Hutool 39 May 2026

Props props = new Props("config/db.properties");
String url = props.getStr("jdbc.url");

If you are on 3.9.x, consider upgrading:

| 3.9.x | 5.x+ | |-------|------| | Convert.toStr() | Convert.toStr() (same) | | SecureUtil.aes() | SecureUtil.aes() (improved) | | ImgUtil.pressText() | More parameters | | No CollUtil.getFirst() | CollUtil.getFirst() |

Migration guide: Most APIs are backward compatible, but check deprecation warnings.

Yes, if:

No, if:

For new projects, consider Hutool 5.x (actively maintained). But for a solid, battle-tested utility library that just works, 3.9 remains a hidden gem.

implementation 'cn.hutool:hutool-all:5.8.26'

Note: Hutool is modular. You can import hutool-core or hutool-http individually if you don't want the whole library. hutool 39

Hutool is a small, yet powerful Java utility library that encapsulates common methods in a friendly, fluent API. Version 3.9.x focuses on:

Copying streams, reading files to strings, and closing resources is tedious.

// Read file to string (auto handles encoding)
String content = IoUtil.readUtf8(new FileInputStream("test.txt"));
// Copy stream
IoUtil.copy(inputStream, outputStream); Props props = new Props("config/db
// Close quietly (no try-catch needed)
IoUtil.close(inputStream);