🎮 Input4j - The pure Java input library

Input4j is a cutting-edge, pure Java input library leveraging the Foreign Function & Memory API (FFM API), offering cross-platform support, high performance, flexible input handling, and future-proofing without the need for additional native artifacts, making it the best choice for Java developers.

Join the revolution in Java input handling with Input4j and experience unparalleled performance and ease of use!

🚀 Key Features

• Cross-Platform Input handling: Fully compatible with Windows, Linux, and OSX (in progress).
• Performance: Optimized for high performance with minimal overhead.
• Flexible Input Handling: Supports both polling and event-based input mechanisms.
• Simplicity: Easy to integrate and use with straightforward APIs.
• Future-Proof: Built on the latest Java technologies, ensuring long-term support and compatibility.

🆚 Advantages over traditional java input libraries

Input4j offers several advantages over traditional libraries like JInput by leveraging the new Foreign Function & Memory API (FFM API) instead of using Java Native Interface (JNI). It is a more modern and efficient JNI alternative and an easy way to interact with native input libraries, providing the following benefits:

• No Native Artifacts & No Dependencies: Direct interaction with native libraries without the need for additional native artifacts simplifies the build and deployment process.
• Performance: Based on the FFM API, this library reduces the overhead associated with native calls, resulting in significantly faster performance then Java JNI.
• Safety: Safer memory management and access patterns reduce the risk of memory leaks and buffer overflows.
• Ease of Use: A more straightforward and modern API makes it easier to write and maintain code.
• Future-Proof: Built on the latest Java technologies, ensuring long-term support and compatibility with future Java versions.

📦️ Installation

Add the following dependency to your build.gradle file to start using Input4j:

dependencies {
  implementation 'de.gurkenlabs:input4j:1.0.0'
}

💻 Quick start guide

Manually Polling and Reading Input Data

try (var inputDevices = InputDevices.init()) {
  while (!inputDevices.getAll().isEmpty()) {
    // iterate all available input devices and poll their data every second
    for (var inputDevice : inputDevices.getAll()) {
      inputDevice.poll();
      System.out.println(inputDevice.getInstanceName() + ":" + inputDevice.getComponents());
    }

    Thread.sleep(1000);
  }
}

Event-Based Input Handling

try (var devices = InputDevices.init()) {
  var device = devices.getAll().stream().findFirst().orElse(null);
  if (device == null) {
    System.out.println("No input devices found.");
    return;
  }

  device.onInputValueChanged(e -> System.out.println("Value changed: " + e.component() + " -> " + e.newValue()));
  device.onButtonPressed(XInput.X, () -> System.out.println("X button pressed"));
  device.onAxisChanged(Axis.AXIS_X, value -> System.out.println("X axis: " + value));

  // simulate external polling loop
  while (true) {
    device.poll();
    Thread.sleep(1000);
  }
}

🔌 Technical Details

Platform-Specific Input APIs

• Windows: DirectInput ✅

  • Full implementation using dinput.h
  • Supports legacy and modern input devices

• Windows: XInput ✅

  • Modern gamepad support via xinput.h
  • Xbox controller compatibility

• Linux: evdev ✅

  • Event interface via /dev/input

• macOS: IOKit ✅

  • HID device provisioning via IOHIDManager

System Requirements

• Java Runtime: 22+