Getting Started

dmx-fun is a functional programming library for Java that provides essential tools and utilities for writing functional code in a type-safe and composable way.

Installation

Maven

Add the following dependency to your pom.xml:

<dependency>
  <groupId>codes.domix</groupId>
  <artifactId>fun</artifactId>
  <version>0.0.7</version>
</dependency>

Gradle

Add the following to your build.gradle:

implementation 'codes.domix:fun:0.0.7'

Requirements

Java 24 or higher
No additional dependencies required

Core Concepts

Option

The Option type represents an optional value. It's a type-safe alternative to null.

import codes.domix.fun.Option;

 class OptionExample {
    void main() {
        // Create an Option
        Option<String> some = Option.some("Hello");
        Option<String> none = Option.none();

        // Map over Option
        Option<Integer> length = some.map(String::length); // Some(5)

        // Provide default value
        String value = none.getOrElse("Default"); // "Default"

        // Chain operations
        Option<String> result = some
            .filter(s -> s.length() > 3)
            .map(String::toUpperCase); // Some("HELLO")
    }
}

Try

The Try type represents a computation that may either result in an exception or return a value.

import codes.domix.fun.Try;

class TryExample {
    void main() {
        // Wrap risky operations
        Try<Integer> result = Try.of(() -> Integer.parseInt("123"));

        // Handle success and failure
        String message = result
            .map(i -> "Success: " + i)
            .recover(throwable -> "Failure: " + throwable.getMessage())
            .get();

        // Chain operations
        Try<Integer> computed = Try.of(() -> "42")
            .map(Integer::parseInt)
            .map(i -> i * 2); // Success(84)
    }
}

Result

The Result type represents a value of one of two possible types (a disjoint union).

import codes.domix.fun.Result;

class ResultExample {
    void main() {
        Result<Integer, String> result = Result.ok(123);
        result.map(i -> i + 1);        // Result.ok(124)
        result.isOk();                 // true
        result.get();                  // 124

        Result<Integer, String> failure = Result.err("error");
        failure.map(i -> i + 1);        // Result.err("error")
        failure.isError();              // true
        failure.getError();             // "error"
    }
}