OrionBLE

A Java library that enables communication with Bluetooth Low Energy devices.

OrionBLE is a custom implementation of Bluetooth Low Energy (BLE) APIs that allows developers to communicate with nearby devices easily in a standard Java environment.

Why is this necessary?

Well, the only specification for Bluetooth Java APIs is the Java Bluetooth API (JSR-82), however it is effectively abandoned and has been stuck on Maintenance Draft Review 4 since 2010. Additionally, it only supported Java ME, which is also effectively abandoned and left standard desktop applications without a way to communicate with BLE devices.

Are there any alternatives?

There seem to be two JSR-82 implementations for Java SE, BlueCove and AvetanaBluetooth. Both are abandoned and have been unmaintained for years! Intel's IoT devkit, TinyB, has also been abandoned and archived since 2023.

Thus, OrionBLE was born, to provide a modern, easy-to-use, and well-documented Java library for BLE communication.

How does it work?

OrionBLE is not an implementation of JSR-82, but rather a custom implementation. As of now, it only supports the Windows platform.

OrionBLE is broken into two separate parts: the OrionBLE Java library and the OrionBLEServer .NET application. The server backend exposes a REST API that the Java library communicates with to interact with BLE devices. The server is automatically included, so no additional setup is required.

How do I use it?

Update your project's buildscript to include my Maven repository:

repositories {
	maven {
		url "https://maven.anonymoushacker1279.tech/releases"
	}
	// Alternatively, snapshot versions may be available under:
	maven {
		url "https://maven.anonymoushacker1279.tech/snapshots"
	}
}

Then, add the following dependency to your project:

dependencies {
	implementation "tech.anonymoushacker1279:OrionBLE:<VERSION>"
}

The latest version can be found on the releases page. There are three usable artifacts: the regular one, slim, and all. The regular one contains the library and its backend server, the slim one contains only the library, and the all one contains the library, server, and all dependencies (such as gson).

The library is very simple to use. Here is an example of how to scan for BLE devices:

import tech.anonymoushacker1279.orionble.*;

public class ScanForDevices {

	public static void main(String[] args) {
		// Create a new OrionBLE instance, with the server running on localhost and port 5249
		OrionBLE orion = new OrionBLE("http://localhost", 5249);
		// Wait for a server connection. Creating an instance above will automatically try to launch the backend server.
		// You don't technically have to wait, but it's recommended so you don't run into connection issues.
		// If you're sure a server is already running, feel free to skip this step.
		orion.waitForConnection(5);

		System.out.println("Discovering devices...");
		// Discover devices and print them to the console
		for (BLEDevice device : orion.discoverDevices()) {
			System.out.println(device);
		}
	}
}

You'll get an output similar to this:

Discovering devices...
Some Device (ADDRESS) - Not Paired
Another Device (ADDRESS) - Paired
Yet Another Device (ADDRESS) - Paired

There are more examples available in the repository under the test sources.

BLE Feature Support

Support is added as needed. If you need a feature that is not currently supported, feel free to open an issue or contribute to the project.

GATT Characteristics

Property	Supported
Broadcast	No
Read	Yes
Write with No Response	Yes
Write	No
Notify	Yes
Indicate	No
Authenticated Signed Write	No

License

OrionBLE is MIT licensed. See the LICENSE file for more information.