation | Zero support | CaptchaUtil.createLineCaptcha() | | Tree structure building | Manual recursion | TreeUtil.build(list, "0") | | Parameter validation | Hibernate or manual | Validator.isChinese(name) | The IdUtil module got objectId() – a MongoDB-like
