Hutool 3.9

Hutool 3.9 adheres to the "Principle of Least Surprise." It utilizes static utility classes (XxxUtil) to minimize object instantiation overhead. In version 3.9, significant effort was placed on null-safety and exception handling, ensuring that common runtime exceptions (e.g., NullPointerException) are gracefully managed within utility logic rather than propagating to the application layer.

Search & replace imports from old package (com.xiaoleilu.) to cn.hutool..

Rebuild project and fix compile errors — pay attention to:

Run tests focusing on:

Replace removed deprecated methods with recommended alternatives (see API javadocs).

The v3.9 release focused on stabilizing the core feature set. Key components analyzed include: Hutool 3.9

Released as a significant milestone, Hutool 3.9 is not just a patch; it introduced several key features that solidified its reputation. If you are evaluating an upgrade from 3.8 or earlier, these are the highlights: Hutool 3

The 3.9 release structure is defined by the cn.hutool.core root package, segmented into: Search & replace imports from old package (com

It is 2025 (or later), and Java 17/21 are mainstream. Why on earth would anyone write an article about Hutool 3.9? Stability.