Hutool 3.9 Upd May 2026
The announcement echoed through Maven Central like a town crier’s bell:
Hutool 3.9 is released! New features, better performance, and cleaner APIs!
The developers rejoiced. They updated their pom.xml files, ran mvn clean install, and watched their tests turn green. The release was smooth. Too smooth.
Security is where Hutool 3.9 UPD shined brightest. It added support for SM2/SM3/SM4 (Chinese National Cipher Standards), making Hutool the first lightweight Java utility library to support state secrets out-of-the-box without Bouncy Castle configuration hell.
Key additions:
Recommended migration steps:
Using the new CronUtil in 3.9 UPD:
CronUtil.schedule("0 0 2 * * *", () ->
FileUtil.clean(FileUtil.file("/temp/logs"));
);
CronUtil.start(); // Runs a lightweight cron scheduler inside your JVM.
If you meant a different version (e.g., 3.9.0 specifically) or a different library, let me know and I can refine the answer.
Hutool is a lightweight, comprehensive Java utility library designed to simplify common development tasks by encapsulating complex APIs into simple static methods. Overview of Hutool 3.x Updates
The 3.x series focused on stabilizing core modules and expanding utility coverage for modern Java development. Key highlights typically included in these updates include:
Core Module Enhancements: Improvements to the cn.hutool.core package, offering better performance for date and time processing (e.g., DateUtil), string manipulation, and collection handling.
IO and File Utilities: Streamlined methods for file reading, writing, and stream operations to minimize boilerplate code.
Enhanced Security Tools: Refinements in encryption/decryption utilities within the cn.hutool.crypto package, making standard algorithms more accessible.
HTTP Client Optimization: Updates to the cn.hutool.http module for easier RESTful service consumption and response handling. Getting Started with Hutool
You can integrate the library into your project using Maven Central or Gradle: Maven Dependency: Hutool 3.9 UPD
<dependency> <groupId>cn.hutoolgroupId> <artifactId>hutool-allartifactId> <version>3.9.0version> dependency> Use code with caution. Copied to clipboard Key Documentation:
Official Website: hutool.cn for API references and tutorials.
GitHub Repository: chinabugotech/hutool for source code and contribution. hutool/README-EN.md at v5-master - GitHub
Hutool 3.9 UPD an update for a specialized BMW coding and diagnostic software tool
. It is primarily used by automotive enthusiasts and professionals for advanced operations on BMW head units, particularly the (Next Big Thing Evolution) systems.
The core features and capabilities associated with this version include: EEPROM Wiping
: This is the most critical function of the 3.9 update. It allows users to "wipe" the EEPROM of an NBTevo unit, which is often necessary when retrofitting a used head unit into a different vehicle or recovering a unit after a failed firmware update. Support for Newer I-Steps
: This version is specifically required for handling BMWs with newer integration levels (I-Step), such as the
series. Older versions of the tool cannot communicate effectively with these newer firmware versions to reset or code the unit. SSH and SSH-over-USB Access
: It facilitates enabling SSH access to the head unit, which allows for deep-level file system modifications, custom patching, and feature activation (like CarPlay or Video in Motion). Script Execution
: The tool enables running custom scripts directly on the BMW operating system to automate coding tasks or bypass security certificates (FSC codes). Virginizing Units
: By clearing stored vehicle data (VIN and certificates), the tool "virginizes" the hardware so it can be correctly matched to a new car's FA (Financial Assembly) configuration. Are you looking to use this for a project or to fix a specific CAFD coding error NBTEvo cannot write CAFD after i-step update - Bimmerpost
Exploring Hutool 3.9: Key Updates and Performance Enhancements
In the ecosystem of Java development, efficiency is often measured by how much "boilerplate" code you can eliminate. For years, Hutool has stood out as a premier "Swiss Army Knife" for Java developers, providing a comprehensive set of utilities that simplify everything from file manipulation to cryptographic operations. The announcement echoed through Maven Central like a
The release of Hutool 3.9 marked a significant milestone in the library’s evolution, focusing on refining core tools and expanding support for modern development workflows. Here is a deep dive into the most impactful updates in version 3.9. 1. Strengthened Cryptography (Crypto) Module
One of the most notable UPD (updates) in 3.9 is the enhancement of the Hutool-crypto package. Security requirements are constantly shifting, and version 3.9 addressed this by:
BCrypt Support: Improved implementation of the BCrypt hashing algorithm, making it easier to handle secure password storage with built-in salting.
SM2/SM3/SM4 Optimization: For developers working with Chinese national standard (Guomi) algorithms, 3.9 provided better stability and performance for these specific cryptographic ciphers. 2. Enhanced HTTP Client Capabilities
Hutool-http is often preferred over heavier libraries like Apache HttpClient for its simplicity. In 3.9, several refinements were made to the HttpRequest and HttpResponse classes:
Timeout Handling: More granular control over connection and read timeouts.
Cookie Management: Refined automated cookie handling, allowing for more seamless session persistence during multi-step web scraping or API testing. 3. Date and Time Utilities (DateUtil)
The DateUtil class is perhaps the most used part of Hutool. The 3.9 update focused on "safety" and "localization":
Parsing Robustness: Version 3.9 introduced smarter string-to-date parsing, capable of identifying more esoteric date formats without requiring explicit pattern strings.
Performance: Internal optimizations reduced the overhead when performing massive batch conversions of timestamps. 4. File and IO Improvements
Working with files in Java can be notoriously verbose. Hutool 3.9 streamlined this further:
WatchMonitor Enhancements: The file monitoring utility became more stable, particularly on Windows environments, reducing the "missed event" bug that occasionally plagued earlier versions.
Tailer Functionality: Improvements to the Tailer class allowed for smoother real-time log monitoring (similar to the Linux tail -f command). 5. Bean and Reflection Utilities
The mapping of data between objects (Beans) is a daily task for backend engineers. Hutool 3
CopyOptions: 3.9 introduced more flexible CopyOptions, allowing developers to ignore specific properties or handle null values with greater precision during bean copying.
Reflection Performance: By caching more metadata internally, ReflectUtil saw a measurable speed boost when accessing private fields and methods. Why the 3.9 Update Mattered
While newer versions (like Hutool 5.x and 6.x) have since been released, the Hutool 3.9 UPD was a "stabilization" release. It bridged the gap between the older Java 7 paradigms and the more modern, streamlined Java 8+ coding styles. It ensured that the library remained lightweight (under 10MB) while offering features that usually require five or six separate dependencies. Summary of Key Changes Update Highlight JSON
Faster parsing and better support for nested Map structures. Setting Added support for more flexible configuration file formats. System
Better detection of JVM and OS-level environmental variables. How to Update
If you are still maintaining legacy projects using the 3.x branch, ensure your pom.xml reflects the update:
Hutool 3.9 remains a testament to the library's philosophy: "Small yet complete." It simplified the complex, standardized the scattered, and helped Java developers get back to writing business logic instead of utility methods.
They called the maintainer of Hutool—a reclusive, brilliant engineer known only as "Looly" in the commit history. Looly listened, then responded with a single line:
"3.9.1 incoming. 30 minutes."
But 30 minutes was too long. Every second, the Order Processing Tower was logging thousands of exceptions. The logs were filling disks. The monitoring alarms were screaming red.
So Old Kai did something dangerous. He wrote a runtime patch—a Java agent that intercepted calls to blankToDefault and rewrote the bytecode on the fly, restoring the old null-check logic.
"It's ugly," he said, "but it buys us time."
Lina deployed the agent. The errors stopped. Silence returned to the tower.