Unlock Java Productivity with Hutool: Essential Tools and Real‑World Examples

What Is Hutool?

Hutool (pronounced “hu‑tu”) is a Java utility library that aims to make coding simpler and more pleasant by providing concise wrappers for common JDK functionality.

Key Modules

hutool-aop – JDK dynamic‑proxy AOP support without an IoC container.

hutool-bloomFilter – Bloom filter implementation with several hash algorithms.

hutool-cache – Caching utilities.

hutool-core – Core utilities such as Bean handling, date manipulation, and general helpers.

hutool-cron – Cron‑style scheduling without external frameworks.

hutool-crypto – Encryption and decryption utilities.

hutool-db – JDBC wrapper based on ActiveRecord concepts.

hutool-dfa – Multi‑keyword search using DFA.

hutool-extra – Extensions for third‑party integrations (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 – Enhanced configuration file handling.

hutool-system – System and JVM information utilities.

hutool-json – JSON processing.

hutool-captcha – Image captcha generation.

Simple Usage Examples

Using SecureUtil for MD5 hashing during login:

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

Escaping user input with HtmlUtil.encode to prevent XSS:

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

Additional HtmlUtil methods include restoreEscaped, cleanHtmlTag, removeHtmlTag, unwrapHtmlTag, removeHtmlAttr, removeAllHtmlAttr, and filter for XSS protection.

Cron Scheduling with CronUtil

CronUtil enables lightweight scheduling without external dependencies. Define tasks in a cron.setting file and start them with CronUtil.start():

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){
    // other initialization
    CronUtil.start();
    log.info("定时任务启动成功！");
}

For full documentation see the Hutool docs at http://hutool.mydoc.io/?t=255673. The library’s official site is http://www.hutool.cn/.