HAP-Java is a Java implementation of the Homekit Accessory Protocol.
Using this library, you can create your own Homekit Accessory or Homekit Accessory Bridge.
Because the MFi Specification is closed to individual developers, and this implementation was made without access to that specification, it may not be complete. iOS devices do recognize and are able to interact with accessories exposed via this library however.
This library would not have been possible without Tian Zhang who did a lot of the hard work of figuring out how the protocol works in his NodeJS implementation.
Include HAP-Java in your project using maven:
<dependency>
<groupId>com.beowulfe.hap</groupId>
<artifactId>hap</artifactId>
<version>1.1.3</version>
</dependency>