: It allowed developers to import only what they needed (e.g., just hutool-core ) rather than the entire library.
We recently refactored a financial dashboard application. Originally, the codebase was a mess of SimpleDateFormat threadsafety issues and homemade StringUtil classes. We introduced Hutool 3.9 (not 5.x, to avoid permission issues with the security manager).
// Convert an array of strings to integers smoothly String[] strArray = "1", "2", "3", "4" ; Integer[] intArray = Convert.toIntArray(strArray); // Safely convert to a string with a fallback default value Object standardObj = null; String result = Convert.toStr(standardObj, "Default Value"); // Convert a number to Chinese Capital Currency format (perfect for finance apps) double amount = 12345.67; String chineseMoney = Convert.digitToChinese(amount); // Output: 壹万贰仟叁佰肆拾伍元陆角柒分 Use code with caution. 2. Time and Date Simplified ( DateUtil ) Hutool 3.9
Version 3.9 focused on making the library more stable and adding neat shortcuts. Here are the best parts of this toolset:
: This module provided ultimate shortcuts for Date and Time modifications, String manipulations, and heavy Collection filtering without the heavy setup of standard JDK streams. hutool-crypto (Zero-Brainer Security) : It allowed developers to import only what they needed (e
Providing the necessary credentials or backdoors to gain deep system access to the automotive hardware. Component Recovery:
Most tool classes in Hutool 3.9 consist of stateless static methods, making them entirely thread-safe. However, be cautious with stateful objects like customized ExcelReader or specific stateful cryptographic initializers. We introduced Hutool 3
Hutool 3.9 is organized into distinct modular packages, ensuring that the library remains lightweight. Unlike monolithic frameworks, Hutool requires no external configuration files and follows a "just-add-jar" philosophy.
Complex JDK operations are wrapped into intuitive, semantic method names. Core Modules and Architectural Breakdown
Hutool 3.9 solves this pain point by adhering to three core principles:
Below is a draft of a technical paper titled