Chronos

Chronos is a lightweight, high-performance Java scheduling library designed for modern applications.

Standard Java scheduling solutions often force a choice between simplicity and capability. ScheduledExecutorService is simple but lacks essential features like Cron support and persistence hooks. Quartz is powerful but heavy, complex, and brings in numerous dependencies. Chronos fills that gap in the middle.

Features

• Zero Dependencies: The library depends only on the Java 21 standard library.
• Flexible Scheduling: Support for standard patterns including Cron (timezone-aware), Fixed Rate, Fixed Delay, and One-Shot execution.
• Resilience: Built-in support for execution policies, including exponential backoff retries and deadline handling.
• Jitter Support: Prevents thundering herd problems by adding configurable randomness (Uniform, Gaussian) to execution schedules.
• Observability: First-class support for TaskListener and comprehensive metrics snapshots to monitor scheduler health and task performance.
• High Performance: Zero-allocation hot paths for recurring tasks and efficient, lock-free state management where possible.

Installation

This library is available via JitPack.

Gradle (Groovy)

repositories {
    mavenCentral()
    maven { url 'https://jitpack.io' }
}

dependencies {
    implementation 'com.github.frosxt:Chronos:v1.0.0'
}

Gradle (Kotlin)

repositories {
    mavenCentral()
    maven { url = uri("https://jitpack.io") }
}

dependencies {
    implementation("com.github.frosxt:Chronos:v1.0.0")
}

Maven

<repositories>
    <repository>
        <id>jitpack.io</id>
        <url>https://jitpack.io</url>
    </repository>
</repositories>

<dependency>
    <groupId>com.github.frosxt</groupId>
    <artifactId>Chronos</artifactId>
    <version>v1.0.0</version>
</dependency>

Requirements

• Java 21 or newer
• Gradle or Maven

Documentation

Documentation is available on the Wiki.

License

MIT License. See LICENSE.