An Overview of the Hutool Java Utility Library and Its Common Tools

Hutool (pronounced “hu‑tu”) is a comprehensive Java utility library that aims to simplify code by providing a wide range of reusable components.

Features

The library wraps many JDK functionalities such as file I/O, streams, encryption, encoding, regular expressions, threading, XML, and offers dedicated modules including:

hutool-aop – dynamic proxy AOP support without IoC.

hutool-bloomFilter – Bloom filter implementations with various hash algorithms.

hutool-cache – caching utilities.

hutool-core – core utilities like bean handling, date operations, and general helpers.

hutool-cron – lightweight scheduling based on Crontab expressions.

hutool-crypto – encryption and decryption utilities.

hutool-db – JDBC wrapper with ActiveRecord style data access.

hutool-dfa – multi‑keyword search using DFA.

hutool-extra – wrappers for third‑party tools (template engines, mail, etc.).

hutool-http – HTTP client based on HttpUrlConnection.

hutool-log – automatic detection of logging implementations.

hutool-script – script execution (e.g., JavaScript).

hutool-setting – advanced configuration file handling.

hutool-system – system and JVM information utilities.

hutool-json – JSON processing.

hutool-captcha – image captcha generation.

Simple Usage Examples

SecureUtil – encryption/decryption:

user = userService.userLoginByName(loginName, SecureUtil.md5(loginPwd));

HtmlUtil – HTML escaping to prevent XSS and SQL injection:

comment.setCommentAuthor(HtmlUtil.encode(comment.getCommentAuthor()));

HtmlUtil also provides methods such as restoreEscaped, cleanHtmlTag, removeHtmlTag, unwrapHtmlTag, removeHtmlAttr, removeAllHtmlAttr, and filter for various HTML sanitization tasks.

CronUtil – scheduling without external frameworks

Define tasks in a cron.setting file and start them with CronUtil.start() . Example configuration:

cc.ryanc.halo.web.controller.admin.BackupController.backupResources = 0 0 1 * * ?
cc.ryanc.halo.web.controller.admin.BackupController.backupDatabase = 0 0 1 * * ?
cc.ryanc.halo.web.controller.admin.BackupController.backupPosts = 0 0 1 * * ?
@Override
public void onApplicationEvent(ContextRefreshedEvent event){
this.loadActiveTheme();
this.loadOptions();
this.loadFiles();
this.loadThemes();
// start scheduled tasks
CronUtil.start();
log.info("Scheduled tasks started!");
}

For full documentation see http://hutool.mydoc.io/?t=255673. The author recommends trying other modules as the library is considered one of the most convenient Java toolkits.

Official website: http://www.hutool.cn/