jct

Lightweight Java implementation of an operation cancellation mechanism, similar to C#'s CancellationToken. Designed to be minimal, composable, and runtime-agnostic — works well with standard Java concurrency tools and third-party frameworks.

Getting Started

To use this library, you will need:

• Java 11 or higher
• Maven or Gradle

Features

• Immutable, thread-safe CancelToken abstraction
• Simple and lightweight cancellation source (CancelSource)
• Composable tokens (linked or combined)
• Integration with CompletableFuture and any asynchronous workflows
• Memory-friendly: CancelSource supports reuse via reset()

Installing

Gradle dependency

dependencies {
    implementation group: 'com.github.romanqed', name: 'jct', version: '1.2.1'
}

Maven dependency

<dependencies>
    <dependency>
        <groupId>com.github.romanqed</groupId>
        <artifactId>jct</artifactId>
        <version>1.2.1</version>
    </dependency>
</dependencies>

Usage Examples

Creating a cancelable operation

CancelSource source = Cancellation.source();
CancelToken token = source.token();

CompletableFuture<Void> future = token.onCancelled().thenRun(() -> {
    System.out.println("Cancelled!");
});

// Later:
source.cancel();

Combining tokens

CancelToken token1 = Cancellation.source().token();
CancelToken token2 = Cancellation.source().token();

CancelToken combined = Cancellation.combinedToken(token1, token2);

combined.onCancelled().thenRun(() -> {
    System.out.println("Any of the tokens was cancelled");
});

Reusing a source

CancelSource source = Cancellation.source();

// Use source.token() in one task
runCancellableTask(source.token());

// Cancel and reset
source.cancel();
source.reset();

// Reuse for another task
runCancellableTask(source.token());

Empty token (never cancels)

CancelToken empty = Cancellation.emptyToken();

empty.onCancelled().thenRun(() -> {
    // Will never be invoked
});

Built With

• Gradle - Dependency management

Authors

• RomanQed - Main work

See also the list of contributors who participated in this project.

License

This project is licensed under the Apache License 2.0 - see the LICENSE file for details